Monday, September 13, 2010

Environment 360

17 Feb 2011: Report

Climate’s Strong Fingerprint
In Global Cholera Outbreaks

For decades, deadly outbreaks of cholera were attributed to the spread of disease through poor sanitation. But recent research demonstrates how closely cholera is tied to environmental and hydrological factors and to weather patterns — all of which may lead to more frequent cholera outbreaks as the world warms.

by sonia shah

Sonia Shah is an author and science journalist whose writing has appeared in The Nation, New Scientist, The Washington Post and elsewhere. Her third book, The Fever: How Malaria Ruled Humankind for 500,000 Years, will be published in 2010. In previous articles for Yale Environment 360, she has written about the spread of new pathogens and the threat of pharmaceuticals being released into the environment.

Since cholera first erupted from India’s Ganges delta in 1817, the bacterial pathogen has swept across the globe in no fewer than seven worldwide pandemics, afflicting hundreds of millions of people and killing more than 70 percent of its victims within hours if left untreated.⁠ The seventh pandemic — the longest one yet — began in Celebes, Indonesia in 1961, and has spread to more than 50 countries and 7 million people.⁠ That pandemic continues to this day, staking its latest beachhead in earthquake-ravaged Haiti, where a cholera epidemic occurred last year after a reported absence of some 100 years.

Historically and in the modern popular imagination, cholera has been considered a disease of filth carried in sewage. And yet, over the past decade, research on cholera’s natural habitat and links to the climate have revealed a revolutionary new understanding of the disease as one shaped just as much by environment, hydrology, and weather patterns as by poor sanitation. And as temperatures continue to rise this century, cholera outbreaks may become increasingly common, with the bacteria growing more rapidly in warmer waters.

The University of Maryland cholera expert Rita Colwell, a former director of the National Science Foundation, pioneered the study of Vibrio cholerae, the bacteria that causes cholera, in the environment. She and

Attributing cholera to environmental influences undermines efforts to prevent the disease, some scientists worry.

others have discovered the bacteria in water bodies untouched by human waste, its abundance and distribution fluctuating not with levels of contamination, but with sea surface temperature, ocean currents, and weather changes. After several centuries during which cholera’s spread has been attributed solely to human activity, it has been paradigm-shifting research. “Thirty years ago, we were ridiculed to even say that the bacterium existed in the environment,” Colwell says. “But now it is in textbooks. The evidence is so overwhelming, it is understood.”

While cholera epidemics are caused by multiple factors, of which environmental influences are just one, Colwell and other experts are closely monitoring the potential impact of global warming on the diarrheal disease. “Although there is no clear understanding of the exact nature of the relationship between cholera and climate,” says Tufts University cholera expert Shafiqul Islam, “if climate change leads to more extremes, it will have an impact on cholera.” In fact, it may already have. Over the past 30 years, El Nino events in the Bay of Bengal — characterized, in part, by warmer sea surface temperatures — have increased, paralleling a rise in cholera cases in Bangladesh. The World Health Organization calls it “one of the first pieces of evidence that warming trends are affecting human infectious diseases.”

The growing understanding of the role that climate plays in cholera outbreaks has sparked disagreement between environmental scientists, such as Colwell, and the medical community. While many cholera researchers concur that these environment influences play an important role in the incidence of cholera, especially in places such as Bangladesh and India, most hail from medical fields, which continue to emphasize the role of human activity in the spread of the disease. Scientists such as Matthew Waldor, an infectious disease expert from Harvard University, worry that characterizing cholera outbreaks as a result of environmental influences undermines efforts to prevent the disease using vaccines and other methods.


Phytoplankton blooms, like this one in the Bay of Bengal, are one way that scientists can forecast cholera outbreaks.

“There is an inevitability to the environmentalist arguments about cholera,” he says. “If cholera travels by the environment... then it is not preventable.” Whereas linking cholera outbreaks to human activity, he says, reinforces the indisputable — and uncontested — truth that preventing cholera requires changing human activity.

And yet, new research on cholera’s links to the environment may help minimize cholera’s damage in other ways. The macro-environmental factors that drive cholera can be tracked using remote sensing data and other forecasting methods, opening up the possibility of an early warning system for cholera. Islam is among several scientists developing methods to use remote sensing data to track the coastal plankton blooms that presage cholera outbreaks. Satellite data on chlorophyll concentrations, a discernible proxy for zooplankton levels, can successfully predict cholera incidence, too. NOAA recently funded the development of a system to predict levels of Vibrio cholerae in the Chesapeake Bay using data on the bay’s changing salinity and surface temperature.

In fact, cholera surveillance teams from the World Health Organization (WHO) have already used El Nino forecasting to help prepare communities for potential cholera outbreaks, including one in Mozambique in 1997, predicted by the WHO based on forecasts of El Nino-related drought in southeast Africa.

What is clear is that populations of Vibrio cholerae in coastal waters, estuaries, and bays rise and fall in association with a range of environmental factors. In Peru, levels of cholera vibrio bacteria have been linked to the temperature of local rivers; in Italy, to the surface

In Bangladesh, cholera risk increases two to four times following a 5-degree C spike in the water temperature.

temperatures of estuaries along the Adriatic coast. In Mexico, the abundance of cholera vibrios in lagoon oysters rise as seas warm. In the Chesapeake Bay, Vibrio cholerae levels increase during the summer, as water temperatures spike. In Bangladesh, cholera risk increases by two to four times in the six weeks following a 5-degree C (9-degree F) spike in the water temperature⁠. Likewise, in Ghana, an analysis of 20 years of data revealed a correlation between cholera incidence and rainfall and land surface temperatures. In Djibouti, Somalia, Kenya, Mozambique, and Tanzania, cholera epidemics have been correlated with flooding as well as sea surface temperatures.

Global climate drivers such as the El Nino Southern Oscillation and the Indian Ocean Dipole appear to be similarly linked to the incidence of cholera. The El Nino Southern Oscillation — in which warm waters build up in the central and eastern Pacific and the Indian Ocean — creates extreme weather conditions, including floods. El Nino cycles have occurred for centuries, but some scientists believe they will become more frequent and will intensify as the world warms.

Scientists from the University of Michigan and the University of Barcelona analyzed 70 years of data on cholera prevalence in Bangladesh, finding an association between cholera incidence and increasingly intense El Nino events that began in 1980. Statistical modeling by scientists at the University of Santiago de Compostela in Spain found a correlation between the pattern of pathogenic vibrio infections in Peru with El Nino events, a relationship experts suspect may be responsible for a massive cholera outbreak in Peru that occurred during El Nino events in 1991.

Predicted changes to the climate thanks to global warming may intensify these effects. A 2003 WHO study warned that predicted warming of African lakes, such as Lake Tanganyika, may increase the risk of cholera transmission among local people, and that countries such as Tanzania, Kenya, Guinea-Bissau, Chad, Somalia, Peru, Nicaragua, and Honduras —

‘We could again see epidemics of cholera in the U.S. and Europe that we haven’t seen in 100 years,’ says one expert.

which suffered major cholera outbreaks after heavy rains in 1997 — may face more cholera epidemics as the climate changes.

Climate change-driven storms, flooding, and heavy rainfall may lead to the spread of cholera in other ways, too. “Extreme weather events can lead to a breakdown in sanitation, sewage treatment plants, water treatment systems,” says Colwell. “And indeed, because the bacteria are part of the natural environment, we could again begin to see epidemics of cholera in the U.S. and in Europe that we haven’t seen in almost a hundred years.”

Climatic and hydrological changes lead to cholera outbreaks by creating the ecological conditions in which cholera vibrios thrive. While Vibrio cholerae has been found free-living in aquatic environments, and clinging to fish, insects, and waterfowl, they are most often found in association with widely dispersed zooplankton called copepods. The vibrios attach to the carapace and guts of copepods, where they replicate and ultimately cover the surface of the female copepod’s egg sack.⁠

Warm, nutrient-rich water helps promote cholera vibrio growth because it leads to phytoplankton blooms, and within a week or two, corresponding spikes in copepods and other zooplankton that feed on phytoplankton.⁠ Droughts can promote the growth of cholera vibrios by increasing salinity in local waters, which helps Vibrio cholerae attach to copepods, while floods help distribute the bacteria more widely. Climatic and environmental changes may alter the local species composition of copepods, some of which may play a bigger role in hosting cholera vibrio than others, says Colwell’s collaborator, the microbiologist Anwar Huq.

The scientific debate over the relative role of the environment in shaping cholera recently flared into political controversy in the wake of the devastating outbreak in Haiti. Enraged rioters in Haiti blamed the United Nations’ Nepalese peacekeepers and leaky sewage pipes at their camps for contaminating the country with cholera.

Experts such as Harvard’s Waldor agree. “This strain [in Haiti] came from very, very far away,” Waldor says. He was part of a team that found genetic similarities between the strain of cholera in Haiti and ones in South Asia. “If you have the same genomic sequence in two different places like continents, the most likely explanation is that human beings brought one strain to the

‘Cholera cannot be defeated by medicine alone — we need a new approach,’ one scientist says.

next,” Waldor says. “That goes back hundreds of years in the history of cholera. Ships from one part of Asia brought it elsewhere... It was spread by humans.”

Colwell doesn’t think so. “To ascribe outbreaks solely to introductions externally is not what modern ecological data tell us,” she says. “The data we’re gathering for the last 40 years show that these bacteria are part of a natural aquatic environment, and the molecular genetic evidence now accumulating is pretty convincing that the outbreaks are local. You can have it introduced, but the big outbreaks are generally local.”

In Haiti, Colwell says, the earthquake washed silt and limestone into the river system, creating the nutrient-rich, alkaline conditions that cholera vibrios thrive in, just as an extremely warm summer set in. Rising concentrations of cholera bacteria coincided with an explosion of malnourished refugees with little access to treated water. It’s a series of events that has triggered cholera outbreaks before, she says.

Colwell points out that the genetic analysis of the strain in Haiti is complicated by the fact that cholera vibrio are genetic rogues, with many mobile elements in their genomes, and the Haiti strain, while genetically similar to a South Asian strain, is also similar to one found in East Africa.⁠ According to Colwell, more research will be required to unravel the true origins of Haiti’s cholera. The trouble is that the very idea of environmentally driven outbreaks “is resisted by the medical community,” she says. “But this is new data. And it is typical, when you produce a new hypothesis, it takes years for acceptance.”


As Pharmaceutical Use Soars,
Drugs Taint Water and Wildlife

As Pharmaceutical Use Soars, Drugs Taint Water and Wildlife

With nearly $800 billion in drugs sold worldwide, pharmaceuticals are increasingly being released into the environment. The “green pharmacy” movement seeks to reduce the ecological impact of these drugs, which have caused mass bird die-offs and spawned antibiotic-resistant pathogens.

“Physicians are not trained in ecology,” says Colwell, who has taught in medical schools. And yet, “in the twenty-first century of emerging disease, the source is the environment, and animals in the environment... Epidemiology really needs to take into account the ecology of microbial systems.”

That’s not to say that the old truths don’t still hold true. “This is a disease of poverty,” says Islam. The solution, he says, is simple: Clean drinking water, good sanitation, and vaccines prevent the disease, and prompt rehydration treatment and antibiotics cure it.

But with the environment changing, the disease on the move, and poverty still entrenched in many parts of the world, “cholera cannot be defeated by medicine alone,” he adds. “We need a new approach.”


Good Article.

I agree with the many points raised.

Here is more to add to the issue.

Climate Change Increases Cholera Cases In Africa, Study Suggests

ScienceDaily (Apr. 27, 2009) — A study led by researchers from the Madrid Carlos III Institute of Health associates the increase of cholera cases in Zambia with climatic factors. For the first time, the results confirm that the increase in environmental temperature six weeks before the rain season increases the number of people affected by this sickness by 4.9%.

"This is the first time that it has become evident in the sub-Saharan region that the increase in environmental temperature is related to the increase in cholera cases," explains Miguel Ángel Luque, one of the study's authors and researcher from the Madrid Carlos III Institute of Health (ISCIII), to SINC. Previous studies in Bangladesh already associated the cases with an increase in ocean surface temperature.

Dr.A.Jagadeesh Nellore (AP), India

Posted by Dr.A.Jagadeesh on 17 Feb 2011

05 Mar 2009: Analysis

Surviving Two Billion Cars:
China Must Lead the Way

The number of vehicles worldwide is expected to reach two billion in the next two decades. Surprisingly, China – where the demand for cars has been skyrocketing – just may offer the best hope of creating a new, greener transportation model.

by deborah gordon and daniel sperling

Deborah Gordon is a transportation policy analyst who has worked with the National Commission on Energy Policy, the California Energy Commission, the Hewlett Foundation, and with the Chinese government to develop policies for its burgeoning auto fleet. She has also served as the director of the transportation and energy programs at the Union of Concerned Scientists. Daniel Sperling is professor of engineering and environmental science & policy at the University of California, Davis, and founding director of UC-Davis’s Institute of Transportation Studies. He also serves on the California Air Resources Board, and has authored 10 books and over 200 technical papers and reports on transportation and energy. They are the authors of the recently published book, Two Billion Cars: Driving Toward Sustainability.

From Shanghai to Sao Paulo, from Seoul to Tehran, conventional cars powered by conventional fuels are proliferating, intensifying economic, environmental, and energy stresses in the world’s fastest-growing metropolitan areas. Booming cities such as Bangkok and Moscow now have so many cars that their central thoroughfares look more like parking lots than streets. Unless we transform vehicles, fuels, and our concept of mobility, we will choke — literally and figuratively.

The globe now has more than 1 billion vehicles and is expected to hit the 2 billion mark within 20 years. And while the international economic crisis may have slowed things down momentarily, the desire for personal vehicles is powerful and the demand will not soon let up.

America pioneered the motorization of human society and leads the world in auto ownership today, with more than one auto for every licensed driver. But with vehicle growth rates over the past decade slowing to around 1 percent to 2 percent a year in the U.S., Western Europe, and Japan, most vehicle growth is now in emerging nations. As the world gets richer, private car use will zoom ahead, especially among the 2.4 billion citizens of China and India. Beijing alone now adds nearly 1,500 cars to its roads every day.

Automakers are increasingly focusing their efforts on these emerging markets, with their phenomenal growth potential. A mass migration to

In January, for the first time ever, more cars were sold in China than in the United States.

urban areas has been driving the demand for autos. Over the past decade, China has tripled its vehicle fleet to 45 million while India’s has doubled to 15 million. And these figures do not include tens of millions of motorcycles and small, rural vehicles in these nations. In January 2009, for the first time ever, more cars were reportedly sold in China than in the U.S.

The question is, by 2020, how will the world’s growing mobility demands be met? If we remain wedded to conventional vehicles powered by conventional fuels, then we will be in a lot of trouble. Instead, we need long-overdue transportation innovations that will lead to cleaner, more efficient, safer vehicles running on greener fuels, together with an overhaul of public transportation systems and land-use development. Nowhere is this more urgent than in China.

Whichever countries bring these transportation innovations to the marketplace stand to gain economically and, politically, as champions of the public interest. Nations such as Japan, France, and the U.K and U.S. states such as California are taking the lead in terms of policy innovation, crafting laws that creatively deal with air quality, climate, and energy solutions. California enacted the first vehicle greenhouse gas emission standards that take into account the entire fuel cycle, from the wellhead to the wheel. France has bundled incentives and disincentives together to simultaneously reward, or penalize, consumers who buy lower, or higher, carbon-emitting cars. But it is China — with its limited oil resources, rapid development, and polluted cities — that may emerge as a leader.

This is because China is a hotbed of innovation, well positioned to respond to internal demands and international initiatives. Novel technologies are already sweeping China. Electric two-wheelers are the most successful

University of California, Berkeley

The popularity of electric two-wheelers in China may accelerate the growth of the electric-vehicle industry.

mass-marketed battery-powered electric vehicles in the world, with sales exceeding 15 million in China in 2007. They have immediate air-quality benefits, set the stage for a shift toward cleaner three- and four-wheel electric vehicles, and accelerate the development of the low-cost battery sector. Chinese automakers are also innovating with new ferrous batteries that could be much cheaper than lithium-ion or nickel-metal hydride batteries and could be recharged in 10 minutes. This breakthrough would enable large-scale introduction of electric vehicles in China, ahead of Western Europe and the United States.

Low-carbon vehicle fuels from coal are another innovation China is working on, aided by international support for carbon capture and sequestration technologies. And bus rapid transit (BRT), where dedicated bus lanes carry almost as many passengers as a metro rail system at a fraction of the cost, are gaining widespread acceptance in Beijing, Shanghai and, other cities.

China’s government is also playing an increasingly supportive role in fostering innovation. It has imposed fuel economy standards on vehicles that are more aggressive than those in America and has adopted tough tailpipe standards that are closing the gap with the United States. Chinese leaders are adopting fiscal measures to shift taxes to favor more fuel-efficient cars.

These ideas are not entirely new. But what China can do, with its massive size and economy, is foster these ideas until they are fully developed and then launch them abroad.

It will take more than technological innovation, however, to transform transportation in China and the developing world. Sprawling land use and vehicle use must be managed and restrained. This will take government intervention, both through regulations and fiscal policies such as gas taxes and emissions fees.

In China and elsewhere, cities are following different paths when dealing with the problems associated with a growing number of vehicles. In the name of congestion, safety, and even public image, certain cities —


Traffic gridlock in Bangkok

including Guangzhou, Hangzhou, and Shanghai — severely restrict or ban motorcycles, small rural vehicles, small cars, and even bicycles. Shanghai caps the number of new private car registrations annually, auctions auto registrations, limits parking, and makes it difficult to obtain a driver’s license. The city is considering a plan to charge cars for entering the central business district, as now exists in London. Shanghai’s more restrictive policies have led to a slower rate of car growth. With about the same population and wealth as Beijing, Shanghai residents own only one car for every six in Beijing.

Chinese mobility isn’t yet fixated on cars, except maybe in Beijing, where pro-car policies mean that new highways are built as quickly as old ones fill up. An enlightened car policy is key. Stronger metropolitan institutions such as regional planning commissions are needed to protect the environment, manage land development, and provide public transportation. China’s increasingly entrepreneurial culture must be allowed to leapfrog to new technologies that thrive at home and could be exported abroad, such as lightweight, plug-in hybrid vehicles, new electric-car infrastructure advances, and real-time, wireless travel information devices.

Will China actually play a leadership role in transforming vehicles, fuels, mobility, and land use? We think so, for a variety of reasons. For one, some in China are beginning to recognize the Faustian bargain of automotive industry success. They gain jobs, but suffer a raft of environmental, social, and even economic problems. China’s strong national and local governments could pave the way for precedent-setting fiscal and regulatory policies, such as emission-indexed vehicle user fees. The Chinese government is capable of strong and effective intervention, as demonstrated with its one-child policy. Imagine a similar policy applying to car ownership.

And then there are the Chinese people themselves. Despite sometimes harsh limits on personal freedom, they’re becoming more outspoken in demanding a cleaner environment. All of this could add up to positive results as consumers and governments pressure automakers, oil companies, and developers that seek to thrive in one of the world’s fastest-growing nations.

Yet China’s fate rests not only on well-orchestrated approaches within the country, but also on international policies aimed at China. As China speeds ahead, the rest of the world must help steer. Financial incentives, technical assistance, and political pressure from the United States and other nations

Following the U.S. down the wrong path toward fossil fuel-dependent motorization could be catastrophic.

are needed. For example, public-private investment funds targeted at clean transport technologies, multilateral government support to increase financing of sustainable transportation projects, and help developing zero-emission-vehicle policies could all spur China to pursue a more sustainable course. The most car-centric nations owe it to themselves to be involved as more than mere observers. It’s in their self-interest to enthusiastically and generously help China pursue a more benign transportation and energy path. When it comes to transportation, China’s missteps could be devastating, while its revolutionary innovations could be lifesaving for us all.

This isn’t charity. While China would benefit from aid and partnerships, so would the rest of the world. There are other awakening giants in our midst. Vehicle ownership in India, Brazil, Russia, and many other countries is rising rapidly. China might offer them a global model to follow.

Instead of overlooking or decrying the growing demand for cars in China, India, and elsewhere, the U.S. needs to encourage innovative solutions. As the global economy rebounds, China is poised to regain its phenomenal growth in affluence and mobility. Following the U.S. down the wrong path toward fossil fuel-dependent motorization could be catastrophic. Charting another course could be immensely beneficial.

We all win if tomorrow’s vehicles, fuels, and land use are transformed according to a new vision, one that accommodates the desire for personal mobility but with a reduced environmental footprint. It’s a vision that accommodates two billion vehicles, but rejects a transportation monoculture that isn’t going to take us where we need to go.


No doubt car usage is at an exponential rise in developing countries also. But in China usage of bicycles is high. There are separate lanes for bicycle riders. I was astonished at the number of bicycle users in Beijing itself. As I often quote there may be a time, with proliferation of cars” WHERE THERE IS A WHEEL, THERE IS NO WAY".

Dr.A.Jagadeesh Nellore (AP), India

Posted by Dr.A.Jagadeesh on 06 Feb 2011

02 Dec 2010: Report

Green Roofs are Starting
To Sprout in American Cities

Long a proven technology in Europe, green roofs are becoming increasingly common in U.S. cities, with major initiatives in Chicago, Portland, and Washington, D.C. While initially more expensive than standard coverings, green roofs offer some major environmental — and economic — benefits.

by bruce stutz

The low scrubland of densely packed succulents is in full fall color, a carpet of green fading brilliantly to red and gold. This 2.5-acre oasis, located among a barrens of blacktop roofs that stretches east to Broadway and west to the Hudson River, would be an impressive sight even if it wasn’t sitting atop the U.S. Postal Service’s 1933 landmark Morgan Processing and Distribution facility in midtown Manhattan.

The biggest green roof in New York City and one of the largest in the country, the Morgan facility’s verdant covering was completed in December 2008 and has thrived since. As the inscription above the landmark James Farley Post Office might have it, the roof has been affected by “neither snow nor rain nor heat nor gloom of night,” and has flourished through freezes and thaws, through summer rooftop temperatures that reach 150 degrees, and through weeks of drought and torrential summer storms, despite never being watered, weeded, or fertilized.

Photo by Sigal Ben-Shmuel/EKLA

The 2.5-acre park on the Morgan Processing and Distribution facility is the biggest green roof in New York.

The vegetation is a densely planted assemblage of some 25 hardy, low-growing species that have thrived in their few inches of planting material. The plants’ size and modest requirements, however, belie their substantial biological capacities and environmental benefits. Since the roof has been installed, the building’s storm water runoff into the New York municipal water system has been reduced by as much as 75 percent in summer and 40 percent in winter. The U.S. Postal Service estimates that the plants’ ability to cool the roof in summer and insulate it in winter will reduce the building’s energy costs by $30,000 a year.

The sprouting of a large, living roof in midtown Manhattan is a sign that this universally lauded green practice, which has spread rapidly across Europe, is now gaining a serious foothold in the U.S. Although initially more expensive than standard asphalt or shingle roofs, green roofs offer major environmental and economic advantages, from slashing storm water runoff and energy costs, to cooling overheated cities and cleaning their air.

Chicago, which now has more green roofs than any other U.S. city, last year added 600,000 square feet of green roofs and has some 600 projects that will bring its total to 7 million square feet. Washington, D.C. added 190,000 square feet in 2009 and has set a goal of 20 percent green roof coverage by 2020.

In Portland, Oregon, the city provides incentive grants of $5 per square foot for what they call “eco-roofs.” There’s no limit on the size of the roof,

In Europe, Stuttgart and Copenhagen have begun to mandate green roofs on most new construction.

but Tom Liptan, a storm water specialist with the city, says that most of the grants have so far gone to homeowners or to buildings in the commercial district. “It was a cost/benefit evaluation,” says Liptan. “The issue here was storm water. We were trying to find a way to reduce the burden on the city. If we trap it on the roofs, we don’t have to build bigger pipes to carry it or cisterns to store it for treatment.”

Liptan figures that if half the roofs in the city were green, Portland would reduce its storm water burden by some 3 billion gallons, a quarter of the rainfall that hits the city’s roofs annually.

This year Toronto became the first city in the Western Hemisphere to mandate green roofs. New buildings with a total floor area of more than 21,527 square feet will, depending on their size, have to cover from 20 to 60 percent of their roofs with vegetation. A 2005 study calculated that if 75 percent of the flat roofs in the city were greened, Toronto could reap $37 million a year in savings on storm water management, energy bills, and costs related to urban heat island effects.

In Europe, green roofs have been a proven technology for nearly 30 years, as a low flight over Stuttgart, Germany — courtesy of Google Earth — will show. Up Eberhardstrasse approaching Marktstrasse, along Friedrichstrasse to Hauptbahnhopf, the central train station, and north of the city center along Oswald-Hesse-Strasse, there’s often more green to be seen on the rooftops than on the ground (including the vast 27-acre green rooftop of the Daimler company). While most cities in the U.S. measure their green roof area in thousands of square feet, Stuttgart can measure its in millions. Some 20 to 25 percent of the city’s flat roofs are green and, due to a combination of government incentives, tax abatements, and regulations, so are 10 percent of the roofs throughout Germany. Cities such as Stuttgart and Copenhagen have begun to mandate green roofs on most new construction.

The basic green roof consists — bottom to top — of a structural frame covered by a waterproof membrane, an inorganic barrier layer that

‘There’s no place to go in nature to find anything like a green roof system.’

prevents roots from penetrating into the membrane, a layer of gravel or thermoplastic material to provide drainage, a layer of fibrous material for moisture retention, and, finally, the porous planting medium — volcanic pumice, chipped shale, or even ground up roofing tiles. This planting stratum is mostly inorganic, lightweight, and absorbant, while containing enough mineral content to allow plants to grow.

The roof itself can be made of a single large structure or pieced together using modules. There are prefab designs and even those that can be rolled out like sod, with plants already on them. What are called extensive green roofs are usually planted with low-growing plants — heat- and drought-resistant species such as sedums, or grasses such as allium. These roofs are essentially maintenance-free. Green roofs planted with larger and more demanding species — shrubs, trees, flowering plants — require the watering and weeding needed by any garden.

“You’re using a biological system to address urban problems that we’re used to addressing with mechanical systems,” says Ed Snodgrass, owner of Maryland-based Emory Knoll Farms and Green Roof Plants, who has provided over a million-and-a-half square feet of green for some 250 green roofs. These roofs provide a host of benefits, including eliminating the need to develop new ways of containing storm water runoff.

Click to enlarge
Chicago has more green roofs than any other U.S. city — including one atop City Hall.

“I tell developers the green roof is performing a service for the building,” says Snodgrass, author of The Green Roof Manual. “And it can be done with a minimum amount of cost.”

Yet the green roof, Snodgrass points out, is not anything like a natural ecosystem. “Everything is designed — there’s no natural analogue,” he says. “There’s no place to go in nature to find anything like a green roof system.”

While varieties of succulents and cactuses, as well as short grasses from the allium family, have proven to be successful green roof plants, nothing seems to succeed like sedums. A large and diverse genus of flowering plants, with some 600 species, sedums can shut down their systems in extreme heat and drought to keep from losing water to evaporation. As the temperature drops and humidity rises, they can, in a matter of minutes, begin to respire again. “If you wanted to design a plant for the conditions on a green roof,” says Snodgrass, “it would be a sedum.”

Once the green roof has been established, scientists have seen, nature takes its own course. The plants provide their own nutrients and, in more polluted areas, even utilize nitrogen in the city air for growth. Insects that feed on nectar visit or colonize the green roofs and spiders that feed on the insects follow.

Green roofs also reduce the amount of pollutants in the storm water that does run off and provide habitat for birds. Cities struggling with already burdened storm water treatment plants — which means most cities — would welcome the millions, even billions, of gallons of water that green roofs might retain. The roofs could also dissipate the effects of summer temperatures where dense development has created intense heat islands.

The major obstacle to the spread of green roofs is the initial cost, which can be anywhere from $15 to $35 per square foot, some two to three times the

According to a New York study, green surfaces would substantially reduce the city’s heat island effects.

cost of a non-green roof. But as Shalini Mohan — vice president of URS Corporation, which installed the Morgan postal facility’s roof — notes, green roofs last far longer than standard flat roofs. The Morgan’s roof cost $5 million, nearly double what a plain roof would have cost, but whereas a flat roof would have to be replaced in 15 years, the green roof will last 50.

And then there are the benefits reaped by the city. A recent, as yet unpublished, study says that if an estimated 1 billion square feet of New York City’s roofs were greened, the city’s annual storm water flow could be reduced by at least 10 billion gallons, equal to one-third of the city’s combined sewer overflow. In addition, the study states, the green surfaces would substantially reduce the city’s heat island effects, which are expected to worsen with climate change. Under a proposed Green Infrastructure Plan, the city would develop standards for green roof design and implementation, as well as incentives for green roofs.

Chicago’s growing number of green roofs have been built with no city incentives, grants, or tax breaks, according to Larry Merritt, spokesperson for the Chicago Department of Environment. “We led by example,” he says, noting that in 2001 a green roof was installed on City Hall. Since then, the movement has gathered momentum.


The Greenest Place in the U.S.
May Not Be Where You Think

The Greenest Place in the U.S. May Not Be Where You Think

Green rankings in the U.S. don’t tell the full story about the places where the human footprint is lightest. If you really want the best environmental model, you need to look at the nation’s biggest — and greenest — metropolis: New York City.

“Chicago City Hall shares a square block with the Cook County municipal building,” says Merritt. “The county doesn’t have a green roof. And we found that on a hot summer day, the City Hall roof is 80 to 90 degrees cooler than the county’s roof.”

Snodgrass says he’s seen the green roof industry in the U.S. grow substantially over the last several years. According to Green Roofs for Healthy Cities, an industry association, roughly 10 million square feet of green roofs were built in 2009, compared to a million in 2004.

“The biggest obstacle for many is the initial cost,” says Brad Rowe, a professor of horticulture with Michigan State University’s Green Roof Research Program. “But that’s because we tend not to look at the long term. The technology is proven. The economics are clear. It’s not just a feel good effort.”


Yes. Green roof concept is catching up in China as well.

What can green roofs do?

Green roof technology has great potential because of the ability to capture rainwater which can be filtered for drinking water and made available locally at each green roofed structure.
In addition, there are numerous reasons why green roofs should be installed in many parts of the world:
• Reduction of A/C costs by keeping the overall ambient temperature cooler on conventional roofs, temperatures rise to 150-200ºF whereas green roofs remain between 77-90ºF.
• Mimic nature and help maintain a evapotranspiration, which returns water back to the atmosphere and cools the city.
• Serve as a massive biofilter to clean the air of urban soot, dusts and toxins thus mitigating asthma and serious respiratory problems which are not negligible in India and China.
• If the roof can support additional weight for shrubs or trees, green roofs can aid in sequestering carbon.
• Green roofs can also be adapted for growing food.

I have a novel solution to keep the small houses cool in summer in sunbelt countries. On the roof one can spread a polyethylene sheet and put thin layer of soil and grow leafy vegetables whose roots spread horizontally and won’t go deep. There are many leafy vegetables which grow quickly. During rainy season the soil taken off and the polyethylene sheet rolled up and kept for next summer season. This way the house gets cooled naturally and provides extra income for the house owner.

Yet another approach is HYDROPONICS. Hydroponics is popular in countries like USA. Developing countries can practice it to get nutritional vegetables in less space.

Dr.A.Jagadeesh Nellore (AP), India

Posted by Dr.A.Jagadeesh on 02 Feb 2011

31 Jan 2011: Report

In Novel Approach to Fisheries,
Fishermen Manage the Catch

An increasingly productive way of restoring fisheries is based on the counter-intuitive concept of allowing fishermen to take charge of their own catch. But the success of this growing movement depends heavily on a strong leader who will look out not only for the fishermen, but for the resource itself.

by bruce barcott

When it began in the early 1970s, Southern California’s sea urchin fishery was a wide-open free-for-all. State marine managers considered urchins a pest — a threat to coastal kelp beds, which they eat — and divers were given a no-limit harvest. Japan’s robust economy was driving a thriving trade in “uni,” buttery sweet urchin gonads beloved by sushi fanciers. The good money convinced divers like Peter Halmay, then a civil engineer, to quit his day job and dive for urchins full time.

“You go down with a rake and a basket and hand pick ‘em, one by one,” says Halmay, who dives out of an old lobster boat based in San Diego. “Cleanest fishery in the world — our by-catch is zero.”

The open harvest worked all too well. By the 1990s, the sea urchin population had been reduced by 75 percent and showed no sign of leveling off. The state limited the number of urchin licenses, but still the population fell. So Halmay led his fellow divers to agree upon limits among themselves. “We realized that unless we established minimum size limits we were going to fish these things out,” he recalls.

Today the San Diego sea urchin fishery is one of the most sustainable co-managed fisheries in America. Co-management is just what it sounds like:

Community leaders are ‘by far the most important attribute in successful co-managed fisheries,’ says one expert.

Local divers and state officials work together to set limits, and for the most part the divers police themselves. Over the past two decades, co-managed fisheries have emerged as one of the most promising strategies — along with marine reserves and catch shares — to halt the decline of ocean ecosystems worldwide. At least 211 co-managed fisheries now exist worldwide, ranging from Alaska’s billion-dollar Bering Sea pollock fishery to smaller artisanal cooperatives like the abalone harvest along the Chilean coast.

What separates a successful co-managed fishery from a failure? It’s not strict oversight, enforcement, or harsh punishment. It’s Peter Halmay — or rather, the role that he plays.

In a study published earlier this month in Nature, researchers at the University of Washington analyzed 130 co-managed fisheries around the world, looking for the factors that made the difference between success and failure. At the top of the list: Strong, legitimate community leaders like Peter Halmay.

“Community leaders weren’t just important — they were by far the most important attribute present in successful co-managed fisheries,” says Nicolás Gutiérrez, the study’s lead researcher. That community leader usually comes from among the fishers. Like Peter Halmay, it’s someone who’s earned the respect of his competitors and peers, continues to have a stake in the fishery, but doesn’t use his position to line his own pockets. “Having the trust of peers is critical,” Gutiérrez says. “We identified some fisheries where there were leaders, but they were mostly guided by self interest, and they weren’t effective.”

Surprisingly, the support of local authorities — usually government officials — was one of the least important attributes of a successful co-managed fishery. “In much of the world, central governments have no resources for fisheries management, no effective governance, and little impact on what actually happens on the water,” says University of Washington fisheries professor Ray Hilborn, who co-authored the paper with Gutiérrez and Omar Defeo, scientific coordinator of Uruguay’s national fishery management program. “In a place like Indonesia, top-down government control simply isn’t possible, and community-based management is the only real alternative.”

The largest industrial fisheries in the U.S. and Europe employ observers to monitor the catch. But even in developed nations, government agencies don’t have the money to monitor what happens in smaller enterprises like the Southern California sea urchin fishery. Only the fishermen themselves can do that. And to get them to agree, it takes a Peter Halmay to lead them.

“Gutiérrez’s work is important because it actually tests a number of ideas” that have been put forth in a theoretical way, says Donald Leal, a fisheries economist and senior fellow at PERC, the Montana-based Property and Environment Research Center. Leal works with the World Bank on sustainable fisheries projects in developing countries. Specifically, Leal says, the new study bolsters the work of Indiana University political scientist Elinor Ostrom, who won the 2009 Nobel Prize in economics for work that showed how groups using common property could manage it themselves without succumbing to the “tragedy of the commons.” The tragedy of the commons, described in Garrett Hardin’s famous 1968 Science article, says that individuals or groups exploiting a shared resource will, out of their own self-interest, ultimately deplete that resource.

Prior to Ostrom, many economists believed the commons could be solved only through privatization or top-down state control. In her 1990 book Governing the Commons, Ostrom found examples of a third way: self-organized enterprises — groups of fishers, farmers, or ranchers — who voluntarily organized themselves in order to share the short-term sacrifices

Co-management requires lifelong rivals to cooperate and trust one another.

and reap the long-term rewards of their sustainable stewardship of common resources.

Think of a law firm, Ostrom wrote, where individual partners practice on their own but share the rewards of the whole firm’s success. These “private-like” and “public-like” institutions defy easy classification, and each evolves out of its own local ecological, economic, social, and political circumstance. Over the past 20 years, Ostrom’s ideas have been embraced by fisheries policymakers desperate to stop the overfishing that’s led to the crash of marine ecosystems all over the world.

“One of the questions we deal with all the time is, how do you motivate participants in a failing fishery to adopt the changes needed to save it?” says Leal. “Elinor Ostrom looked at fisheries and other natural resources,” he noted, “and derived some common characteristics that led to what she called long enduring systems,” or sustainable, thriving commons. Gutiérrez’s study, Leal says, builds on Ostrom’s foundation by highlighting the importance of what Leal calls “an actuator — a respected leader who can motivate other fishermen to adopt that change.”

As for Ostrom herself, she says she’s heartened by Gutiérrez’s findings. “It was very exciting to see the findings about trust, communication, commitment, and respect for leaders being the most important attributes leading to successful fisheries co-management,” she said recently. Fishing culture has long valued independence, secrecy, and competition. Co-management requires lifelong rivals to cooperate and trust one another. “These aren’t situations where everybody gets together for dinner on a Saturday night and solves the problem,” Ostrom added. “They’re complex, and they take time. You’ve got to trust the other fishers, and that’s why a leader is so important. You’re looking for a person who’s built trust and social capital by solving previous problems in the community.”

Though there are common characteristics, there’s no one-size-fits all model for this “actuator.” Sometimes it’s not even a fisherman. Take, for instance, the southern Belizean town of Punta Gorda, near the Guatemalan border. About 100 local fishermen there make their living by catching grouper, snapper, and mackerel a few miles offshore. It’s an artisanal fishery typical in the non-industrial world. In the predawn hours, fishers head out in pangas or skiffs powered by small outboard motors. They use fish pots and hand lines. Their catch is featured at the local street market, sold to a commercial processor, or taken home for dinner.

Global forces come to bear on Punta Gorda’s tiny fishery. International conservation groups like the WWF and the Environmental Defense Fund are working to protect the Mesoamerican Reef, the 700-mile system that runs from Mexico’s Yucatan Peninsula to northern Honduras — a reef that sustains Punta Gorda’s fishery. In recent years, Jamaican fishermen, who have notoriously overfished their own waters, have taken to raiding the waters off Punta Gorda. The Belizean government lacks the resources and legal authority to keep the foreigners out.

But there is a leader here — or rather, leaders. In 1997, Wil Maheia, a local Punta Gorda man educated at the University of Idaho, created the Toledo

Rangers patrolled local waters to make sure everyone fished with legal nets in legal spots.

Institute for Development and Environment (TIDE). TIDE and the Belizean government became partners in managing the Port Honduras Marine Reserve, a newly created conservation area. Maheia worked with local fishermen to make sure the reserve enhanced their businesses, instead of ending them. TIDE-funded rangers patrolled local waters to make sure everyone fished with legal nets, in legal spots, at legal times.

Not just an environmental group, TIDE became a beneficent force in the community. The group sponsored youth camps, offered scholarships, and organized soccer leagues. And Maheia became the public face of sustainable marine co-management in Punta Gorda, trusted because of his deep ties to the town and his group’s work on the community’s — and the fishermen’s — behalf.

Maheia retired from TIDE a few years ago, but his role is being carried on by Celia Mahung, the organization’s current executive director. Recognizing the importance of fisher-to-fisher communication, she’s created a community stewards program in which experienced local fishermen receive policy-level training in fisheries management. “We saw there were a few resource users who were already practicing stewardship on their own,” Mahung says. “They were fishermen who’d call up and say, ‘We ought to do something about this.’”

Those stewards have become community leaders, speaking at public meetings, to schoolchildren, and to other fishermen about co-management and sustainable fishing practices. Today they’re leading advocates for a catch shares system, which the Belizean government is now working to institute. (In a catch shares system, fishermen are allotted a secure percentage of that season’s total allowable catch, usually based on their past seasonal average.)

There’s an element of entrepreneurship that often goes hand in hand with the leadership role identified by Gutiérrez in the Nature study.

Six years ago, for instance, Peter Halmay got the idea to have sea urchin divers start collecting data on their catch. They recorded urchin sizes, dates, and locations. “One guy, he’s measured 100,000 sea urchins in the last few

After a while the whole community started getting involved, realizing the resource was theirs.

years,” Halmay says. That data has proven invaluable. “The state [the State of California Department of Fish and Game] is being pressured to step up their fishery management, but they’ve got no money,” Halmay says. The urchin fleet’s numbers showed that its harvest remained healthy and sustainable. “Without that data, the state might have defaulted to the precautionary principle and just shut us down, not let us fish at all,” says Halmay. (This arrangement, of course, still requires some trust-but-verify work on the part of state fisheries managers.)

For his part, Wil Maheia was instrumental in opening up new markets for the fishermen of Punta Gorda. Years ago he saw an opportunity for local fishermen to make good money guiding foreign sport fishermen — a small but lucrative industry that benefitted from the Port Honduras Marine Reserve. For those who were interested, Maheia arranged for guide training and connected local fishing guides to nearby high-end fishing lodges.

In San Diego, Halmay and the fishery co-management association he helped form, the San Diego Watermen’s Association, have also expanded their markets. “We realized our old business model wasn’t very good,” he says. In the past, sea urchin divers would sell all their catch to uni processors, who didn’t differentiate price-for-quality. An urchin was an urchin. “But we realized there was a market for the highest quality sea urchins — that the very best could command a higher price.” So they started a dockside market.

“All of a sudden people started coming by,” Halmay recalls. “Local Italians love ‘em, but they don’t want them processed. They like them whole. They cut the urchin open and eat it on bread.” Restaurants also came calling. A local Italian bistro, Baci Ristorante, now serves such renowned sea urchin dishes that Seattle Mariners outfielder Ichiro Suzuki is known to stop in for the uni when his team’s in town.


Hatch-22: The Problem with
The Pacific Salmon Resurgence

The Problem with the Pacific Salmon Resurgence

The number of salmon in the Pacific is twice what it was 50 years ago. But there is a downside to this bounty, Bruce Barcott writes, as growing numbers of hatchery-produced salmon are making it hard for threatened wild salmon species to find enough food to survive.

“Peter Halmay is a great example of this kind of leader,” Nicolás Gutiérrez says. “He used data collection to empower others in the fishery. After a while the whole community started getting involved, realizing that the resource was theirs” to harvest, conserve, and co-manage.

One thing Gutiérrez’s study doesn’t touch on, though, is a key ingredient that Halmay said made a big difference: Information transfer. Fishermen often live in closed-loop information systems. They know a hell of a lot about what’s going on in their waters, but little about what’s happening up the coast or around the world. “We had a visit from a fellow who helped start fishing cooperatives in Japan,” Halmay says. “Then we started reading about what they were doing in Chile and some other places where fishermen were taking charge, doing the management themselves. We said, ‘Well, we can do that!’”

And, with Halmay’s ideas, energy, trusted intentions, and verbal dexterity leading the way, they did it.


Fish Aggregating Devices (FADs) have proved very successful in the Maldives, where there is a countrywide FAD installation programme by the Ministry of Fisheries and Agriculture (MOFA) underway. The main reason for the success of FADs in the Maldives is their applicability to the existing fisheries. With the motorization of the fishing fleet, the efficiency and range of operation of the fleet has increased.

Dr.A.Jagadeesh Nellore (AP),India

Posted by Dr.A.Jagadeesh on 02 Feb 2011

20 Jan 2011: Report

Green Energy’s Big Challenge:
The Daunting Task of Scaling Up

To shift the global economy from fossil fuels to renewable energy will require the construction of wind, solar, nuclear, and other installations on a vast scale, significantly altering the face of the planet. Can these new forms of energy approach the scale needed to meet the world’s energy demands?

by david biello

From the dust-blown steppes of Inner Mongolia to the waters off Shanghai, China installed more wind turbines in the first half of 2010 than any other country — 7,800 megawatts of potential power production, or more than the United States, the European Union, and India combined. In fact, in northeast China alone, autumn and winter winds now produce some 17 billion kilowatt-hours of electricity, roughly 5.5 percent of the total power generation in the region. That’s up from 534 million kilowatt hours just five years ago.

But despite this rapid progress, wind energy still only generates a tiny fraction of China’s electricity. Indeed, even with aggressive government backing and green energy mandates, such “new energy” — including wind, solar, nuclear power plants, and biomass — accounts for less than 3 percent of China’s electricity production, compared to more than 70 percent provided by coal, which produces roughly 3 metric tons of carbon dioxide for every metric ton of the dirty, black rock burned. And as China’s economy continues to expand at a dizzying rate for the foreseeable future, wind and other renewable sources of energy will not even be able to keep pace with new demand, meaning fossil fuel burning will continue unabated.

This is hardly unique to China. In the U.S., electricity produced from the breeze has increased 13-fold in the past decade, yet still only provides 2.3 percent of the country’s electricity — compared to just under 50 percent provided by burning coal. Even Denmark, which has done more than any other country to boost wind power, struggles to integrate an intermittent generating resource into a grid whose customers expect the lights or the television to come on whenever they flick the switch.

As the world attempts to wean itself from fossil fuels — a result of the converging desires to combat climate change, improve energy security, and

‘We need to replace all of the power-producing infrastructure that we have today within 40 years,’ says one expert.

create green jobs — renewables such as the sun, wind, water, and hot rocks will play a larger role. So will energy sources, such as nuclear and natural gas, that are cleaner than the current favorites, coal and oil. The question is: Can any of these resources — or even all of them put together — begin to approach the scale needed to transform the world’s energy supply?

And even if the world’s economies can muster the resources and willpower to wean themselves off fossil fuels, how many decades will it take? And can we move fast enough to stave off the potentially calamitous effects of climate change?

“Renewables are growing at fantastic rates compared to conventional resources,” says David Rogers, general manager for climate change at the oil giant, Chevron. But “while it’s growing like gangbusters, it’s starting from such a small base that by 2030 it still takes a small part of the energy space.”

To meet a proliferating set of international goals, such as Germany’s plan to derive 80 percent of its electricity from renewable sources by 2050, will require completely changing the present energy mix. Despite more than 21,000 wind turbines and 13 million square meters of solar installations, Germany still gets more than 50 percent of its electricity from burning fossil fuels, including lignite, the most polluting form of coal.

“In some real sense, we need to replace all of the power-producing infrastructure that we have today within 30 or 40 years,” says engineer Saul Griffith of California-based Other Lab, an engineering and design firm working on renewable energy projects, among other pursuits. “The options that we have that are non-carbon [dioxide] producing are nuclear power, solar power at a very large scale, wind power at a very large scale, and geothermal at a very large scale — and then perhaps biofuels or carbon sequestration on existing power plants.”

Wikimedia Commons

If the world makes the transition to renewable energy, wind turbines will become a common feature of many landscapes.

In fact, at the global level, in order to shift away from a world that gets 81 percent of its energy from fossil fuels and to cut emissions of carbon dioxide to just 14 gigatons per year, here is what the International Energy Agency says will have to be built every year between now and 2050: 35 coal-fired and 20 gas-fired power plants with carbon capture and storage; 30 nuclear power plants; 12,000 onshore wind turbines paired with 3,600 offshore ones; 45 geothermal power plants; 325 million square meters-worth of photovoltaics; and 55 solar-thermal power plants. That doesn’t even include the need to build electric cars and hydrogen fuel cell vehicles in order to shift transportation away from burning gasoline.

In addition, if the world’s economies hope to wean themselves from fossil fuels, they will have to significantly improve energy efficiency and begin to harness power from sources such as waste heat from factories.

One thing is certain: If the global economy does succeed in making the transition to renewable energy, the face of the planet will be significantly changed, with solar energy farms and wind turbines a common feature of many landscapes and seascapes.

“If 10 percent of the U.S. electricity generated in 2009... were to be produced by large wind farms, their area would have to cover at least 22,500 square kilometers, roughly the size of New Hampshire,” writes

‘It’s not going to be easy to make an energy plan that adds up, but it is possible,’ one physicist says.

environmental scientist Vaclav Smil of the University of Manitoba in his book, Energy at the Crossroads. “These new energy infrastructures would have to be spread over areas ten to a thousand times larger than today’s infrastructure of fossil fuel extraction, combustion and electricity generation…. This is not an impossible feat, but one posing many regulatory, technical and logistic challenges.”

“Can we do this or not?” Chevron's Rogers asks. “Even at the best time we ever had we only did 20 to 25 nuclear power plants in a year... We need 325 million square meters [of photovoltaics] annually. We’ve done maybe 10 percent of that in our best year, which was last year.”

But there is reason for guarded optimism. Even in the throes of the Great Recession, renewables accounted for more than 50 percent of newly installed generating capacity in the U.S. and the European Union, while China added 37 gigawatts of mostly wind and hydropower in 2009, according to the United Nations Environment Program.

“It’s not going to be easy to make an energy plan that adds up; but it is possible,” says physicist David MacKay of the University of Cambridge, an expert on scaling up renewable energy. “We need to make some choices and get building.”

When it comes to such a large-scale shift in energy supplies, few places face more of a challenge than the United States. Americans burn through nearly 6.4 billion barrels of oil and 1.1 billion metric tons of coal per year on our way to getting 83 percent of our energy fix from fossil fuels. Renewable resources, such as the sun, the wind, the flow of rivers and fuels derived from crops supply just 8 percent of our energy needs. Take away ethanol and hydropower, and the sun, the wind, and geothermal power supply less than 1 percent of the U.S.’s total energy use, including gasoline consumption.

Just to supply one-quarter of its current energy mix from a resource that emits far fewer greenhouse gases — nuclear power — the U.S. would need to build 1,000 one-gigawatt nuclear reactors by 2050. Yet construction has begun on only two nuclear reactors in the U.S. since 1974. And just to power an electric car and truck fleet to replace the U.S.’s current gas and ethanol-fueled one would require 500 new nuclear power plants. There are currently 442 reactors in the entire world, of which the U.S. has 104 — the most of any nation.

U.S. attempts to wean itself from fossil fuels have never fared well, yet the Obama administration has committed internationally to an 80 percent drop in greenhouse gas emissions by 2050. Either alternative energy supplies will need to ramp up from nearly zero to almost 100 percent in just four decades, or large-scale carbon capture and storage will be required, including pulling CO2 out of the air after it has been put there by all of our automobiles. In fact, simply removing one gigaton of carbon from the atmosphere would require 273 coal-fired power plants with complete carbon capture and storage. At present, there is one in the U.S., capturing just 1.5 percent of its emissions.

“We are talking about a transformation across the entire country,” Federal Energy Regulatory Commission (FERC) chairman Jon Wellinghoff said in an interview with Yale Environment 360. “We are talking about potentially tens of thousands of new transmission lines to ultimately move large amounts of wind, solar, and other resources to loads. We are talking about in the scale of billions of dollars of investments in smart-grid technologies, all the way from the consumer level up through to the transmission and generation level.”

Assuming the U.S. will require roughly 4 terrawatts of power by 2050 (a conservative estimate, given that we already use more than three),

To meet present global consumption would require covering 1 percent of Earth’s surface with photovoltaic devices.

replacing all that fossil fuel would require at least 4 million wind turbines — necessitating building 12, three-megawatt wind turbines every hour for the next 30 years, according to Griffiths. The numbers are similar for solar — 160 billion square meters of photovoltaic cells or concentrating mirrors. “We need to be making a square yard of solar cells or mirrors every second for the next 40 years to install that much in North America,” Griffiths calculates.

It’s not just a matter of making the necessary equipment, it’s also a question of finding the space for it. A coal-fired power plant produces 100 to 1,000 watts per square meter, depending on the type of coal it burns and how that coal is mined. A typical photovoltaic system for turning sunlight into electricity produces just 9 watts per square meter, and wind provides only 1.5 watts per square meter.

The challenge is worse for smaller countries: the United Kingdom would have to cover its entire landmass with wind turbines to provide enough electricity for the current Briton’s average consumption — roughly 200 kilowatt-hours per day, according to MacKay, the Cambridge expert.

Although daunting, the challenges of installing new energy technologies on a mass scale are by no means impossible. In the first half of the 20th century, it took the U.S. 45 years to increase its use of oil until that fossil fuel represented 20 percent of the total energy used. At the same time, the U.S. built a sprawling gasoline-fueling station infrastructure, the rudiments of a national electricity grid, thousands of miles of telephone lines, airplanes and airports, interstate natural gas pipelines, and local delivery infrastructure for home heating — and rolled out all the appliances (refrigerators, radios, televisions, etc.) of the modern age — all in the same few decades, at the same time. In other words, the U.S. seems to have “scaled up,” in the parlance of engineers, pretty rapidly in the past.

Transforming the global economy to run on renewable energy would require a similarly massive effort. For example, to provide the energy equivalent of present global consumption would require covering 1 percent of the Earth’s surface with photovoltaic devices, according to chemist Nathan Lewis of the California Institute of Technology. That’s less than the land area currently covered by cities, but a huge chunk of territory nonetheless.

“You can actually farm, you can actually graze, you can actually do things around that [wind] turbine versus if you are taking the top off a mountain

If this great energy transformation eventually comes, it will take decades to complete.

to produce some coal,” FERC’s Wellinghoff notes. “Ultimately, we are going to have to accept the fact that wind turbines and solar systems are going to take up fairly large pieces of land. But, fortunately, we have a lot of land in this country and we have the ability to have dual use of that land.”

But the U.S. also leads the major nations of the world in per capita consumption of energy. The average American used 7.2 metric tons of oil-equivalent in 2009 (a number that, to be fair, has gotten slightly better of late, down from 8.5 in 2005.) That’s double the amount used by the average citizen in Europe, and five times the global average.

To put it another way, the average American uses 250 kilowatt-hours per day for “transportation, heating, manufacturing, electricity, and so forth,” writes MacKay. “That’s equivalent to every person having 250 40-watt light bulbs switched on all the time.” Energy efficiency might bring that consumption as low as 168 kwh per day, according to MacKay. But that still means each American would require 80 square meters of photovoltaic panels, plus biofuels from energy crops on 4,000 square meters of land. In addition, the U.S would need to build one 2-megawatt wind turbine for every 300 Americans, plus one 1-gigawatt nuclear power plant for every city the size of Boston.

On the grander scale, more than half of the energy used in the U.S. — 56.3 percent — is wasted. That’s a result of the essential inefficiency of burning coal in a power plant or gasoline in an automobile engine, or even transmitting electricity over vast distances.

Industry is beginning to make use of this waste — a steel plant in Indiana employs the waste heat from a coal coking plant to generate electricity, enough to help run its steel rolling machines in another adjacent facility. And while U.S. energy use has grown over the past four decades, three-quarters of that growth has been met through gains in energy efficiency, not by burning additional fossil fuels, according to a 2008 report from the American Council for an Energy-Efficient Economy (ACEEE). The energy used to produce every dollar of U.S. gross domestic product fell from 18,000 Btus in 1970 to just 8,900 Btus in 2008.

“The energy-related challenges of the 21st century require a dramatic shift in direction — from an emphasis on energy supply to an emphasis on energy efficiency,” says Jon “Skip” Laitner, ACEEE director of economic analysis. “The greatest American success story in dealing with energy in recent decades is also the least understood and the most invisible.”


CO2 Capture and Storage
Gains a Growing Foothold

Rising Seas

The drive to extract and store CO2 from coal-fired power plants is gaining momentum, with the Obama administration backing the technology and the world’s first capture and sequestration project now operating in the U.S.

In fact, researchers at Lawrence Berkeley National Laboratory estimate that waste heat from factories, oil refineries and other industrial facilities holds the potential for as much as 95 gigawatts (the equivalent of 95 nuclear power plants) of new electricity, which is cheaper to capture than building a new coal-fired power plant.

If this great energy transformation eventually comes, it will take decades to complete. But, as FERC’s Wellinghoff notes, “The scale is very large but, fortunately, it is something we can do incrementally and it is something that we have already started.”

If society’s efforts were turned in different directions, shifting from making fewer consumer products to making more devices to capture renewable energy, the transition might ultimately fuel itself. After all, beverage makers now produce some 300 billion aluminum cans per year, Griffiths notes, which is enough production capacity to manufacture 100 or 200 gigawatts of solar thermal annually. “So we could do 1 terrawatt of solar in 10 years if Pepsi and Coca-Cola and all the breweries became solar companies,” he says. “We have the industrial scale. We are just right now prioritizing what we want to make with it and we are making disposable aluminum cans instead of solar mirrors. That gives me reason for optimism. We can do it.”


Though the forecast is very optimistic,Renewable Energy can only supplement conventional energy but not replace it.

Here are achievements of Renewables in India:

New & Renewable Energy

Annual achievement 2010-11 and Cumulative achievements as on 30.06.2010


Sources / Systems

Achievements during 2010-11 (upto 30.06.2010)


Achievements (upto 30.06.2010)

I. Power From Renewables

A. Grid-interactive renewable power


Biomass Power (Agro residues)

45.50 MW

901.10 MW


Wind Power

202.73 MW

12009.48 MW


Small Hydro Power (up to 25 MW)

31.64 MW

2767.05 MW



67.50 MW

1411.53 MW


Waste to Energy

7.50 MW

72.46 MW


Solar Power

2.00 MW

12.28 MW

Total (in MW)

356.87 MW

17173.90 MW

B. Off-Grid/Distributed Renewable Power (including Captive/CHP Plants)


Biomass Power / Cogen.(non-bagasse)

6.00 MW

238.17 MW


Biomass Gasifier

4.00 MWeq.

125.44 MWeq


Waste-to- Energy

6.00 MWeq.

52.72 MWeq


Solar PV Power Plants

0.0 MWp

2.92 MWp


Aero-Generators/Hybrid Systems

0.0 MW

1.07 MW


16.00 MWeq

420.32 MWeq


Remote Village Electrification

208 Villages & Hamlets

6867 villages & Hamlets

III. Decentralized Energy Systems


Family Type Biogas Plants

0.07 lakh

42.60 lakh


SPV Home Lighting System


6,03,307 nos.


Solar Lantern


7,97,344 nos.


SPV Street Lighting System


1,19,634 nos.


SPV Pumps


7,334 nos.


Solar Water Heating - Collector Area

3.53 Mln. sq.m.

MWeq. = Megawatt equivalent; MW = Megawatt; kW = kilowatt; kWp = kilowatt peak; sq. m. = square meter


Bright news came out of the Indian solar market yesterday as the county’s top energy officials announced that India is capable of reaching its 2015 renewable energy goal. The goal, set by India’s National Action Plan on Climate Change (NAPCC), calls for meeting 10 percent of the nation’s energy needs with renewables.
India has a total generating capacity of over 1.5 million megawatts (MW), according to Pramod Deo, Chairman of the Central Electricity Regulatory Commission (CERD). Right now, renewable energy accounts for over ten percent of that capacity — about 17,000 MW — but only contributes four percent to the nation’s total power generation. Renewable energy supply in India could reach nearly 48,000 MW, with right around 4,000 MW coming from solar alone, according to a study done by the Central Electricity Regulatory Commission (CERC).

The government is also offering a generation-based incentive in order for India’s solar market to meet a 2022 target of 20 gigawatts (GW). R. Chirstodas Gandhi, chairman and managing director of the Tamil Nadu Energy Development Agency (TNEDA), has another idea of how India can meet this goal. He says the country should look into small, individual renewable energy projects to meet energy requirements in remote locations around the country.
Whichever way India chooses to go, its decisions have proved to be paying off so far. The country is one of nine that are set to surpass 250 MW in solar photovoltaic (PV) demand in 2010.(

Dr.A.Jagadeesh Nellore (AP), India

Posted by Dr.A.Jagadeesh on 29 Jan 2011

Steady Growth of Wind Industry
Moves EU Closer to Green Goals
Europe is in the midst of a wind energy boom, with the continent now installing more wind power capacity than any other form of energy. In an interview with Yale Environment 360, the European Wind Energy Association's Christian Kjaer describes his vision of how wind can lead the way in making Europe’s electricity generation 100 percent renewable by 2050.
Today, only five percent of Europe’s electricity comes from wind. But that will not be the case for long. For the past two years, 40 percent of all new electricity generating capacity in Europe came from wind turbines. From Spain to Sweden, so many new turbines are being erected that Europe is on target to produce 15 percent of its electricity from wind by 2020. By 2050, half of Europe’s electricity is expected to come from wind.
In an interview with Yale Environment 360 senior editor Fen Montaigne, Christian Kjaer — CEO of the European Wind Energy Association, an industry group —

Christian Kjaer
describes the combination of government policies, entrepreneurial vision, and public support that have enabled wind to become Europe’s leading form of green energy. The 27-member European Union has passed a host of progressive policies — including tax credits, financial incentives, and priority access for renewable energy to the electricity grid — that have encouraged the growth of wind, solar, and other forms of green energy. But the EU also wields a stick, requiring member states to set renewable energy targets and retaining the right to sue those countries that fall short.
Increasingly, says Kjaer, as old power plants fired by coal and natural gas reach the end of their lives, they are being replaced by wind and solar power. The economic benefits of this transition, says Kjaer, are indisputable, with nearly 200,000 people currently employed in the European wind power sector. By 2020, Kjaer estimates 450,000 Europeans will have jobs in the wind power industry.
Kjaer is confident that, as green energy competition from Asian nations intensifies, Europe can retain its edge, thanks to its high-quality manufacturing sector and strong government support. “The winners of tomorrow’s energy wars,” he says, “are going to be those who understand how to develop new technology, deploy new technology and get the benefits of exporting that technology to the rest of the world.”

Yale Environment 360: I was wondering if you could paint a picture of the state of the European wind industry and describe what kind of growth you’ve been experiencing in recent years.
Germany, Denmark, and Spain are leading because they started early and are reaping the benefits.”
Christian Kjaer: For the past two years, the 27 member states of the European Union, taken as one, have installed more wind power capacity than any other power-generating capacity. So wind energy is currently meeting 5 percent of the electricity demand in the European Union. But in terms of new power plants, new capacity — which of course also is an indication of new jobs and economic activity in the power plant manufacturing business — 40 percent of all new capacity last year was wind. And if you add other renewables — and this is primarily PV, solar photovoltaics — 63 percent of all new capacity installed last year was from renewables. So I think that’s the most significant.

It’s even more telling that more than 75 percent of the [wind] installations last year were in five countries: Spain, Germany, Italy, France, and the U.K. We’re installing 40 percent [of new capacity], and we’re actually doing that not even looking at all the member states that have the potential to install wind energy.

In terms of the overall status of the power market, we need the European Union to install new capacity between now and the next 10, 15 years equal to about 50 percent of currently installed capacity. We need to replace existing power plants that are getting old, but also to meet expected increases in demand in the future. We believe it’s a great opportunity to make a real change in the way we supply our energy. Because we need to do investment in new power plants anyway, so we might as well invest in technologies that are compatible with the very strong and changed political agenda on renewables and on reducing carbon emissions.

e360: When you talk about the 50 percent installed capacity, are you talking about new wind generation meeting that requirement, or all renewables?

Kjaer: The European Union adopted last year legislation which mandates that each member state has a specific target for its share of renewable energy in the energy mix by 2020. And what that means collectively is that we need to increase the share of renewables in electricity from currently about 15 percent — that includes 10 percent for large hydro and about 5 percent wind energy — to 35 percent by 2020. Our large hydro can’t increase much more, because it’s already utilized. So that means if you take large hydro out, you need to increase non-large hydro renewables from currently 5 percent to about 25 percent. And of course wind energy will be one of the big contributors to that.

e360: Can you briefly sketch out how you think, in the wind sector, those very ambitious goals can be met?
The U.S. framework for investing in renewables is very unstable — it cannot be predicted more than one or two years ahead.”
Kjaer: We believe that we will reach about 230 gigawatts of wind by the end of 2020, and that’s up from approximately 80 gigawatts today. That will produce somewhere between 14 and 17 percent of our electricity, depending on the electricity demand. We need to install approximately 9.5 gigawatts of new wind capacity each year between now and 2020. Now, given that we installed more than 10 gigawatts last year, technically this is not a big challenge. If we just do what we’ve been doing the last two years in terms of new installation, then we will have 15 percent of our electricity coming from wind energy in 2020.

Now we believe that you can reach a higher level, and the European Commission has also indicated that it believes that wind energy could contribute 20 percent of European electricity in 2020. But then we really need to make a serious effort in terms of changing the way we operate our grids. Also, we would need to be a bit faster in developing an offshore grid for utilizing the offshore wind energy. That will require some additional efforts from politicians mainly, related to optimizing and expanding our grid infrastructure to accommodate a larger amount of variable wind power in the system, and also other renewables.

e360: Why is it that wind has taken off at such a respectable rate, ahead of solar?

Kjaer: The reason wind will be the main contributor to reaching these targets is that onshore wind is the cheapest of the new renewables. So the majority of this will be met by wind turbines on land. Offshore is still more expensive, but we do expect that to play an increasing role as well. But in terms of wind versus photovolyaics, we’re still significantly lower in terms of producing a kilowatt-hour of electricity.

e360: Can you say a few words about this proposed North Sea supergrid and how important that might be?

Kjaer: There’s a very strong [desire] to develop offshore wind energy. So one main element of the North Sea supergrid is that we need to accommodate a large expansion of one of our biggest future energy sources in order to avoid increasing our [oil] imports from unstable regions of the world.
We expect that with the 2020 targets we would be employing about 450,000 people [in Europe].”
One of the main reasons for the strong political support for a supergrid is also that we want to create an internal [European] market for electricity, which of course, in the end, should give consumers the most affordable electricity. That’s the whole idea about the internal market, is that it would create the free movement over borders of goods, services, and in this case electricity at the lowest cost. And in order to create an internal market for electricity you need the infrastructure, just as you need roads to move goods around the European Union.

The European Union and the United States are very similar here. In the United States you have the same challenge, that electricity is governed mainly at the state level. And it’s the same problem we have in the European Union, getting the member states to cooperate on cross-border issues, the same as between the states in the United States.

What is really needed is for member states to have much stronger collaboration, and what we have seen also recently is that a group of ten countries surrounding the North Sea, and also countries that are a bit further away from the North Sea which have an interest in it as well, have formed a group discussing, at the government level, how should we create a North Sea grid and how should we integrate offshore wind energy into that grid?

e360: When you look at the five countries that you listed that are really leading the way in wind so far, why is it that they have become the leaders? And, secondly, what government policies are necessary to have a robust wind industry?

Kjaer: Of the five countries I mentioned, there are two main groups. Germany and Spain — and we can add Denmark there, as well — started early. Spain and Germany are still large contributors to wind energy installations in the European Union. Spain was 24 percent of the market last year and Germany was 19 percent of all installed capacity in Europe last year. Denmark is not because it’s a small country, but they already get more than 20 percent of their electricity from wind energy. So there’s also a size element in this. But Germany, Spain and Denmark are leading because they started early, starting with Denmark back in the ‘80s and then also Spain and Germany in the ‘90s. They are now reaping the commercial benefits of starting early. And this is also where you see the majority of wind turbine manufacturers, but also further down the supply chain, with German, Spanish, and Danish companies dominating.
We need to beat the real competition, which is fossil fuel and nuclear.”
And the second group of countries — the U.K., France, and Italy — each installed approximately 10 percent of the European market last year. Of course, they are there also because their countries are very big compared to many of the other European Union countries. Both Italy and France installed about a thousand megawatts the last couple of years, and it could go much, much faster. Those countries that are really growing fast are countries like Portugal. It installed 7 percent of all [EU] capacity last year, but that’s quite a lot for a country the size of Portugal, and it’s one of the countries getting the largest share of electricity from wind energy in the European Union.

e360: In terms of the policies that need to be in place for a robust wind industry, what would you say are the top three or four, keeping in mind lessons the U.S. might take from what Europe has done in wind so far?

Kjaer: I think if there were one word to communicate to U.S. policymakers, it is that you need stability. I’m saying that because the U.S. framework for investing in renewables is very unstable — I mean, it cannot be predicted more than one or two years ahead. And that also means that the United States is not reaping the job creation benefits of wind energy, because a lot of components, a lot of manufacturing is imported because no one’s going to invest in a factory in the United States if they don’t know how the market looks beyond the next two years. So a long-term stable framework is what is most desperately needed in the United States. What has given rise to those [EU] markets is that you have stable frameworks and they have been long-term. The problem in the U.S. is that the framework expires every year or every second year.

e360: In terms of tax credits?

Kjaer: Tax credit, yes. Tax credit is a major source of uncertainty in the U.S. The second element of any effective legislation should be access to the grid. And what European legislation does, it mandated all 27 member states to give priority access to wind energy, which means that if you have a wind farm and a gas plant, and they’re planned projects, the wind energy should be connected first. And also, if you have plants operating on the system, electricity from the renewables plant gets fed into the grid first. And the third element is administrative procedures, building permits, et cetera. We have examples in some European countries where you need 50 different institutions to agree on approving a wind farm. So what we are promoting is one-stop shops, that you can send in an application somewhere, that there’s a deadline for how fast this application should be processed rather than having it tied up for years.
We believe we can meet 50 percent of Europe’s electricity demand by 2050 with wind energy.”
So those are the three elements: the financial predictability, the grid access, and the administrative procedures, combined with an overall target. In the case of the European Union, the national targets are mandatory, meaning that if a member state falls short of its target, it can be taken to the European Court of Justice. The European Commission can sue a member state that doesn’t meet a target, and that was one of the strongest elements of the directive that was passed.

e360: Do you feel that the European wind industry has lived up to the promise of creating new jobs?

Kjaer: There are about 190,000 people employed in the European wind energy sector. This is the employment that can be attributed to the manufacture of the turbines installed in Europe, plus the maintenance of those turbines. So, for instance, the world’s largest wind energy company is a Danish company called Vestas. This doesn’t include jobs created in Europe from wind turbines put up in the United States. So the turbines put up in the 27 member states of the EU, that’s about 190,000 jobs. The majority of those are in onshore, of course. In the past five years we have created approximately thirty new jobs every day of the year. So that’s the level of employment we’re talking about. We expect with the 2020 targets — if we’re meeting those targets, we would be employing about 450,000 people in the European Union. And almost 300,000 of those would be in onshore and the rest in offshore.

e360: So this element of green energy that President Obama’s been trying to sell, that it can be an engine of job creation, you feel has been shown in Europe.

Kjaer: There’s no doubt that it’s an engine of job creation. And if you go to Germany or to Denmark or to Spain, wind turbine manufacturing and all the follow-ons from that is an enormous part of their economies — certainly in Denmark, which is a small country. The United States, the European Union, and the vast majority of countries in the world are importing energy. And the share of imports is increasing. In Europe we import more than 50 percent of our energy. I think it’s getting clearer to many people in the world that rather sending the citizens’ money abroad to pay for imported fuels, it makes much more sense to put the money to work at home, and then export technology.

And I think this is what we will see, which will be the big difference between the last century and this century. In the last century, those who won the energy wars were those who either had the resources or controlled them in some way, and the winners of tomorrow’s energy wars are going to be those who understand how to develop new technology, deploy new technology and get the benefits of exporting that technology to the rest of the world. They’re going to need it very soon, because the fuels are not going to last forever and no one knows what the cost of those fuels will be 5, 10, 15 years from now.

e360: Do you feel that European companies are well-positioned to compete against Chinese wind turbine manufacturers?

Kjaer: It’s important to say that there’s a lot of talk about Chinese manufacturers, but it’s not only about increased competition from China. Japan — Mitsubishi has been in this for a long time. South Korea is moving, India has one of the largest wind companies in the world. So there are challenges to the European leadership position. That competition makes us all stronger. And we need that competition in order to beat the real competition, which is fossil fuel and nuclear and other ways of producing electricity.
With a Boost from Innovation,
Small Wind Powers Ahead
New technologies, feed-in tariffs, and tax credits are helping propel the small wind industry, especially in the United States. Once found mostly in rural areas, small wind installations are now starting to pop up on urban rooftops, Alex Salkever reports.
E360: As the wind industry grows onshore and offshore in Europe, how big of a problem is it that, with the spread of turbines on the landscape and the seascape, the public may become more opposed to the expansion of turbines in many areas?

Kjaer: It is an issue. In some countries it’s a significant issue, and the problem is related to NIMBYism, or “not in my back yard.” When you take overall polls on people’s attitudes towards different energy sources, solar always comes first [in popularity], wind comes second, and then all the others afterwards. So, in general, when we see the opinion polls in the European Union, it’s always between 75 and 85 percent that think this is a very, very good idea.

Now, the problem comes when you start down at the project level. There have been many polls suggesting that you poll people prior to the turbines being built and after they were built, acceptance actually increases dramatically after the turbines are built. And this is because people are concerned about the unknown. That’s just a part of human nature. In some countries it’s a bigger problem than in other countries. Onshore, in the U.K., is very difficult because of local opposition.

But it’s my feeling that the concern from locals is biggest in the beginning of a new market taking off. So the first thousand megawatts are much more difficult to install than the next thousand megawatts. Because people get used to them, they understand that they don’t make noise anymore — the turbines twenty years ago made quite a lot of noise, today you can’t hear them, almost, if you’re more than two hundred meters away. So it is an issue, and we have a responsibility as a sector to inform people [and] maintain the dialogue with local communities.

e360: My final question is, what is your industry’s goal for 2050 in terms of what percentage of electricity production would come from wind? And given what you’ve seen so far and given the 2050 goal, has this given you a hope that it is possible for our societies to move off of fossil fuels?

Kjaer: Yes. We believe we can meet 50 percent of Europe’s electricity demand by 2050 with wind energy. Denmark is currently at 20 percent — they have an aspiration to reach 50 percent in Denmark by 2020 or 2025. Can we power our economy solely on renewables? I certainly believe so, and this goes back to something I said at the beginning of this interview. Almost two-thirds of our new capacity is from renewables. That figure was about 20 percent in the year 2000. So in nine years we’ve gone from 20 percent to 62 — by 2020 of course we can get to 100 percent of new capacity. And if we can get in 2020 to a situation where all new capacity is renewables, then we will, by definition almost, have 100 percent renewable electricity by 2050 because all the other power plants will be taken off [line].

So I’m quite confident that it can be done, but it would require a major change in our infrastructure. The infrastructure here is the absolute key to this — we need to build an infrastructure that is different. But, again, our infrastructure in Europe is aging — we haven’t been building power lines since the ‘60s or ‘70s. It needs to be replaced anyway. So we need to make sure that the infrastructure is changed in a way that it accommodates 100 percent renewable electricity by 2050.
Interview with Christian Kjaer on steady growth of Wind Industry in Europe is excellent.
Wind Energy: A Vision for Europe in 2030 prepared by Advisory Council of the European Wind Energy Technology Platform, September 2006 has many interesting facts about Wind Energy Future in Europe. Here are some of them:
Twice the Turbines and Twelve Times the Power
And yet this does not mean covering Europe in
wind turbines. At the end of 2005, an estimated
47,000 wind turbines were installed in Europe. The average size of turbines delivered to the European market in 2004 was about 1.3 MW onshore and 2.1 MW offshore.

Under the assumption that by 2030 the average size of a wind turbine will be 2 MW onshore and 10 MW offshore, only 90,000 turbines (75,000 onshore and 15,000 offshore) would be needed to fulfil the 300 GW target. Almost no existing wind turbine will be operational in 2030, the technical lifetime for a turbine being twenty years onshore and twenty-five years offshore. In their place, integrated into the landscape, silent sentinels will gently spin – just twice the number of today, and yet generating twelve times as much power. The industry is optimistic about the potential for wind energy, more than it has ever been. Past targets set by the industry, and indeed by the European Commission in its 1997 White Paper on Renewable Energy, have been successively surpassed and upgraded.

Reliable, clean power for European domestic consumers and reduced power costs for increasingly high energy use industries can be obtained, and more cheaply than today. Energy is fundamental to any economy; wind energy can be a driver for European growth. With the right kind of collaboration and investment, electricity production from wind and its contribution to meeting European electricity consumption could raise from 83 TWh in 2005 to 965 TWh by 2030, supplying 23% of European electricity. This projection takes into account that consumption is expected to increase by half over the same period.

The size of commercially available grid connected horizontal axis wind turbines has evolved from about 0.022 MW in the early nineteen eighties to about 6 MW today. These larger machines are being developed principally, though not solely, through the drive to take the technology offshore. However, the notoriety of “big-wind” technology should not be allowed to eclipse the fact that other paths continue to be developed, from the smaller 600 kW, off-grid application turbines, right down to turbines of just a few kilowatts or less, which can provide essential power for isolated communities, lighting for individual homes and power for schools and hospitals, not least in many developing countries where electricity is still not part of everyday life for many citizens.
Many different design concepts are in use, the
most common among larger turbines being three bladed, pitch regulated, horizontal axis machines. As “big wind” has grown larger and larger, the way in which important design parameters have changed with size can be used to predict how turbines may develop in the future. For various design parameters these trends can be used to establish key challenges for the industry.
Going Offshore

Currently, offshore installations only constitute a
very small part of the market, but their future looks bright and therefore constitutes the main driver for large turbine technology development.
The existence of energy interests already offshore does not mean that offshore wind technology is just an “add-on” – far from it. Although a mature European offshore industry exists in the context of oil and gas recovery, the demands of offshore wind farms are quite specific and ongoing development is expected in the areas of foundations, access, windfarm electrics, transportation and erection. In the oil and gas industry, maintaining production is of overriding importance and justifies high capital cost solutions. In the wind industry, production is also vital, but so also is minimisation of capital costs. Oil rigs are massive one-off constructions whereas a large offshore wind farm may have hundreds of turbine units. So while the existing offshore industry possesses knowledge and experience of considerable value to the wind industry, it can not provide “off-the-shelf” equipment that is optimum for wind farm establishment".
Dr.A.Jagadeesh Nellore (AP), India
Wind Energy Expert
Posted by Dr.A.Jagadeesh on 10 Sep 2010

12 JUL 2010: REPORT
With a Boost from Innovation,Small Wind Is Powering Ahead
New technologies, feed-in tariffs, and tax credits are helping propel the small wind industry, especially in the United States. Once found mostly in rural areas, small wind installations are now starting to pop up on urban rooftops.

The Solarium, a new 8-story apartment building in New York City, is part of a new wave of green buildings in Gotham. Its exterior is made from 100 percent recycled material. The burnished floors are sustainably farmed bamboo. The apartments lack bathtubs in order to save water. Perhaps the most novel green accoutrement of the Solarium, however, is a small, black windmill perched on a short pole rising from the rooftop. Made by WindTronics, the windmill went live in April — it is one of the early beta units from the Michigan startup.

The company claims a single windmill can supply as much as 30 percent of a household’s annual power needs if winds average roughly 10 miles per hour. That is a brisk steady breeze but even homes averaging lesser amounts (5-9 mph winds) can receive significant electrical outputs of 15 to 30 percent of annual power needs. The Solarium’s wind turbine will power light fixtures in common areas and a rooftop theater for residents. “It has no noise and no vibration,” says Cyrus Claffey, the CEO of Clareo Networks, a real estate technology and design company that researched and planned the project for the Solarium’s developers. “It is bird friendly. And it has a great design. Power kicks in at a much lower windspeed than comparable products.”

The gearless WindTronics system generates energy at the blades’ tips and can be installed on a rooftop.
This WindTronics windmill represents a new wave of technology innovation sweeping through the small wind industry. This innovation combined with national, regional and local incentives, as well as significant cost reductions in installations and products, is driving fast growth for small windmill makers. In 2009, despite an abysmal economy, the U.S. small wind market (turbines with rated capacities of 100 kilowatts or fewer) grew by 15 percent, according to the American Wind Energy Association (AWEA). That growth included an increase of 20.3 megawatts of new capacity and $82.4 million in sales.

The 2009 tally pushed the total installed capacity of small wind turbines in the United States to 100.2 megawatts. (That’s only equivalent to one-fifth the output of an average coal-fired power plant in the United States. But more than half of that capacity came online in only the last three years, making small wind one of the fastest-growing renewable energy resources around.) This adoption is being driven by government incentives, improved zoning procedures, consumers’ growing affinity for residential clean energy, and emerging financing mechanisms. The 2009 American Recovery and Reinvestment Act expanded available federal investment tax credits for small windmills to 30 percent of the total cost of a wind system, an enormous boost that puts small wind on equal footing with the fast-growing residential solar industry.

“You can add the federal credit on top of state level rebates that can be 20 percent to 25 percent and that pushes the effective price of installing a small residential wind system down to $15,000 on average,” says Ron Stimmel, the legislative affairs manager for AWEA. With such a system, he notes, consumers are effectively pre-paying their electricity bills for decades. According to Stimmel, most windmills have a lifespan of 20 to 30 years.
To date, most of the growth in small wind in the United States has come in rural and semi-rural areas. This has been due to the requirement for many types of small windmills to sit atop poles that rise at least 40 feet above
To date, most of the growth in small wind in the U.S. has come in rural or semi-rural areas.
terra firma. Rural areas have long been more permissive of these types of installations. Looser zoning codes in those areas have allowed farmers to put up windmills without having to go through permitting hoops — or angering neighbors who might have to look at the spinning systems. Even in these types of rural regions, however, penetration remains below 5 percent and room for growth is enormous.

Some rural states have embraced wind at a policy level. Vermont, for example, became the first state to implement a feed-in tariff (FIT) for small wind systems. This tariff guarantees that small wind farmers can resell excess power back to the big utilities at above market rates.

According to AWEA, roughly half of all small wind power additions in 2009 were in the U.S., and the country has more than three times as many small wind manufacturing companies as the next closest competitor, Japan. While the U.S. may lead in small wind innovation, the rest of the world is looking to catch up. Japan, Canada, the United Kingdom, China, Germany and Holland all have significant numbers of small wind technology companies.

At present, the United Kingdom and Canada have the most well-developed small wind markets outside of the United States. But 33 countries have put in place FITs for small wind power generated by homeowners and small busineses who wish to sell their power back into the grid. Such tariffs are designed to promote the installation of smaller scale renewable power projects. These countries include most of the developed world and emerging giants such as China and India, but also a number of developing economies including the Philippines and Kenya. International policy and finance bodies are pushing hard to bring small wind systems to isolated rural communities, particularly as a complement to solar installations. The World Bank has undertaken an aggressive program to push small wind to developing nations in South America, Asia and Africa as part of its Renewable Energy in the Rural Market initiative.

Many existing small wind companies have global dealer networks, and renewable energy project finance is now finally catching up, allowing dealers both in the U.S. and abroad to offer buyers financing options to defray costs or maximize tax benefits. “The primary step is going to be distributor financing,” says J.J. Carrasco, a principal at Atoll Financial,
Thirty-three countries have put in place feed-in tariffs for small wind power from homeowners and businesses.
which signed a deal in 2009 to underwrite purchases of small wind turbines sold by Helix Wind. While Atoll plans to launch its projects in the U.S., “We are also interested in bringing U.S. energy applications in developing markets such as China and Brazil,” says Carrasco. Other investors and financiers, like Carrasco, have taken a keen interest in small wind. Over the past five years, venture and private equity investors have poured $252 million into U.S. small wind companies, hoping to reap substantial rewards as the market lights up and more homes, commercial buildings and farms turn to spinning blades to lighten their electric bills.

In the U.S., Stimmel and other industry experts believe farmers and others in out-of-the-way tracts will continue to put up tall poles and windmills at increasing rates, effectively hedging themselves against often volatile electricity prices. But smaller windmills are moving closer to the city centers in less dense metropolitan areas and are popping up like mushrooms in exurbs on smaller plots of land of less than an acre.

Take the case of Nancy Tabor. The co-owner of McClane Electric, a small alternative energy contracting firm located near Las Vegas, Nev., Tabor signed up as a dealer for Arizona-based Southwest Windpower in January, 2009, after the new federal tax credit for small wind became law. In the wake of the credits, Southwest Windpower secured a financing vehicle for its dealers, allowing homeowners to more easily borrow money to pay for wind turbine installations.

Several years earlier, the city of Las Vegas had passed new permitting procedures that made it much simpler for homeowners in some areas to
A Hawaii company seeks to produce wind power by capturing flutter and vibration in a stretched membrane.
receive approval for wind turbines on plots of land as small as a half-acre. Tabor has installed several units and says many more customers are eager to put up a windmill, pending the requisite collection of wind data for their proposed sites. “Out here, you have really good winds in many places, particularly with a little bit of elevation. It’s an excellent place for these types of projects,” says Tabor.

The arrival of more advanced systems, like the WindTronics device, could herald deeper penetration into urban areas previously considered unusable due to the chaotic nature of the breezes and the long periods of relative low winds. The WindTronics system, which resembles a fancy racing bike wheel, is vibration- and noise-free. Birds readily recognize the windmill, and it can be installed on a rooftop, eliminating the need for tall, unsightly poles. More importantly, according to WindTronics, it begins to generate power at wind speeds as low as two miles per hour, five miles per hour less than more traditional windmill designs, and it can continue to generate power at wind speeds as high as 42 miles per hour, nearly 15 miles per hour higher than standard shut-off speeds for most wind turbines.
Natural Gas as Panacea:
Dubious Path to a Green Future
Many energy experts contend natural gas is the ideal fuel as the world makes the transition to renewable energy. But since much of that gas will come from underground shale, ecologist Daniel B. Botkin writes, potentially at high environmental cost, it would be far better to skip the natural gas phase and move straight to massive deployment of solar and wind power.
WindTronics is hardly alone in trying to reinvent the small wind turbine. Hundreds of startups and incumbents right now are vying for traction in the nascent market. The vast majority of these small wind players are located in the U.S., making the country the capital of small wind innovation. Systems either proposed or in production range from very standard four- and three-blade systems, to bicycle-wheel designs like that of WindTronics, to vertical-axis windmills that catch wind power in spiraling motions. A novel wind-power startup based in Hawaii, Humdinger Wind Energy, seeks to produce wind power by capturing flutter and vibration in a stretched membrane, a method akin to capturing the energy produced by the snapping of a flag in the breeze.

This upswelling of innovation bodes well for the future of small wind and could help bring a wind-driven glow to many more homes and buildings in the not so distant future.

I entirely agree with you Mr.Alex Salkever.
In a very interesting article, The Future of Personal Wind Turbines,Environmental Graffita, GetFacts not Hype brought out lucid analysis of small wind turbines and their future:
“Green energy for the environment is a hot topic today, and now it’s becoming even more a reality for the USA, UK and for Canada. Small wind turbines for homes and small businesses are finally here, and they take on a smaller form than their predecessors, for they can be easily mounted on a rooftop or pole. They also can be tied to the national grid system, thereby selling any excess back to the electric company.

In past years, wind turbines and wind farms were used more by India and Germany, but recent results show that the United States has taken over the top spot. The United Kingdom is seated at a respectable number 5 as a country having the most functioning wind turbines. But typically countries have had such devices on farms, on the plains, near mines, offshore and other places with wide open spaces. That is changing. A good part of its location use was due to the fact that the turbines were very large, disrupting the landscape, and causing local opposition, and that too is changing.

In the past, wind turbines have been primarily Horizontal Axis Wind Turbines (HAWTs), or Vertical Axis Wind Turbines (VAWTs) that came with a host of challenging problems. HAWTs were difficult to install and transport and approximately 20% of the transportation cost was added to the equipment cost.

VAWTs did not fair much better, for they had blade failure due to fatigue and changing parts could be difficult depending on the design of the VAWT. One VAWT subtype generally required some external power source because the starting torque was so low. Moreover, both the HAWTs and VAWTs required additional expensive equipment. HAWTs needed an additional yaw control mechanism to turn blades and nacelle toward the wind, and filtering was needed to suppress signal clutter of radar installations, because the reflection of the tall towers could affect side lobes there. VAWTs had additional structures or parts so that downward thrusts that cause stress could be eliminated. These units along with other subtypes such as the helical twisted VAWTs and those with rotating sails are still used and will not be completely in our past, but they will not be the only wind source available in the near future. Small wind turbines for residential use and small business use can help supplement home and business owners thanks to emerging new technologies.

Designers have been hard at work to create a less obtrusively visible turbine that has a 20-year life span, usually a 5 year warranty and is not as cost prohibitive as its former cousins.

Some small-scale, home-based turbines are already being used - BBC News reported in Oct 2005 that 7,000 turbines were already in use based on households that had been given grants and paid for 1/3 of the total cost. The source noted that the typical household saw a reduction between a quarter and a third of its annual bill and that some places in the UK could benefit more depending on the location and if it was more particularly windy”.

Andrew Nusca is very optimistic about small wind turbine market, Small wind turbine market to double by 2013, study says, (smartplanet Dec 10, 2009):

“Individuals and businesses around the world have shown growing interest in small wind turbines to provide green energy, according to a new report.
A niche industry, the small wind turbine market saw $203 million in revenue in 2009, and is expected to grow to $412 million by 2013, according to Pike Research’s Small Wind Power report, released Wednesday.
On a cost-per-watt basis, small wind turbines can be less expensive than solar panels, according to the report, written by senior analyst David Link. That fact is especially true in the United States and United Kingdom, where government incentives and tax credits make the market more favorable than in years past.
Put the WIND to Work: To get inexhaustible, pollution-free energy which cannot be misused.
Dr.A.Jagadeesh Nellore (AP), India
Wind Energy Expert
Posted by Dr.A.Jagadeesh on 11 Sep 2010
02 Aug 2010: Report
Are Cell Phones Safe?
The Verdict is Still Out
While some studies have suggested that frequent use of cell phones causes increased risk of brain and mouth cancers, others have found no such links. But since cell phones are relatively new and brain cancers grow slowly, many experts are now recommending taking steps to reduce exposure.

Does your cell phone increase your risk of brain cancer? Does it affect your skin or your sperm viability? Is it safe for pregnant women or children? Should you keep it in your bag, on your belt, in your pants or shirt pocket? Should you use a hands-free headset? Are present cell phone safety standards strict enough?

You don’t know? You’re not alone.

With some 4 to 5 billion cell phones now in use worldwide and hundreds of studies seeking evidence of their health effects published in peer-reviewed journals over the last 10 years, there’s precious little scientific certainty over whether cell phones pose any danger to those using them. For nearly every study that reports an effect, another, just as carefully conducted, finds none. All of which leaves journalists, consumer advocates, regulatory agencies, politicians, industry spokespersons, and cell phone users able to choose and interpret the results they prefer, or ignore the ones they don’t.

Getty Images

There are some 4 to 5 billion cell phones now in use worldwide.
Do you, for instance, cite the studies that report adverse effects on sperm viability and motility, due to exposure to cell phone radiation or the studies that showed no — or mixed — results?

Do you cite the 2001 study that found increased incidence of uveal melanoma (a cancer of the eye) among frequent cell phone users, or the 2009 study by the same authors that, in reassessing their data, found no increase?

Do you cite the Israeli study that found an association between salivary gland cancer and heavy use of cell phones or the Swedish study that found none?

Do you parse the data and report only those results that have found effects — no matter how small — without citing studies that found no effects? In its much-cited review of cell phone studies, the Environmental Working Group has done just that, reporting, for instance, that “a study from the University of California, Los Angeles, found a correlation between prenatal exposure to cell phone radiation and behavioral problems in children.” But the group left out the study’s very next sentence acknowledging that the association may be “noncausal and may be due to unmeasured confounding.”

The effects of cell phones have proven difficult to assess because they are relatively new, the way and the amount they’re used continues to evolve, and the problems that cell phones might cause are hard to detect. Brain cancers, for instance, are very rare cancers. They affect only some 18 out of every 100,000 people. But the fact that there’s been no recent increase in the numbers may be meaningless with regard to cell phone use since brain cancers are very slow-growing.

Cell phones produce “non-ionizing” radiation, which, unlike X- or gamma rays, doesn’t damage DNA by stripping away electrons from molecules in cell tissue. Radiofrequency energy does, however, produce heat and, at high enough levels, can damage cell tissue. This, in the late 1990s,
The question is whether safety standards are sufficient to protect against long-term exposure.
prompted the U.S. Federal Communications Commission (FCC) and the International Commission on Non-Ionizing Radiation Protection (ICNIRP) in Europe to set limits on cell phones’ Specific Absorption Rate (SAR) — the measure of the amount of radiofrequency energy a cell phone user absorbs — at, respectively, 1.6 and 2.0 watts per kilogram. The question remains, however, whether these standards are sufficient to protect against long-term exposures and whether the buildup of heat in cell tissues is more damaging where there’s less blood flow to dissipate it, such as the outer ear, brain, skin, or testes.

The exposure standard has been the subject of Congressional hearings. Consumer groups have warned that children may be more susceptible to radiofrequency heating effects than adults. U.S. Congressman Dennis Kucinich introduced a bill for a federal research program on the effects of cell phone radiation that also calls for a label warning users about potential links between long-term use and cancer.

Last month, San Francisco passed a “Cell Phone Right-to-Know” law that requires manufacturers to post in stores each cell phone’s Specific Absorption Rate. In response, CTIA-The Wireless Association, which represents the wireless communications industry, filed suit July 23 in U.S. District Court in San Francisco to block enforcement of the new law. It cites the U.S. Food and Drug Administration’s (FDA) statement that “the weight of scientific evidence has not linked cell phones with any health problems.”

So far, the National Cancer Institute stands by the FDA. And neither the FCC nor the ICNIRP has recommended any changes in their present standards until there’s clear scientific evidence to demonstrate they need changing.

That kind of clarity may be a long way off.

Take, for example, the findings released in May of INTERPHONE, the largest and longest study ever conducted on whether — and by how much — cell phone use increases the odds of developing brain cancer. Carried out by the International Agency for Research on Cancer — at a cost of some $25 million and nearly 10 years in the making — the study involved roughly two dozen scientists and research teams from around the world and some 10,000 patients and cell phone users from 13 countries. The study’s epic scope, however, only made its meager conclusions seem all the more unsatisfying.

“Overall, no increase in risk of glioma [a cancer of the cells that protects the brain’s neurons] or meningioma [tumors that develop in the tissue that surrounds the brain] was observed with use of mobile phones,” the study concluded. “The possible effects of long-term heavy use of mobile phones require further investigation.”

And yet even these modest claims proved contentious. The study scientists themselves recognized problems in the methodology: While they had good data on the participants’ tumor and cancer histories, they had very suspect
‘After 10 years of research, we do not have an answer whether mobile phone radiation causes brain cancer,’ says one expert.
data on their cell phone usage. Participants’ recall of how often and how much they talked on their cell phones, when checked against their actual cell phone records, in some cases proved very unreliable. The matching of patients with control subjects also turned out to be problematic. Should controls include only those who never used a cell phone and exclude those who’d used one only infrequently? While the distinction may seem insignificant, such selection biases can wreak statistical havoc. The analysis using the first group, for instance, resulted in the somewhat astonishing finding that regular users of cell phones had a reduced risk of developing glioma.

No one was surprised, therefore, that divisions appeared over interpreting the study’s results. These delayed its release for four years. The raw data, in fact, showed that “long-term heavy use” — that is, talking on a cell phone for 30 minutes a day for 10 years — increased the odds of developing glioma by 40 percent. The question was whether this result was subject to the same selection bias as that which strangely showed a reduced risk among regular users. The final decision was that the findings with regard to the “effects of long-term heavy use” were, while worth “further investigation,” too unreliable to conclude they represented a clear and irrefutable increased risk.

While the risk of any individual developing glioma would still be small, a 40 percent increase could still mean some thousands more new cases in the U.S. each year. And gliomas account for nearly half of all childhood tumors.

The question for the INTERPHONE scientists was whether this finding was real or the result of flawed data?

As Finnish researcher Dariusz Leszczynski of Helsinki’s STUK-Radiation and Nuclear Safety Authority, put it, the study’s combination of reliable and flawed information resulted in a “scientifically unreliable and non-informative result.”

“What it all means,” Leszczynski concludes, “is that after 10 years of research and millions of Euros used for it we are still in the starting point [his emphasis] and do not have the answer whether, or whether not, mobile phone radiation could cause brain cancer.”

Christopher Wild, director of the International Agency for Research on Cancer, acknowledges that most of the study’s participants, even the heaviest users, were not frequent mobile phone users by today’s standards. The criteria for a “regular” user was someone who made from one call a week to 25 calls a day, but no one in the study talked for more than half an hour a day. On the other hand, the study doesn’t take into account that people now often text rather than talk, and many more use hands-free headsets.

Ten years of use may not be a legitimate time frame to establish any causal links to such slow-growing cancers. And if there is a risk, does it continue to increase beyond 10 years of usage, and by how much? This would especially be a concern for those who began using cell phones when they were children, as is now frequently the case.

New epidemiological studies now underway might prove more elucidating. They include COSMOS, a United Kingdom study that will follow for 20 to
Nearly everyone seems to agree that it’s worth reducing your exposure as best you can.
30 years some 350,000 cell phone users from the UK, Finland, Sweden, Denmark, and The Netherlands, and that will use actual cell phone records for their database. Another study, MOBI-KIDS, is a European Union project in 13 countries that over five years will compare the cell phone usage of some 2000 young people, ages 10 to 24, with brain tumors to the same number of healthy controls.

Are there alternatives to epidemiological studies?

Studying animals exposed to cell phone radiation has proven difficult, especially when it comes to controlling doses of radiation which, in the case of cell phones, are small; the response of animal cells at low doses may not reflect the response of human cells.

Recent in vitro studies — that is, studies on cultured cell tissue — have focused on whether radiofrequency radiation might interfere with the DNA repair process and cause damaged DNA to accumulate. So far, some studies have found damage while others have not. With so much uncertainty as to what exactly causes the disruption of cell processes, it’s difficult to compare one study with another. The same uncertainty has been true regarding the few studies on sperm — of concern because many men tend to keep their cell phones in their front pants pockets.

Leszczynski and others point out that present SAR standards don’t necessarily take into account how cell phones are actually used. While our brain may be exposed to the allowable amount of radiofrequency radiation, our bodies and our skin may be getting more than the phone’s advertised dose of radiofrequency radiation. A hands-free device can reduce exposure to the head, but if you still keep your phone in your shirt pocket, your body’s still being exposed.

In the meantime, nearly everyone seems to agree that it’s worth putting the precautionary principle into play; that is, reduce your exposure as best you can. The radiofrequency radiation falls off quickly the farther your cell phone is from your body. Look for a cell phone with a low SAR. Don’t keep your cell phone in your pocket. Use a hands-free device. Text rather than talk. And while the cancer risks are unknown, the risks from using your cell phone while driving are pretty clear.


There is a long debate on usage of cell phone and health risk.
In an interesting article, How Safe are Cell Phones?
Research indicates long-term cell phone use may pose health risks, Guide
Larry West wrote:
“Do Cell Phones Cause Cancer?
Wireless cell phones transmit signals via radio frequency (RF), the same kind of low-frequency radiation used in microwave ovens and AM/FM radios. Scientists have known for years that large doses of high-frequency radiation—the kind used in X-rays—causes cancer, but less is understood about the risks of low-frequency radiation.
Studies on the health risks of cell-phone use have produced mixed results, but scientists and medical experts warn that people should not assume no risk exists. Cell phones have been widely available for only the past 10 years or so, but tumors may take twice that long to develop.
Because cell phones haven’t been around very long, scientists haven’t been able to assess the effects of long-term cell-phone use, or to study the effects of low-frequency radiation on growing children. Most studies have focused on people who have been using cell phones for three to five years, but some studies have indicated that using a cell phone an hour a day for 10 years or more can significantly increase the risk of developing a rare brain tumor.
What Makes Cell Phones Potentially Dangerous?
Most RF from cell phones comes from the antenna, which sends signals to the nearest base station. The farther the cell phone is from the nearest base station, the more radiation it requires to send the signal and make the connection. As a result, scientists theorize that the health risks from cell-phone radiation would be greater for people who live and work where base stations are farther away or fewer in number—and research is beginning to support that theory.
In December 2007, Israeli researchers reported in the American Journal of Epidemiology that long-term cell-phone users who live in rural areas face a "consistently elevated risk" of developing tumors in the parotid gland compared with users who live in urban or suburban locations. The parotid gland is a salivary gland located just below a person’s ear.
And in January 2008, the French Health Ministry issued a warning against excessive cell phone use, especially by children, despite the lack of conclusive scientific evidence linking cell-phone use with cancer or other serious health effects. In a public statement, the ministry said: "As the hypothesis of a risk cannot be entirely excluded, precaution is justified."
Dr.A.Jagadeesh Nellore (AP), India

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