Hydrogen Economy - A Revolutionary Vision for the Future of Energy
2.4.03 Darshan Goswami, Project Manager, U.S. Department of Energy
INTRODUCTION
A new day is dawning for a revolutionary way to generate electric power from renewable energy sources. Visualize a future where the electrical power needed to run your computer, television, VCR and DVD is generated from a small appliance (about the size of a dishwasher) located in your home. Imagine that you will probably never experience a power outage. Envision generating electricity without combustion, and producing heat and pure drinking water as by-products. Picture a world powered almost entirely by an infinitely abundant and totally clean fuel. Hydrogen, the most common element in the universe, is that fuel. It can be produced from tap water and used to generate power for homes, industry and cars. Imagine a world energy economy based on hydrogen, and a society transformed by the hydrogen revolution. Imagine being able to drive your car more than 5,000 miles between fill-ups. In the new Hydrogen Economy, your car could become a “power station on wheels” producing about 20 to 40 kilowatts of electricity. Imagine that, while you are at work and your car is in the parking lot, it could be making money for you by supplying energy to the power grid during peak hours when demand for electricity is greatest. While in your garage the same fuel cells in the car could supply power for your home. This affords an ideal opportunity for car owners to become their own energy suppliers, and sell the excess power generated by the car’s fuel cells while it is parked. Automobile, oil, utility, and other major companies are spending billions to make this dream come true.
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Hydrogen is the future fuel. Along with fuel cells, hydrogen offers a reliable carrier.
Early developments of Hydrogen cars:
Since 1993, the prophets of the hydrogen economy have declared again and again that the technology already exists. Which left consumers to wonder, where’s the car and why am I still pumping unleaded? Well, the world can stop wondering. After 13 years of teasing announcements and endless talk, the era of the hydrogen fuel cell has finally arrived … sort of. Well, not exactly, but almost. Contrary to popular misconception, hydrogen fuel cells are not a new technology. In 1889, chemists Ludwig Mond and Charles Langer built the first device using oxygen and coal gas to produce power and water through a chemical reaction. But fuel cells were weak and fragile and complicated to make, and by the end of the 1800s it was clear that the internal combustion engine – that gas-chugging, smoke-belching scourge – was set to revolutionize every industry in the world. Marc Melaina, a professor at the University of California, Davis, has spent much of his academic career studying the economics of hydrogen transportation. The bottom line: it’s expensive but not impossible. “The fact that they’ve made improvements in vehicle performance is critical, but cost [reductions] also have to be realized and that can only happen through mass production,” he says. “So stations have to be put down for consumer convenience, then mass production of vehicles can ramp up, but the two basically have to happen at the same time for the economics to pay off.” That, he says, is going to require investment from automakers, energy companies and government, all working in partnership, all taking a bit of a leap of faith that hydrogen really is the best bet for the future. The car works which itself is a great achievement.
The hydrogen economy is a proposed system of delivering energy using hydrogen. The term hydrogen economy was coined by John Bockris during a talk he gave in 1970 at General Motors (GM) Technical Center.
Hydrogen advocates promote hydrogen as a potential fuel for motive power (including cars and boats), the energy needs of buildings and portable electronics. Free hydrogen does not occur naturally in quantity, but can be generated by steam reformation of hydrocarbons, water electrolysis or by other methods. Hydrogen is thus an energy carrier (like a battery), not a primary energy source (like coal). The feasibility of a hydrogen economy depends on issues of electrolysis, energy sourcing, including fossil fuel use, climate change, and sustainable energy generation.
A hydrogen economy is proposed to solve some of the negative effects of using hydrocarbon fuels where the carbon is released to the atmosphere. Modern interest in the hydrogen economy can generally be traced to a 1970 technical report by Lawrence W. Jones of the University of Michigan.
In the current hydrocarbon economy, transportation is fueled primarily by petroleum. Burning of hydrocarbon fuels emits carbon dioxide and other pollutants. The supply of economically usable hydrocarbon resources in the world is limited, and the demand for hydrocarbon fuels is increasing, particularly in China, India, and other developing countries.
Proponents of a world-scale hydrogen economy argue that hydrogen can be an environmentally cleaner source of energy to end-users, particularly in transportation applications, without release of pollutants (such as particulate matter) or carbon dioxide at the point of end use. A 2004 analysis asserted that "most of the hydrogen supply chain pathways would release significantly less carbon dioxide into the atmosphere than would gasoline used in hybrid electric vehicles" and that significant reductions in carbon dioxide emissions would be possible if carbon capture or carbon sequestration methods were utilized at the site of energy or hydrogen production.
Hydrogen has a high energy density by weight. An Otto cycle internal-combustion engine running on hydrogen is said to have a maximum efficiency of about 38%, 8% higher than a gasoline internal-combustion engine.
The combination of the fuel cell and electric motor is 2-3 times more efficient than an internal-combustion engine. However, the high capital costs of fuel cells, about $5,500/kW in 2002, are one of the major obstacles of its development, meaning that the fuel cell is only technically, but not economically, more efficient than an internal-combustion engine.
Other technical obstacles include hydrogen storage issues and the purity requirement of hydrogen used in fuel cells – with current technology, an operating fuel cell requires the purity of hydrogen to be as high as 99.999%. On the other hand, hydrogen engine conversion technology is more economical than fuel cells.
If energy for hydrogen production were available (from wind, solar, fission or fusion nuclear power etc.), use of the substance for hydrocarbon synfuel production could expand captive use of hydrogen by a factor of 5 to 10. Present U.S. use of hydrogen for hydro cracking is roughly 4 million metric tons per year (4 MMT/yr). It is estimated that 37.7 MMT/yr of hydrogen would be sufficient to convert enough domestic coal to liquid fuels to end U.S. dependence on foreign oil importation, and less than half this figure to end dependence on Middle East oil. Coal liquefaction would present significantly worse emissions of carbon dioxide than does the current system of burning fossil petroleum, but it would eliminate the political and economic vulnerabilities inherent in oil importation.
Currently, global hydrogen production is 48% from natural gas, 30% from oil, and 18% from coal; water electrolysis accounts for only 4%. The distribution of production reflects the effects of thermodynamic constraints on economic choices: of the four methods for obtaining hydrogen, partial combustion of natural gas in a NGCC (natural gas combined cycle) power plant offers the most efficient chemical pathway and the greatest off-take of usable heat energy.
Biological production:
Fermentative hydrogen production is the fermentative conversion of organic substrate to biohydrogen manifested by a diverse group bacteria using multi enzyme systems involving three steps similar to anaerobic conversion. Dark fermentation reactions do not require light energy, so they are capable of constantly producing hydrogen from organic compounds throughout the day and night. Photo fermentation differs from dark fermentation because it only proceeds in the presence of light. For example photo-fermentation with Rhodobacter sphaeroides SH2C can be employed to convert small molecular fatty acids into hydrogen. Electro hydro genesis is used in microbial fuel cells where hydrogen is produced from organic matter (e.g. from sewage, or solid matter ) while 0.2 - 0.8 V is applied.
Biological hydrogen can be produced in an algae bioreactor. In the late 1990s it was discovered that if the algae is deprived of sulfur it will switch from the production of oxygen, i.e. normal photosynthesis, to the production of hydrogen.
Biological hydrogen can be produced in bioreactors that use feed stocks other than algae, the most common feedstock being waste streams. The process involves bacteria feeding on hydrocarbons and excreting hydrogen and CO2. The CO2 can be sequestered successfully by several methods, leaving hydrogen gas. A prototype hydrogen bioreactor using waste as a feedstock is in operation at Welch's grape juice factory in North East, Pennsylvania.
Biocatalysed electrolysis:
Besides regular electrolysis, electrolysis using microbes is another possibility. With biocatalysed electrolysis, hydrogen is generated after running through the microbial fuel cell and a variety of aquatic plants can be used. These include reed sweet grass, cord grass, rice, tomatoes, lupines, algae
Photoelectrochemical water splitting:
Using electricity produced by photovoltaic systems offers the cleanest way to produce hydrogen. Water is broken into hydrogen and oxygen by electrolysis—a photoelectrochemical cell (PEC) process which is also named artificial photosynthesis. William Ayers at Energy Conversion Devices demonstrated and patented the first multijunction high efficiency photoelectrochemical system for direct splitting of water in 1983.[32] This group demonstrated direct water splitting now referred to as an "artifical leaf" or "wireless solar water splitting" with a low cost thin film amorphous silicon multijunction sheet immersed directly in water. Hydrogen evolved on the front amorphous silcon surface decorated with various catalysts while oxygen evolved off the back metal substrate. A Nafion membrane above the multijunction cell provided a path for ion transport. Their patent also lists a variety of other semiconductor multijunction materials for the direct water splitting in addition to amorphous silicon and silicon germanium alloys. Research continues towards developing high-efficiency multi-junction cell technology at universities and the photovoltaic industry. If this process is assisted by photocatalysts suspended directly in water instead of using photovoltaic and an electrolytic system, the reaction is in just one step, which can improve efficiency.
Concentrating solar thermal:
Very high temperatures are required to dissociate water into hydrogen and oxygen. A catalyst is required to make the process operate at feasible temperatures. Heating the water can be achieved through the use of concentrating solar power. Hydrosol-2 is a 100-kilowatt pilot plant at the Plataforma Solar de AlmerÃa in Spain which uses sunlight to obtain the required 800 to 1,200 °C to heat water. Hydrosol II has been in operation since 2008. The design of this 100-kilowatt pilot plant is based on a modular concept. As a result, it may be possible that this technology could be readily scaled up to the megawatt range by multiplying the available reactor units and by connecting the plant to heliostat fields (fields of sun-tracking mirrors) of a suitable size.
Photoelectrocatalytic production:
A method studied by Thomas Nann and his team at the University of East Anglia consists of a gold electrode covered in layers of indium phosphide (InP) nanoparticles. They introduced an iron-sulfur complex into the layered arrangement, which when submerged in water and irradiated with light under a small electric current, produced hydrogen with an efficiency of 60%.
Thermochemical production:
There are more than 352 thermochemical cycles which can be used for water splitting, around a dozen of these cycles such as the iron oxide cycle, cerium(IV) oxide-cerium(III) oxide cycle, zinc zinc-oxide cycle, sulfur-iodine cycle, copper-chlorine cycle and hybrid sulfur cycle are under research and in testing phase to produce hydrogen and oxygen from water and heat without using electricity. These processes can be more efficient than high-temperature electrolysis, typical in the range from 35% - 49% LHV efficiency. Thermochemical production of hydrogen using chemical energy from coal or natural gas is generally not considered, because the direct chemical path is more efficient.
None of the thermochemical hydrogen production processes have been demonstrated at production levels, although several have been demonstrated in laboratories.
Other ways of Hydrogen Production:
Biosolar hydrogen production with green algae:
A fuel cell combines hydrogen and oxygen to produce electricity, heat, and water. In order to produce energy, fuel cells use oxygen and hydrogen. Hydrogen is high in energy, yet an engine that burns pure hydrogen produces almost no pollution. It’s also the most plentiful known element in the universe. Despite its simplicity and abundance, hydrogen doesn’t occur naturally as a gas on the Earth. However scientists have discovered how oxygen stops green algae from producing hydrogen. The findings could help those working towards “solar H2-farms” in which microorganisms produce hydrogen fuel from sunlight and water.
An international team of scientists from Oxford University and universities in Germany report their results in two papers, one in the journal JACS and one in PNAS, published this week. For years scientists have been interested in how we could, potentially, produce hydrogen from just sunlight and water to power vehicles and other devices. One option is to use photosynthetic microorganisms that are able to produce hydrogen as well as starch. Green algae are one of the microorganisms that many have suggested could be turned into living hydrogen factories. The team will shortly be publishing the results of similar research into nickel-iron hydrogenases, enzymes related to those that enable blue-green algae to produce hydrogen.
“The hydrogen-producing enzyme found in green algae, known as an iron-iron hydrogenase, has evolved a structure that makes it particularly susceptible to attacking oxygen molecules,” said Professor Fraser Armstrong from Oxford University’s Department of Chemistry, an author of both papers. “Because oxygen is a major by-product of the hydrogen-making photosynthetic process in such organisms, the build-up of oxygen, which rapidly attacks the active site of the enzyme, quickly brings the hydrogen-making process to an irreversible halt. Our work has revealed the mechanism of this process.”
Hydrogen and fuel cell combination will revolutionalise the energy revolution in transportation.
An affordable, portable, pocket-sized Personal Fuel Cell from Horizon’s:
The MiniPak uses a combination of Horizon’s mass-produced PEM fuel cells and a new low-cost metal hydride storage solution, which is able to store hydrogen safely as a dry, non-toxic and non-pressurized material. The fuel cartridge contains a metallic sponge that is able to absorb hydrogen and turn it into a solid hydride. It is then able to release it back to the fuel cell when needed. The PEM fuel cell combines oxygen from the air with the stored hydrogen - electricity via its USB port and trace amounts of water vapor.
Similar to a pocket-size distributed energy system, it avoids the energy losses that occur between the power plant and the battery operated devices that we charge from powerpoints. Cumulatively, these losses are massive. There are roughly 10,000 power plants in the US with an average thermal efficiency of 33%, and transmission losses of around 5-10%. When it comes to portable electronics, the US Environmental Protection Agency estimated that in 2004 in the US alone, there were 2.5 billion AC to DC power adapters consuming 207 billion kWh per year or up to 6% of the US$247 billion national electric bill. It is further estimated that 6 to 10 billion similar devices are presently in use worldwide, operating at an energy efficiency of around 50%. Whereas the MiniPak is not applicable to all AC to DC powered devices, it can indeed participate in reducing billions of dollars of wasted energy costs.
Besides contributing to overall efficiency, Horizon’s new micro-fuel cell system offers numerous environmental benefits. Just one of its Hydrostik fuel cartridges can deliver the same amount of power over its lifetime as over 1000 disposable alkaline AA batteries, while storing more energy at a lower cost. In addition, the cartridges do not contain any toxic materials and can be completely recycled, using conventional methods. “Over the past 4 years, Horizon has brought to market several award-winning products to retail environments in over 60 countries around the world. As these were primarily toys, few have realized the implications of these first products. They have in fact enabled Horizon to become the world’s largest volume producer of micro-fuel cells, and placed the company in a prime position to begin mass-commercialization into other new markets, including portable electronics. Our global market experience and mass-production are already in place, and with costs competitive to disposable batteries, Horizon’s refillable fuel cell products shift the paradigm”, noted Taras Wankewycz, Founder and Chief Marketing Officer.
The MiniPak is Horizon’s first portable fuel cell product to enter the market, while several others are currently under joint development with various large-scale global market leaders. Horizon is also scaling up the size of the solutions, since they offer the promise of storing renewable energy in larger quantities with no self-discharge and at a lower cost than batteries, therefore opening a path towards independent, distributed energy in homes, businesses and other industrial applications.
Hydrogen Energy Scene in India:
The National hydrogen energy road map (NHERM) is a program in Indiainitiated by the National hydrogen energy board (NHEB) in 2003 and approved in 2006 for bridging the technological gaps in different areas of hydrogen energy, including its production, storage, transportation and delivery, applications, safety, codes and standards and capacity building for the period up to 2020. The program is under direction of the Ministry of New and Renewable Energy (MNRE).
• Reduce India’s dependence on import of petroleum products.
• Promote the use of diverse,domestic,and sustainable new and renewable energy sources.
• Provide electricity to remote,far‐flung,rural and other electricity deficient areas.
• Promote use of hydrogen as a fuel for transport and power generation.
• Reduce carbon emissions from energy production and consumption.
• Increase reliability and efficiency of electricity generation.
• 1 Million Vehicles running on Hydrogen based IC Engines and fuel cells by 2020.
• 1000 MW electricity generation using fuel cells by 2020.
India has expertise and skills to develop hydrogen energy technologies, says UNIDO DG
Dr. K. Yumkella Director General of UNIDO visited the first fleet in the world of hydrogen fuelled rickshaws complete with a hydrogen refueling station. The fleet is operating since Monday 9 January, 2012 at the Pragati Maidan Exhibition ground in New Delhi.
During his visit, the UNIDO DG said: “This fleet and refueling infrastructure is proof that hydrogen has a role to play not only in the developed world but also in developing economies like India, not only for high-end vehicles and buses but also in down-to-earth practical applications like the rickshaws. This is proof that India has the expertise and skills to develop, implement and assess hydrogen energy technologies in view of its Hydrogen Roadmap and the 2020 Green Initiative for Future Transport. It is also evidence that the UNIDO International Centre for Hydrogen Energy Technologies in collaboration with UNIDO headquarters and UNIDO Regional Office can put flesh and bones in innovative energy concepts, in collaboration with local industry and academia. I am very pleased to visit this site and to see that the vehicles are used on a daily basis at the ITPO exhibition grounds, just like conventional vehicles, bar the zero emissions”.
The fleet of fifteen vehicles and the refueling station were established in the context of the DELHY-3W project that aimed to demonstrate hydrogen technologies developed by Indian partners for the Indian transport sector. The project took 3 years and cost slightly more than 1 million US$, with 0.5 million US$ of co-funding coming from the United Nations Industrial Development Organisation (UNIDO) International Centre for Hydrogen Energy Technologies (UNIDO-ICHET) based in Istanbul, Turkey, that also contributed in setting up and executing the project.
Project Consortium
IIT Delhi coordinated the project and provided technical expertise to convert the internal combustion engines to run on hydrogen. Mahindra and Mahindra developed the vehicle with all necessary changes to the engines, safety systems, fuel tanks and fuel lines. Air Products USA acted as project partner and sponsor by providing the hydrogen refueling station and management and technical services. UNIDO India regional office facilitated the realization of the project. India Trade Promotion Organisation (ITPO) is hosting the project and helping disseminate Indian know-how. The Indian Ministry of New and Renewable Energy (MNRE) has been closely following the project, while both the refueling facility & hydrogen storage tanks on vehicle have received all necessary permits and approvals from the Petroleum and Explosives Safety Organisation (PESO).
Institutes involved in Hydrogen energy:
Bharat Heavy Electricals Ltd. (R&D), Hyderabad. They are involved in the development of Phosphoric Acid Fuel Cells (PAFCs) and have developed a 50-kW stack. They have also installed a 200 kW fuel cell bases power plant. The fuel used is LPG and besides generation of electricity, it also produces hot water which is uses in their canteen.
TATA Energy Resources Institute (TERI) has in the past demonstrated the use of digester gas (biogas) for generating electricity from a 2.5-kW PAFC stack imported from ERC (Energy Research Corporation), USA.
MNES has funded the import of a 200-kW PAFC system made by the ONSI to evaluate its operation.
SPIC-SF (SPIC Science Foundation) is working on Proton Exchange Membrane (PEM) fuel cells and has developed stacks. They have also demonstrated a fuel-cell battery hybrid vehicle using a 10-kW PEM power plant.
Work on an MCFC stack is underway at TERI and the Central Electrochemical Research Institute. TERI has tested the operation of an MCFC monocell on simulated coal gas. Development of a kW-level stack is currently underway with the aim of integrating it with a coal gasifier.
Work on developing a DMFC (direct methanol fuel cell) is underway at IISc (Indian Institute of Science).
In addition, research on SOFC is being done at IISc and CGCRI (Central Glass and Ceramic Research Institute).
Research and development on metal hydride storage is ongoing at BHU (Banaras Hindu University).
Murugappa Chettiar Research Centre,Chennai:
Scientists around the world are developing a wide range of processes for producing hydrogen from water using expensive technologies. MCRC is the first one who attained the pre-commercial echelon in biological hydrogen production with an eco friendly genre after an epoch of intensive groundwork research activities over two decades by MCRC.
The idea of waste recycling (utilization) – is the most ideal alternative technology for removing pollutants from environment for bio-hydrogen generation, considered as an intriguing move toward future fuel for the next generation. Our primary focus is to develop a cost effective new technology to produce pure hydrogen from organic wastes viz., distillery, sago, and whey. Of the various wastes screened for BHP, distillery waste favoured both hetero and phototropic hydrogen producing bacterial strains of our own isolates. From our preliminary studies with bench scale, at this instant we have succeeded to pre commercial level (Treating 125 M3 distillery effluent / day) with sustained hydrogen production. Apart from energy, treatment of distillery waste also accomplishes a drastic reduction of COD and BOD upto 65 % and 90 % respectively within 48 h. Consequently, though the individual culture possesses the capability of hydrogen production, the cocktail of strains would ensure the complete exploitation of distillery waste with maximum hydrogen production. After production of hydrogen, due to the potential, the effluent can be subjected to composting, using which farmers would be benefited with concomitant profitability.
Tata motors is developing a electric and hybrid variant of Indica and ace. It has an agreement with Indian Space Research Organisation (ISRO). Tata Motors and Indian Space Research Organisation (ISRO) will develop hydrogen fuel cells for cars using ISRO’s cryogenic technology, as a spin-off of the cryogenic technology which was successfully developed for advanced launch vehicles
Hydrogen is high in energy content as it contains 120.7 kilojoules/gram. This is the highest energy content per unit mass among known fuels. However, its energy content per unit volume is rather low. Thus, challenges are greater in the storage of hydrogen for civilian applications, as compared to storage of liquid fossil fuels. When burnt, hydrogen produces water as a by-product and is therefore not only an efficient energy carrier but a clean, environmentally benign fuel as well. Hydrogen can be used for power generation and also for transport applications. It is possible to use hydrogen in internal combustion (IC) engines, directly or mixed with diesel and compressed natural gas (CNG) or hydrogen can also be used directly as a fuel in fuel cells to produce electricity. Hydrogen energy is often mentioned as a potential solution for several challenges that the global energy system is facing. The advantages are the fact that hydrogen use results in nearly zero emissions at end-use, and that hydrogen opens up the possibility of decentralized production on the basis of a variety of fuels.
Put HYDROGEN to WORK: To get inexhaustible,pollution-free energy which cannot be misused.
Acknowledgements: Some of the material taken from Wikipedia, gizmag and RobAid.
Dr.A.Jagadeesh Nellore(AP),India
E-mail: anumakonda.jagadeesh@gmail.com
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