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Showing posts with label Fuelcell. Show all posts
Showing posts with label Fuelcell. Show all posts

Thursday, April 27, 2017

Battery versus Hydrogen


The technology towards zero Carbon emissions from transportation has gained importance due to increasing air pollution from automobiles. It is not just the Carbon emission but oxides of Nitrogen and Sulphur, but also water vapour (more potent Greenhouse gas) to gather with particulate matters that compounds the emission problems. Current automobiles based on Internal combustion is not only energy inefficient but generates noise and air pollution. Therefore, battery cars and Hydrogen cars are increasing in popularity and competing with each other. We can examine the merits and demerits of these two technology for a better understanding. Transportation uses mechanical energy derived from thermal energy generated by combustion of fossil fuels but battery cars as well as hydrogen cars convert an electrochemical energy into mechanical energy. As we know energy can neither be created not destroyed but can be converted from one form to another form. The word “energy storage” is a misnomer because electrical energy is generated at the point of usage from stored chemicals by way of redox reactions. In both cases, we generate electrical energy from batteries or from Hydrogen through Fuel cell and then convert it into mechanical energy. Both battery as well as Fuel cell convert chemical energy into electrical energy by electro-chemical reaction namely redox reactions. For a redox reaction, we need both reduction (reductant) and oxidation (oxidant) reactions to take place simultaneously to effect flow of electrons from corresponding ions which we call electricity. It is clear from the above we need two reactants namely reductant and oxidant. In batteries both the reactant and oxidant are stored in solid form or in a liquid form in ‘flow batteries’. The chemistry of the redox reaction will determine the speed, size and the life of the battery. This creates a constraint on the size, weight and life of the battery to achieve a specific mileage. It means battery has a limitation when comes to size, life and mileage to be achieved. Tesla is currently leading the way in batteries both for stationery as well as transport applications. For stationery applications the space, weight and life may not be a big constraint but the life is a constraint and therefore the cost. But in transport applications all the above three parameters are critical and therefore battery may not be a long-term solution. In Hydrogen Cars Hydrogen gas is stored in a compressed form at high pressure in a cylinder. There is no Oxygen storage but only air is used as the Oxidant. Fuel cell uses both Hydrogen and Oxygen to generate electrical energy at the point of usage to run the motor. Electricity is not stored. The main difference between battery and fuel cell is, battery carries both Oxidant as well as reductant on board in solid form which weighs and occupies space; Fuel cell carries only Hydrogen as the reductant in gaseous form and not Oxidant. Hydrogen is a light weight and only the storage tank in the form of composite material is the actual weight. Moreover, there is more room to store Hydrogen like a Hydrogen bus which carries cylinders at the roof top. If we use renewable energy source such as solar and wind then Hydrogen generation and dispensing will not be a serious constraint for Hydrogen generation and distribution in the future. The biggest disadvantage with Fuel cell is the cost due to expensive catalyst such as Platinum. Each technology has its own advantages and disadvantages but the fundamental facts of these technologies will give us a glimpse of the future potential. In battery technology storing the reactants in solid form is an issue. Air metal battery has a good potential yet a long way to go. Similarly, if Hydrogen can be generated at the point of usage without storing Hydrogen on board that will open a greater potential. There may a hybrid solution in the future that can integrates both battery and Hydrogen- Fuel cell technologies will be the way forward. Research is being carried out to design a rechargeable Fuel cell battery with enhanced performance and cyclability. Such technologies will also guarantee a clean renewable energy storage technologies for stationery applications in the future. Hydrogen can be derived from many abundant natural sources such as seawater as I have explained in my previous article “CAPZ desalination technology uses only sun, sea and wind”.
Many people argue that Hydrogen is not an energy source but an energy carrier. Hydrogen is certainly an energy source by itself but is to be derived from other primary sources such as water or natural gas because Hydrogen is not available in a free form. Generation of Hydrogen from its sources require an additional energy but when such an energy is provided by renewable sources such as sun, wind and sea then the cost becomes secondary in the long run. Therefore, battery may not be able to compete with hydrogen in the long run though it provides a temporary solution to pressing power problems in short term. Moreover, batteries rely on materials like Lithium whose availability is limited even though they are recyclable.

Thursday, August 2, 2012

Solar Hydrogen for homes and cars.


Renewable Hydrogen offers the most potential energy source of the future for the following reasons. Hydrogen has the highest heat value compared to rest of the fossil fuels such as Diesel, petrol or butane. It does not emit any greenhouse gases on combustion. It can readily be generated from water using your roof mounted solar panels. The electrical efficiency of fuel cell using Hydrogen as a fuel is more than 55% compared to 35% with diesel or petrol engine. It is an ideal fuel that can be used for CHP applications. By properly designing a system for a home, one can generate power as well as use the waste heat to heat or air-condition your home. It offers complete independence from the grid and offers complete insulation from fluctuating oil and gas prices. By installing a renewable Hydrogen facility at your home, you can not only generate Electricity for your home but also fuel your Hydrogen car. The system can be easily automated so that it can take care of your complete power requirement as well as your fuel requirement for your Hydrogen car. Unlike Electric cars, you can fill two cylinders of a Hydrogen car which will give a mileage of 270miles.You can also charge your electric car with Fuel cell DC power. Renewable Hydrogen can address all the problems we are currently facing with fossil fuel using centralized power generation and distribution. It will not generate any noise or create any pollution to the environment. It does not require large amount of water. With increasing efficiency of solar panels coming into the market the cost of renewable Hydrogen power will become competitive to grid power. Unlike photovoltaic power, the excess solar power is stored in the form of Hydrogen and there is no need for deep cycle batteries and its maintenance and disposal. It is a one step solution for all the energy problems each one of us is facing. The only drawback with any renewable energy source is its intermittent nature and it can be easily addressed by building enough storage capacity for Hydrogen. Storing large amount of energy is easy compared to battery storage. The attached ‘You Tube’ video footages show how Solar Hydrogen can be used to power your home and fuel your Hydrogen car. Individual homes and business can be specifically designed based on their power and fuel requirements.

Monday, July 16, 2012

Hydrogen from seawater for Fuelcell


We have used Hydrocarbon as the source of fuel for our power generation and transportation since industrial revolution. It has resulted in increasing level of man-made Carbon into the atmosphere; and according to the scientists, the level of carbon has reached an unsustainable level and any further emission into the atmosphere will bring catastrophic consequences by way of climate change. We have already witnessed many natural disasters in a short of span of time. Though there is no direct link established between carbon level in the atmosphere and the global warming, there is certainly enough evidence towards increase in the frequency of natural disasters and increase in the global and ocean temeperatures.We have also seen that Hydrogen is a potential candidate as a source of future energy that can effectively substitute hydrocarbons such as Naphtha or Gasoline. However, hydrogen generation from water using electrolysis is energy intensive and the source of such energy can come only from a renewable source such as solar and wind. Another issue with electrolysis of water for Hydrogen generation is the quality of water used. The quality of water used for electrolysis is high, meeting ASTM Type I Deionized Water preferred, < 0.1 micro Siemen/cm (> 10 megOhm-cm). A unique desalination technology has been developed by an Australian company to generate onsite Hydrogen directly from seawater. In conventional seawater desalination technology using reverse osmosis process only 30-40% of fresh water is recovered as potable water with TDS less than 500 ppm as per WHO standard. The balance highly saline concentrate with TDS above 65,000 ppm is discharged back into the sea which is detrimental to the ocean’s marine life. More and more sweater desalination plants are set up all over the world to mitigate drinking water shortage. This conventional desalination is not only highly inefficient but also causes enormous damage to the marine environment. The technology developed by the above company will be able to recover almost 75% of fresh water from seawater and also able to convert the concentrate into Caustic soda lye with Hydrogen and Chlorine as by-products by electrolysis. The discharge into the sea is drastically reduced to less than 20% with no toxic chemicals. This technology has a potential to revolutionize the salt and caustic soda industries in the future. Caustic soda is a key raw material for a number of chemical industries including PVC.Conventionally, Caustic soda plants all over the world depends on solar salt for their production of Caustic soda.Hydrogne and Chlorine are by-products.Chlrine is used for the production of PVC (poly vinyl chloride) and Hydrogen is used as a fuel. In the newly developed technology, the seawater is not only purified from other contaminants such as Calcium, Magnesium and Sulfate ions present in the seawater but also concentrate the seawater almost to a saturation point so that it can be readily used to generate Hydrogen onsite. The process is very efficient and commercially attractive because it can recover four valuable products namely, drinking water, Caustic soda lye, Chlorine and Hydrogen. The generated Hydrogen can be used directly in a Fuel cell to generate power to run the electrolysis. This process is very ideal for Caustic soda plants that are currently located on seashore. This process can solve drinking water problems around the world because potable water becomes an industrial product. The concentrated seawater can also be converted in a salt by crystallization for food and pharmaceutical applications. There is a growing gap between supply and demand of salt production and most of the chemical industries are depending upon the salt from solar pans. Another potential advantage with this technology is to use wind power to desalinate the water. Both wind power and Hydrogen will form a clean energy mix. It is a win situation for both water industry and the environment as well as for the salt and chemical industries. In conventional salt production, thousands of hectares of land are used to produce few hundred tons of low quality salt with a year long production schedule. There is a mis- match between the demand for salt by large Caustic soda plants and supply from primitive methods of solar production by solar evaporation contaminating cultivable lands. The above case is an example of how clean energy technologies can change water, salt and chemical industries and also generate clean power economically, competing with centralized power plants fuelled with hydrocarbons. Innovative technologies can solve problems of water shortage, greenhouse gases, global warming, and environmental pollution not only economically but also environmental friendly manner. Industries involved in seawater desalination, salt production, chemical industries such as Caustic soda, Soda ash and PVC interested to learn more on this new technology can write directly to this blog address for further information.

Wednesday, June 6, 2012

Cheap Hydrogen to combat global warming?


Hydrogen is well-known as a potential source of clean energy of the future. But it is not available in a free form; its generation from water using Electrolysis requires more energy than, a free Hydrogen can generate. It requires about 5kws power to generate 1 m3 Hydrogen gas, which means, it requires about 56 Kw power to generate 1 Kg Hydrogen using water electrolysis. But 1Kg Hydrogen can generate only about 15-20 Kw Electricity using a Fuel cell. This anomalous situation makes Hydrogen generation using water electrolysis uneconomical for the purpose of clean power generation. That is why most of the Hydrogen is currently generated by steam reforming natural gas. Another reason for using natural gas is, to reduce the cost of Hydrogen and also, to achieve a smooth transition from fossil economy to Hydrogen economy using existing infrastructures. Power generation and transportation using Hydrogen and Fuel cell has been commercially tested, proven and ready for deployment. However, we still have to deal with emission of greenhouse gas during steam reformation of natural gas due to the presence of carbon atom in natural gas. Meanwhile, one American company recently announced a break-through technology that will generate free thermal energy from atomic Hydrogen using a patented process. The inventor of the process claims, when atomic Hydrogen is allowed to react with a specific Catalyst, Hydrogen atom undergoes a transition to a new atom called “Hydrino”, releasing energy while the electron in the atom shifts to a lower orbit close to proton. It was believed so far that the electron in Hydrogen atom is at its lowest level (ground level) and the closest to proton. This is the first time somebody claims that there is a lower state than the ground state in Hydrogen atom and the amount of energy released in this transition to ‘Hydrino”, is in between by an uncatalyzed Hydrogen atom by combustion and nuclear energy. Unlike nuclear energy, this energy is non-radioactive. But the energy released by this process is more than 200 times than energy released by Hydrogen atom by normal combustion. The reaction does not create any pollution or radio-active materials as by-products. The process has been tested, verified and certified by scientists in few laboratories and universities. The above process offers great hope to generate a clean, non-polluting energy at the lowest cost. The ‘dihydrino and Hydrogen is separated and Hydrogen is recycled back to continue the process while’dihydrino’ has other potential commercial applications. The inventor has named this power as “Black power” as he hypotheses that such phenomena explain the presence of “dark matter” in Galaxies. According to quantum mechanics, the energy level of a normal Hydrogen atom is at its ground level as its minimum level (N=1), but its energy level increases at higher states such as N=2, 3, 4.When the energy level jumps from higher (excited state) to a lower level, it emits energy in the form of photon of light (Quanta).The spectrum of such emission matches the ultraviolet light of the sun. Since sub-quantum atoms are non-radioactive, the inventor claims that he is duplicating the above process of Nature by a catalytic thermal process in the state of Plasma using a specific Catalyst. If such a large thermal energy is released by formation of ‘Hydrino’atom in the above process, then such energy can be used to generate Hydrogen by conventional water electrolysis at a fraction of the cost. Then, Hydrogen economy can become a commercial reality and the above technology has a potential not only to generate power at fraction of a cost of the fossil fuel but also to generate a clean and non-polluting power. The inventor has also hypothesised a "grand new unified theory” of atom as the basis for the above invention. Mainstream scientists have always have been reluctant to support such “free energy” theories but, when someone can demonstrate the process of generating an excess energy (more than 200 times than the theoretical energy released by an exothermic chemical reaction) and it is non-radioactive then mainstream scientists may be sidelined by world community. It is always possible to demonstrate something unique without any theory and come out later with a theoretical explanation to satisfy the scientific community. Many discoveries in the past were by mere accidents and one should have an open mind to look into any new concepts without any bias, especially if the discovery can resolve serious problems of humanity at times of crisis.

Monday, May 28, 2012

Fuelcell can become a commercial reality


We currently generate electric city from heat, obtained by combustion of fossil fuel such as coal, oil and gas. But such combustion generates not only heat but also greenhouse gases such as Carbon dioxide and oxides of Nirogen.The only alternative to generate power without any greenhouse gas emission is to use a fuel with zero carbon. However, oxides of Nitrogen will still be an issue as long as we use air for combustion because atmospheric air contains almost 79% Nitrogen and 21% oxygen. Therefore it becomes necessary to use an alternative fuel as well as an alternative power generation technology in the future to mitigate greenhouse problems. Hydrogen is an ideal fuel to mitigate greenhouse gases because combustion of Hydrogen with oxygen from air generates only water that is recyclable. Combining Hydrogen with Oxygen using Fuel cell, an electrochemical device is certainly an elegant solution to address greenhouse problems. But why Hydrogen and Fuel cell are not commonly available? Hydrogen is not available freely even though it is abundantly available in nature. It is available as a compound such as water (H2O) or Methane (CH4) and Ammonia (NH3). First we have to isolate Hydrogen from this compound as free Hydrogen and then store it under pressure. Hydrogen can easily form an explosive mixture with Oxygen and it requires careful handling. Moreover it is a very light gas and can easily escape. It has to be compressed and stored under high pressure. Generation of pure Hydrogen from water using Electrolysis requires more electricity that it can generate. However, Hydrogen cost can be reduced using renewable energy source such as solar thermal. The solar thermal can also supply thermal energy for decomposing Ammonia into Hydrogen and Nitrogen as well as to supply endothermic heat necessary for steam reformation of natural gas into Hydrogen. Onsite Hydrogen generation using solar thermal using either electricity or heat can currently become a commercial reality. Hydrogen generation at higher temperatures such as Ammonia decomposition or steam reformation can be directly used in Fuel cell such as Phosphoric acid Fuel cell. Phosphoric acid fuel cell is a proven and tested commercial Fuel cell that is currently used for base load power generation. It is also used for CHP applications. Hydrogen generation using solar thermal and power generation using Fuel cell is already a commercial reality and also an elegant solution to mitigate greenhouse gases. Large scale deployment of Fuel cell and solar thermal will also reduce the cost of installations and running cost competing with fossil fuel.Fuecell technology has a potential to become a common solution for both power generation and transportation. While Government can encourage renewable energy by subsidizing PV solar panels and discourage fossil fuel by imposing carbon tax, they should give preference and higher tariff for power purchase from Solar thermal and Fuel cell power generators. This will encourage large scale deployment of Fuel cell as a potential base load power source.

Wednesday, May 23, 2012

Liquid coal- a novel fuel to reduce greenhouse gas


Coal is the single largest fuel currently used for power generation all over the world due to its abundant availability and established infrastructure and technology. However greenhouse gas emission poses a significant challenge in continuing the usage of coal as prime fuel. Currently Natural gas is favored as fuel for power generation and number of LNG plants have been set up in many part s of the world. Coal seam methane gas is another potential source that competes with natural gas .Basically, Methane is the major constituent of such gases and they are suitable for both combustion as well as for gasification for power generation.Countries who are endowed with large deposits of coal such as Australia, South Africa, Indonesia have advantages in clean coal technologies and in reducing their greenhouse gas emissions. There is an opportunity for coal fired power plants to continue their operations if they can solve the greenhouse gas emission and other pollution problems associated with coal. Number of companies are now re-evaluating clean coal technologies such as IGCC and carbon capture and reuse. As we have seen in previous articles, Hydrogen is the key in developing clean coal technology of the future. That is why gasification technology such as IGCC (Integrated Gasification and Combined Cycle) is gaining importance over combustion technologies because, that is the only way we can introduce a Hydrogen molecule in the combustion by way of ‘Syngas’.By introducing Hydrogen, we not only improve the thermal efficiency but also utilize the heat of combustion to the maximum by combined cycle while reducing GHG emission. It also facilitates the usage of existing and known power generation technologies such as steam turbine and gas turbine as well as new technologies such as Fuel cell and Hydrogen turbines. Coal in the form of pumpable liquid (CWS –coal water slurry) is another key milestone in developing a clean coal technology. Countries like China and Indonesia have been using coal water slurry for power generation successfully. Finely powerdered coal is mixed with water in the ratio of 60:40 along with dispersant such as Lignosulfonate as additives to make a finely dispersed, viscous liquid that resembles heavy petroleum oil, ready for combustion. It is easier to handle pumpable oil than a solid coal. A novel products called ‘colloidal coal water’ (CCW) is a finely dispersed colloidal coal in water with additives such as surfactants and dispersants with specific formulating agents leading to certain rheological properties is a key development in clean coal technology. The coal water slurry currently used does not have long term stability and storage properties like colloidal coal water fuel. The work is under development and it is expected that such finely dispersed colloidal coal water mix resembling a liquid hydrocarbon may be named as ‘liquid coal’ for all practical purposes will become a low cost fuel in the future power generation. This ‘colloidal coal liquid’ can be easily gasified or used as liquid fuel for combustion equipments such as boilers and also serve as precursor for a number of chemical product synthesis as downstream products. The emitted Carbon dioxide can be captured cryogenically and separated in a pure form for potential application such as ‘Natural Refrigerant’ and to synthesize number of chemical products. Clean coal can become a commercial realty provided we re-evaluate the coal preparation, gasification methods and to contain emitted carbon into an useful product of commerce.

Thursday, May 17, 2012

Ammonia can substitute Gasoline


Ammonia is a well known industrial chemical that is manufactured worldwide as a precursor for the production of Urea. The chemistry and technology of Ammonia synthesis is well known and well established. It was a land mark achievement to fix atmospheric Nitrogen into the soil in the form of Urea as a fertilizer. It has 17.6% Hydrogen and 82.4% Nitrogen making it an ideal fuel for combustion when compared to Gasoline in terms of greenhouse gas emission because Ammonia no carbon. Handling free Hydrogen has always been a concern due to its explosive nature and lightness. Transportation of Hydrogen in the form of Ammonia is relatively cheaper and safer. A non-regulated Ammonia nursing tank at 265 psi pressure holds 3025kg Ammonia, containing 534kg Hydrogen, whereas a 5900 gallon Hydrogen tube trailer at 3200 psi pressure, contain only 350kgs of Hydrogen. Low pressure Ammonia tank with less than 25% volume contain more than 53% Hydrogen than a high pressure tube trailer. Ammonia has a lower volumetric energy density compared to other fuels.However, after subtracting energy required to elicit hydrogen from each fuel, hydrogen emerges with highest energy density compared to other fuels, and it is the only fuel which is carbon free. These qualities make Ammonia, a potential substitute for Gasoline. Ammonia need not be used as direct combustible fuel in internal combustion engines but it can be used as Hydrogen carrier safely and economically. The Hydrogen resulting from the decomposition of Ammonia can be used as fuel in a Fuel cell car as well as in a combustion engine. It can also be used to generate small onsite power using a Fuel cell or IC engine. For example, 534kg Hydrogen can generate Electricity up to 10 MW and up to 6Mw thermal energy using a Fuel cell. Currently ammonia is manufactured using fossil fuel source such as natural gas or naphtha to generate Hydrogen in the form of Syngas.But this can be effectively substituted with renewable source of Hydrogen such as Electrolysis of water using renewable solar thermal power or wind energy. Alternatively a biogas can be steam reformed to generate Hydrogen similar to natural gas. The generated Hydrogen can be compressed and stored. Nitrogen constitutes 79% of atmospheric air and it can be obtained by air liquefaction and separation by distillation or by simple membrane separation method to separate air into Nitrogen and Oxygen. The resulting Nitrogen can be compressed and stored for Ammonia sysnthsis.Production of Ammonia using Bosch Haber process is well known. Ammonia can be transported in pipelines, in tankers by road, rail or ship to various destinations. Ammonia can be readily be used as fuel using a spark ignited combustion engine with little modifications because Ammonia is classified as non-combustible fuel. Alternatively, it can be decomposed in a catalytic bed reactor and separated into Hydrogen and Nitrogen using PSA (pressure swing adsorption) system. The resulting Hydrogen can be stored to run a Fuel cell car similar to Honda FCX. Ammonia, as a Hydrogen carrier can substitute gasoline as an alternative fuel for transportation and power generation. All necessary technologies and systems are commercially available to make it a commercial reality.

Tuesday, May 8, 2012

Power generation with Ammonia


Majority of current power generation technologies are based on thermodynamic principles of heat and work. Heat is generated by chemical reactions such as combustion of coal, oil or gas with air or pure oxygen. This heat of combustion is then converted into work by a reciprocating engine or steam turbine or gas turbine. The mechanical energy is converted into electrical energy in power generation and as a motive force in transportation. The fundamental principles remain the same irrespective of the efficiencies and sophistications we incorporated as we progressed. The efficiency of these systems hardly exceeds 30-40 of the heat input, while the remaining 60-70 heat is wasted. We were also able to utilize this waste heat and improved the efficiency of the system by way of CHP (combined heat and power) up to 80-85%.But this is possible only in situations where one can utilize both power and heat simultaneously. In a centralized power plant such large heat simply dissipated as a waste heat through cooling towers and in the flue gas. This is a huge loss of heat because a substantial portion of heat of combustion is simply vented into the atmosphere in the form of greenhouse gases. If ‘greenhouse gas’ and ‘Global warming’ were not issues of concern to the world, probably we would have continued our business as usual. Generation of heat by combustion of hydrocarbon is one example of a chemical reaction. In many chemical reactions, heat is either released or absorbed depending upon the type of reaction, whether it is exothermic or endothermic. Sometimes these chemical reactions are reversible. It may release heat while the reaction moves forward and it may absorb heat while it moves backward in the reverse direction. By selecting such reaction one can make use of such energy transformations to our advantages. One need not release the heat and then release the product of reaction into the air like burning fossil fuels. Ammonia is one such reaction. When Hydrogen and Nitrogen is reacted in presence of a catalyst under high temperature and pressure the reaction goes forward releasing a large amount of energy as practiced in industries using Heber’s process. The heat released by this reaction can be converted into steam and we can generate power using steam cycle. The resulting Ammonia can further be heated in presence of a catalyst by external heat due to endothermic nature of the reaction and split into Hydrogen and Nitrogen. However, such heat can be supplied only from external sources. One University in Australia is trying use the above principle by using solar thermal energy as a source of external heat. The advantage of this system is power can be generated without burning any fossil fuel or emitting any greenhouse gas. One can use renewable energy sources such as solar thermal and also use Ammonia as a storage medium. Ammonia is a potential source of energy to substitute fossil fuels. However, such Ammonia is currently synthesized using Hydrocarbon such as oil and gas. The source of Hydrogen is from synthesis gas resulting from steam reformation of a Hydrocarbon. Hydrogen can also be derived from water using electrolysis using renewable energy source. In both the above cases, renewable energy is the key, without which no Hydrogen can be produced without a Hydrocarbon or an external heat is supplied for splitting Ammonia. Ammonia can also be split into Hydrogen and Nitrogen using external heat. The resulting Hydrogen can be used to generate power using a Fuel cell or run a Fuel cell car. Nitrogen also has many industrial applications.Thereoefore Ammonia is a potential chemical that can substitute fossil fuels in the new emerging renewable economy.

Friday, March 30, 2012

Sustainable Hydrogen from bio-waste

Substituting fossil fuels with Hydrogen is not only efficient but also sustainable in the long run. While efforts are on to produce Hydrogen at a cost in par with Gasoline or less using various methods, sustainability is equally important. We have necessary technology to convert piped natural gas to Hydrogen to generate electricity on site to power our homes and fuel our cars using Fuelcell.But this will not be a sustainable solution because we can no longer depend on piped natural gas because its availability is limited; and it is also a potent greenhouse gas. The biogas or land fill gas has the same composition as that of a natural gas except the Methane content is lower than piped natural gas. The natural gas is produced by Nature and comes out along with number of impurities such as Carbon dioxide, moisture and Hydrogen sulfide etc.The impure natural gas is cleaned and purified to increase the Methane content up to 90%, before it is compressed and supplied to the customers. The gas is further purified so that it can be liquefied into LNG (liquefied natural gas) to be transported to long distances or exported to overseas. When the natural gas is liquefied, the volume of gas is reduced about 600 times to its original volume, so that the energy density is increased substantially, in order to reduce the cost of transportation. The LNG can be readily vaporized and used at any remote location, where there is no natural gas pipelines are in existence or in operation. Similarly Hydrogen too can be liquefied into liquid Hydrogen. Our current focus is to reduce the cost of Hydrogen to the level of Gasoline or even less. Biogas and bio-organic materials are potential sources of Hydrogen and also they are sustianable.Our current production of wastes from industries, business and domestic have increased substantially creating sustainability isues.These wastes are also major sources of Greenhouse gases and also sources of many airborne diseses.They also cause depletion of valuable resources without a credible recycling mechanisms. For example, number of valuable materials including Gold, Silver, Platinum, Lead, Cadmium, Mercury and Lithium are thrown into municipal solid waste (MSW) and sewages. Major domestic wastes include food, paper, plastics and wood materials. Industrial wastes include many toxic chemicals including Mercury, Arsenic, tanning chemicals, photographic chemicals, toxic solvents and gases. The domestic and industrial effluents contain valuable materials such as Potassim, Phosphorous and Nitrates. We get these valuable resources from Nature, convert them into useful products and then throw them away as a waste. These valuable materials remain as elements without any change irrespective of the type of usages.Recyling waste materials and treatment of waste water and effluent is a very big business. Waste to wealth is a hot topic. The waste materials both organic and inorganic are too valuable to be wasted for two simple reasons. First, it pollutes our land, water and air; second, we need fresh resources and these resources are limited while our needs are expanding exponentially. It is not an option but an absolute necessity to recycle them to maintain sustainability. For example, most of the countries do not have Phosphorous resources, a vital ingredient for plant growth and food production. Bulk of the Phosphorus and Nitrates are not recovered from municipal waste water and sewage plants. We simply discharge them into sea at far away distance while the public is in dark and EPA shows a blind eye to such activities. Toxic Methane gases are leaking from many land fill sites and some of these sites were even sold to gullible customers as potential housing sites. Many new residents in these locations find later that their houses have been built on abandoned landfill sites. They knew only when the tap water becomes highly inflammable when lighting with a match stick. The levels of Methane were above the threshold limit and these houses were not fit for living. We have to treat wastes because we can recover valuable nutrients and also generate energy without using fresh fossil fuels. It is a win situation for everybody involved in the business of ‘waste to wealth’. These wastes have a potential to guarantee cheap and sustainable Hydrogen for the future. Biogas is a known technology that is generated from various municipal solid wastes and effluents. But current methods of biogas generation are not efficient and further cleaning and purifications are necessary. The low grade methane 40-55% is not suitable for many industrial applications except for domestic heating. The biogas generated by anaerobic digestion has to be scrubbed free of Carbon dioxide and Hydrogen sulfide to get more than 90% Methane gas so that it can be used for power generation and even for steam reforming to Hydrogen generation. Fuel cell used for onsite power generation and Fuel cell cars require high purity Hydrogen. Such Hydrogen is not possible without cleaning and purifying ‘Bio-gas’ significantly. Hydrogen generation from Biogas or from Bioethanol is a potential source of Hydrogen in the future.

Thursday, March 22, 2012

Solar energy storage with Battery or Hydrogen?

Renewable energy industry has slowly but steadily started expanding in many parts of the world in spite of high cost of investment and high cost of energy. Countries like US, Germany and China are now investing on large scale solar and wind technologies, opening new avenues for investments and employment opportunities. Many of these technologies will undergo number of changes over a period of time before it can completely substitute fossil fuels. How long this process will take will depend upon number of factors; but the single biggest driving force will be ‘the issue global warming and its consequences” and also on uncertainties over oil reserves in the world. Nothing dramatic will happen in the near future except the concept of alternative source of energy will expand rapidly. It is also an opportunity to discover new forms of fuels, power generation and distribution methods. The concept of solar energy is now well-recognized as an alternative source of energy because, it is abundantly available, it is clean, generates no pollution and it is silent. The major raw materials such as Silica and Gallium Arsenide are also available but some of the rare earth materials used in PV industries and batteries, are available only in certain parts of the world. China is endowed with many such rare earth resources. For example, Lithium has limited resources and currently bulk of it is produced from natural brines similar to the one at Atacama deserts in South America. It is also available in the form of minerals and ores which many countries are now trying to exploit commercially. The storage of energy from solar and wind is currently done using deep cycle batteries, most of which are Lead-acid batteries. Bulk of the used Lead acid batteries are recycled but the demand for such batteries keeps increasing. The sheer weight of these batteris, space required to install them, capacity utilization, capacity constraints, regular requirement of maintenance and life cycle are some of the issues that are critical for renewable industries. In deep-cycle batteries, discharging stored energy below certain levels dramatically reduces the life span. Hot climate conditions have certain impacts on maintenance of such batteries. Life of a battery is critical because when you calculate the cost of energy over the life cycle of 25 years, the number of replacements of batteries and their cost will have a dramatic effect on the cost of energy. Batteries are indispensable tools in energy industries but, their usage can be minimized to a great extent by using Hydrogen as a storage medium. Let us analyze a simple example of a PV solar system for power generation. We made a computer simulation on three different scenario for a PV solar system for a small residence with power consumption at 15,500kwhrs/day. First simulation was based on PV solar, direct grid connect, without any storage batteries but connected directly to the grid, assuming the grid power tariff is at $0.10/kwhrs and sale to grid tariff at $ 0.30/kwhrs.The second simulation was based on grid independent system using battery storage for 8 hrs autonomy. The third simulation was also grid independent, but solar power was connected to an Electrolyzer to generate Hydrogen and store it in a tank. We used a small capacity battery, less than twenty percent of the capacity used in the previous case and a Hydrogen storage with Fuel cell along with an inverter. The stored Hydrogen was used to generate power to meet the requirement of the residence, instead of supplying power directly from the battery. The cost of energy using direct grid connect was the lowest $$0.33/kwhrs, while Grid independent with battery storage ,the cost of power was $1.20/kwhrs.In third scenario with Hydrogen and Fuel cell, the cost of power was $ 1.90/kwhrs, but there was surplus Hydrogen in the storage tank. With Hydrogen as a storage medium, the cost of power is high due to initial investment but it is maintenance free and ideal for remote locations. The Hydrogen and Fuel cell solution though expensive, has a number of advantages. The power generated by PV solar is stored in the form of Hydrogen instead of storing in batteries. A single battery is used to maintain a steady current to Electrolyzer but bulk of the energy is stored in the form of Hydrogen. Another advantage with this system is that stored Hydrogen can also be used as a fuel for residential heating as well as to fuel your car.

Monday, March 19, 2012

How to power your home and fuel your car with Hydrogen?

There is a general opinion that Hydrogen is dangerous or explosive; people are often reminded of Hindenburg accident or Hydrogen bombs. Hydrogen is as safe as Gasoline or Butane gas. It should be handled with care like any combustible material. We have used Hydrogen in industries for so many decades and transported by pipelines across thousands of kilometers; the methods and procedures of handling Hydrogen is well established. It is a very light, colorless and odorless gas and it can easily escape into the atmosphere. Hydrogenation of vegetable oils for production of certain Margarines is one of the classical industrial examples of Hydrogen usage. When 100m3 Hydrogen is compressed to 10,000psi pressure, it is reduced to just 0.163 m3 by vlume.That is how the Hydrogen storage space is reduced in passenger cars. This volume of gas can give a mileage of 652 miles using Fuel cell power. The only emission is just pure water vapor! No noise, no smoke and it is entirely a new experience driving a Hydrogen Fuel cell car. Powering your home with Hydrogen or fuelling your Fuel cell car is not very difficult. It is expensive compared to grid power for two simple reasons. Grid power is generated by power generation companies somewhere else using coal, oil or gas and transmitted across to millions of people.Therefore investment on power generation is shared by millions of people through their monthly energy bills. When you use the grid power, you do not pay any large sum except, a small deposit of few hundred dollars towards connection fee, and you pay your bills based on your monthly electricity usage. But when you try to generate your own power using a solar panel or Fuel cell then you have to make an investment fully upfront. Of course your bank can help financing the system. However, when you calculate the energy cost over the life period of 25 years, you can clearly see the value of such investment. The grid power cost will only increase and never decrease while your generation cost will decrease as the time passes. The future energy cost is likely to increase substantially due to various factors. You can export surplus power to the grid and your payback time will be reduced as the energy cost increases. The first step in powering your home is to calculate your power requirements accurately in terms of watt.hrs.How many appliances you will be using and how many hours you will using each of these appliances per day. Suppose you estimate 15,000 watt.hrs/day or 15kwhrs/day of power, and then a small Fuel cell consuming 1 Kg/day of Hydrogen or 30 kgs/month of Hydrogen will be sufficient to meet your power demands. Similarly you can calculate the amount of Hydrogen you will be using as a fuel for your Fuel cell car. For example if you will be driving your Fuel cell car for 1000 miles per month, then your Hydrogen requirement will be about 14 kgs/month. Your Hydrogen requirement per month for both power and car together will be 44 kgs only. Your total power requirement to generate the above Hydrogen will be 2464 kwhrs/month costing less than $250 per month for both power and fuel. Of course, you need to calculate other fixed costs on the investment. You can export your solar power at a higher tariff to the Government and import your power requirement from the grid during off-peak season at a lower tariff and generate Hydrogen and store it. You can generate your power as and when you need, and you are in complete control of your situation, even if there is a blackout due to grid failure!

Sunday, March 18, 2012

Tame the Renewable with Hydrogen

The sun is bright and warm and your roof top solar panels and solar heaters are working hard to generate power and hot water. But the rate of power generated is too small to use immediately. The hot water is not hot enough for your shower. Your 200watt rooftop solar panel generates only 0.12 kwhrs after 5 hours of hard work. It does not meet your expectations. You expect 200 watts solar panel to generate about 1000 watt.hrs (1kwhr) in 5 hours. It is not happening. You don’t think renewable energy can meet your electricity demand. There is a strong wind in the island and the wind turbines are rotating faster than usual but there are hardly any people living there. Wind turbine generates good power when the wind velocity is above certain level. But the electricity generated by the wind has no immediate takers. There is a good rain this year and the dams are overflowing and the Hydro is generating surplus power but not many people are living near the catchment area. The power has to be transmitted hundred of kilometers to the nearby town through a sub-station. When the dams are dry there is hardly any power generation and power supply is rationed to the town. When there is a demand for power Mother Nature does not offer the resources for power generation. When Mother Nature offers the resource we do not need power. This anomalous situation is the single largest obstacle that is undermining the potential of renewable energy. Of course, the high initial cost and half-hearted approach by Governments to offer subsidies or grants for renewable energy are other factors that add to the anomaly. The only option to get over this situation is to store the energy 24x7 when it is generated and use them when we need them. It requires good storage technology, automation and information technology that can communicate with Natures energy resources and harness them, store them and deploy them judiciously and intelligently to meet our demands. Current battery technology cannot be a long term sustainable solution; it is expensive, requires constant maintenance and replacement, which adds to the expensive initial investment on renewable systems. The best option is to generate Hydrogen on-site whenever sun shines or wind blows and store them under pressure that can be used as and when we require electricity using Fuel cell. It is easier to handle gas than stored electricity in batteries. Batteries are very heavy, has a limited life cycle and poses health hazard and not suitable for large scale power storage and not sustainable in the long run. An Elecrolyzer can generate Hydrogen from water onsite whenever there is a sun or wind energy available and they can operate from 10% to 100% capacity depending upon the availability of renewable resources. The surplus power from Hydro can be converted into Hydrogen and stored. With so much advancement in information and communication technology, harnessing nature’s energy, storing them and deploying them in a timely manner is not major issue. Hydrogen can bridge the gap between Natural resource availability and human demand. This is what science is all about. We developed science by learning from Nature or duplicating Nature and Renewable energy is nothing different.