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Tag Archives: Fuel cell

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 200 watt 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 24×7 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 when sunshine’s or wind blows and store them under pressure that can be used as and when we need 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 Electrolyzer can generate Hydrogen from water on site when a sun or wind energy available and they can work 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 Nature 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.

We have been using fossil fuels like diesel, petrol and natural gas for power generation and transportation from the time of industrial revolution. The basic fuel and the combustion technology are practically the same with efficiencies less than 40%. In fact we have become very complacent with both the fuel and the combustion technology and there were no major research and development on both the above issues. In fact we became completely dependent on these two issues and there was no real breakthrough either in substituting the fossil fuel or in the combustion technology. The basic reason behind this situation can be attributed to the discovery of electromagnetism, which opened the way for electricity generation as well as transportation. In both these industries, the key part is the motor which provided a rotary motion. This rotary motion generates electricity in turbines and such motion is created by combustion of a fuel, which is invariably a fossil fuel. We have carried on this for few decades before the emission of greenhouse started rising abnormally and became an issue.

We are now at cross roads wondering what the future holds for the world. Is it possible to carry on the business as usual or look for an alternative source of energy? We started looking at various sources of energy as an alternative. Any alternative energy source should meet two critical parameters namely the lower or no carbon emission and sustainability. Low carbon can be achieved by few methods. The immediate option is to maximize the energy efficiency of existing systems so that for the given input of fuel the output is much higher than what we have achieved all these years. But this increase in efficiency should be real to achieve the emission levels of greenhouse suggested by the UN panel on climate change.

The second option will be to switch over to different fuels with less carbon emission e.g., coal-fired power plants switching over to gas-fired power plants using combined cycle. Retrofitting organic Rankin cycle as a bottoming for steam turbines to squeeze out some extra energy. Decentralizing the power plants in a phased manner in favor of distributed energy systems where gas, instead of electricity, can be supplied to each industry, to generate their own power using CHP process. All these measures can help reduce the emission level but our dependency on fossil fuel will still continue.

W can look at a completely different fuel source and new technology for power generation and transportation. If we look at carefully there are not many alternative fuel sources except Hydrogen that could meet these limits. We are also trying to develop bio fuels. But biofuels are also organic chemicals with carbon backbone which will generate greenhouse emission. Moreover bio fuel sources such as palm oil, corn are also food sources. There is an indiscriminate deforestation and plantation of palm trees in tropical countries like Malaysia, Indonesia and PNG. The focus is now shifting to carbon based organic compounds like biofuel and biogas. This will create a situation where food crops will be substituted with energy crops creating food shortage.But the carbon dioxide level in the atmosphere may not be reduced drastically by these methods.

We need to develop an energy source which does not emit any carbon emission and at the same time we should be able to use existing technology to the possible extent. Only Hydrogen can meet these requirements. In the current situation it is impossible to substitute fossil fuels in a short span of time. We can cut fossil fuels by blending with Hydrogen to the most extent possible so that we can meet two goals. We can cut the carbon emission and at the same time we can deploy Hydrogen as a blended fuel with fossil fuel and not, pure Hydrogen. Since Hydrogen is a very light gas and readily forms an explosive mixture with oxygen, this opens up a new opportunity to develop Hydrogen assisted combustion process in power generation as well as in transportation. It will be easier to handle a mixture of natural gas and Hydrogen for combustion in Gas turbine, or spark ignited reciprocating engines, as well as, gasoline combustion engines in cars. This will also gives us an opportunity to develop advanced and competitive systems like Fuel cell as an alternative technology for combustion process in due course of time.

The hydrogen assisted combustion technology is much easier, faster and economical and at the same time cut the greenhouse emission to an accepted level. But the source of such Hydrogen cannot be natural gas but only renewable sources. The renewable technologies such as solar, wind, geothermal, OTEC (ocean thermal energy conversion) should generate renewable Hydrogen. This is the key for sustainability as well as for greenhouse gas mitigation. These two benefits are too attractive to ignore and it is time we move from total fossil fuel to Hydrogen blended fossil fuel. The blended fuel along with the energy efficiency measures suggested above should go hand in hand, so that we may get over this turbulent period of financial crisis and global warming.

It is also possible that Hydrogen assisted combustion be adopted for coal-fired power plants by simply firing coal slurry, finely powdered coal blended with water and conveyed pneumatically for firing boilers and also for gasification process to generate syngas for IGCC (Integrated gasification and combined cycle) applications. Syngas production will be critical in the near future for a smoother transition from fossil economy to Hydrogen economy irrespective of the route we adopt.

In a Regenerative fuel cell the results of redox reaction between Hydrogen and Oxygen, are power and water; the above reaction can be reversed in the same electrochemical process to regenerate hydrogen and oxygen. Such a system is called ‘regenerative fuel cell’. It is a perfect example of a closed circuit system. In ancient Hindu mythology there were citations that claim water came from fire and fire came from water. Two gaseous elements Hydrogen and oxygen reacts violently rather explosively resulting in cool water. Perhaps Hindu mythology terms this reaction as fire which results in water. Similarly by passing a direct current into water, it splits water into oxygen and regenerates Hydrogen, which is a symbolic representation of Fire. Many would have watched a number of ‘you tube videos footings’ on water gas. The water gas or Brown’s gas is a mixture of Hydrogen and oxygen along with un-dissociated water molecules liberated during the process of electrolysis. It can be lit into a flame similar to Oxy-acetylene flame and can be used even to cut metal plates. That is the power of brown’s gas, which I call Oxy-Hydrogen gas. This torch is commercially marketed for metal cuttings applications. But production of pure Hydrogen completely free from Oxygen is a matter of great commercial importance.

Hydrogen is one of the lightest gases and it has a strong bondage with noble metals like Platinum and Palladium. Platinum  catalyst with carbon as a carrier has a wider industrial applications such as hydrogenation in fine chemicals and pharmaceuticals. The author has experience in such applications in bulk drug manufacturing such as Ephedrine and Paracetamol. In a PEM (Proton exchange membrane fuel cell) MEA (membrane electrode assembly) is the heart. The Platinum catalyst coated on the surface of the ‘Nafion’ membrane reacts with gaseous Hydrogen gas. It strips the electron from hydrogen atom while the polymer membrane allows only proton to pass through. The expelled electron flows around the circuit. Flow of electron is nothing but current or electricity. The proton crosses the membrane and reacts with incoming Oxygen through cathode forming water. It is an exothermic reaction and generates heat similar to any combustion reaction, that has to be dissipated.In larger installation we can use this waste heat for a typical CHP (combined heat and power applications) such as power and steam or chilled water or for space cooling. Fuel cell (based on Hydrogen fuel) operates quietly with absolutely no emission except water, and of course, there is no smoke. It is an ideal power source for 24×7 applications such as hospitals, call centers, departmental stores and continues process industries.

In the reverse process of a Fuel cell, the electrochemical device becomes an Electrolyzer splitting water into Hydrogen and oxygen. The electrolyzer works the same way as Fuel cell except in reverse direction; feed is de-ionized water and the products are Hydrogen and Oxygen. In bipolar alkaline electrolyzer, a catalyst such as potash lye is added where in solid polymer electrolyzers platinum acts as a catalyst like a Fuelcell. The generated Hydrogen comes under pressure obviating the use of an extra compressor. The Hydrogen is stored in cylinders for further usage.

As I mentioned in my previous articles the power required to split water into Hydrogen and Oxygen is more than the power generated from the resulting Hydrogen by a Fuelcell.That means an input of excess energy is necessary for a regenerative fuel cell to run successfully .Where this energy will come from depends on the cost benefit analysis to be made. Surplus Hydro power is ideal for such regenerative fuel cell applications. But we can also use various other renewable energy sources such as wind, solar, geothermal, OTEC depending upon the site and applications. The biggest advantage with regenerative fuel cell is there is no other input except the excess power to be supplied. When renewable energy is deployed on large commercial scales then regenerative fuel cell will become a clean solution of the future. I have no doubt in my mind that this will become a commercial reality. Of course the top policy makers should understand the potential and make a right decision and encourage more business and industries to deploy such systems. The energy costing model cannot be based on fossil fuel model because fossil fuel is not renewable. This is the crux of the problem.

In our future articles we will present case studies of various clean energy systems that are already in commercial operation. I also welcome articles from clean energy professionals with life project experience and problems they face. I welcome comments and feedback from business, industries and people.

Seawater is an inexhaustible source of Hydrogen but the cost of generating Hydrogen from seawater is much higher compared to normal tap water. The quality of water should have a minimum electric conductivity at 0.1 micro Siemens/cm for electrolysis. Even our tap water is not up to this purity and it requires further purification. The electric conductivity of seawater is about 54,000 micro Siemens/cm.The conductivity increases due to the presence of dissolved salts. But seawater can be desalinated using the process of distillation or by the process called ‘reverse osmosis’. In both the above processes, desalination requires a large input of energy in the form of thermal or electrical. Currently the source of such energy comes from fossil fuels, which is one the biggest emitters of greenhouse gas emission. Many countries in the Middle East have shortage of fresh water and most of these countries depend on desalination of seawater for their fresh water requirements. The cost of desalinated water varies from $ 1.00 to $ 1.75/m3 depending upon the capacity, site and the cost of energy. The fresh water for potable purpose normally has a TDS (Total dissolved solids) of 500ppm (parts per million) or less and this can further be lowered to a required level using reverse osmosis.

Currently Hydrogen is generated as a by-product on an industrial scale by electrolysis of saturated sodium chloride brine during the production of Caustic soda. Chlorine is another by-product in the above process. Most of Caustic soda manufacturers use Hydrogen as a fuel or for the production of Hydrochloric acid. But there is an opportunity in caustic soda plants to use Hydrogen to generate more electricity using PEM (Proto exchange membrane) Fuel cell suitable for their electrolysis. This will aid these industries to cut their energy consumption, which is one of the highest in Chemical industries.

Alternatively, offshore wind turbines can be installed to generate power for seawater desalination and Hydrogen production. Offshore wind turbines generate 50% more energy than onshore wind turbines. An integrated process to generate fresh water, Hydrogen using wind turbine is an interesting renewable energy application. The stored Hydrogen can used to generate electricity in remote islands where diesel is used as a fuel. Most of the island in Pacific use diesel predominantly for boat as well as for power generators at exorbitant costs. The wind velocity in such islands is good to generate cheap and clean electricity. For example, the island of PNG has a severe power shortage and it is well located near Coral Sea, which has one of the highest wind velocities in Pacific Ocean. An average wind velocity of 7mts/sec and above is an ideal place for wind turbines. Since these islands are small with less population, wind generated Hydrogen is an ideal solution for their power problems. They can also desalinate seawater to supply drinking water using wind generated power. In fact they can also use Hydrogen as a fuel for their boats and generate power for their cold storage for fisheries. International financial institutions and local banks should come forward to fund such projects instead of funding diesel boats and generators. These islands have pristine water and abundant fish and their main income is only tourism.

Sun, Sand and wind is an ideal combination to generate renewable power all round the year and for tourism industry. It is an opportunity these islands cannot afford to miss. The author is personally involved in a wind based Hydrogen solution for a small island in pacific. The people of this island welcome such projects because it guarantees them an uninterrupted supply of clean power and drinking water. Otherwise they have to sell most of fish catches in a nearby city to buy diesel and drinking water just to survive!

 

 

Hydrogen is the cleanest source of energy that can power your homes and fuel your cars. It can potentially substitute diesel and petrol or coal and clean up our environment. Hydrogen has been manufactured industrially for the past several decades and transported across thousand of kilometers by pipelines in Europe. The science and technology of Hydrogen is well known but its application to generate power and fuel a car is relatively new. The gasoline internal combustion engines that drive our gasoline cars can be modified to suit Hydrogen fuel. But the physical and chemical properties of Hydrogen gas created a necessity to alter existing gasoline engines for commercialization. But such conversion has been painfully slow for couple of reasons. There is a stiff resistance from gasoline cars to switch over to Hydrogen because they have a well established infrastructure to manufacture gasoline cars and to supply gasoline through well established distribution network. But Hydrogen cars lack both of them. Even if the cars can be modified for Hydrogen, there are no sales or distribution network for the fuel Hydrogen, similar to Gasoline. Even consumers need to be educated that Hydrogen is safe, environmentally friendly and we need not depend on import of oil and so on. It is a blessing in disguise that Hydrogen can be generated by each home, business and industries for their captive use from their tap water. Recently Hydrogen fuelled scooters have been introduced in the market. There are number of advertisements in the media too; that you can fit a Hydrogen generator at your car that will reduce your gasoline bills substantially and also cut your emissions.But these Electrolyzers can generate only water gas and not a pure Hydrogen. Yet such simple devices can help reduce your petrol bills to an extend .If things are so simple why are we still struggling with high crude oil prices and increasing electricity bills? Let us examine this in detail. Water (H2O) can be split into Hydrogen (H2) and Oxygen (O2) by simply passing an electric current through water using a battery. The water disassociate as follows: 2    H2o———   2 H2+ )2 Stochiometrically, it means 36 lits of water will generate 4 Kgs of Hydrogen and 32 kgs of Oygygen.The current PEM (Proton exchange membrane) Fuel cell car (Honda FCX clarity) can drive 100 miles with just 0.105 kgs of Hydrogen from 5000 psi Hydrogen tank. Similarly 4kgs of hydrogen can generate about 100 kws of electricity using PEM Fuel cell, based on a conservative estimate; but 4Kgs of gasoline can generate only 15 kW electricity. The gasoline engine offers only 100km mileage from 13 kgs (16lits) of gasoline. In other words, 0.105 kgs of Hydrogen at 5000 psi gives the same mileage as 16 lits of Gasoline.  This is the amazing power of water, yet to be unleashed! The tap water is suitable to generate Hydrogen by adding a little amount of potash lye to improve the electrical conductivity. An Alkaline water electrolyzer can be attached to the water tank to generate required amount of Hydrogen based on the above calculation. The resulting Hydrogen has to be compressed to a required level. The power consumption to electrolyze water will be about 75-80 kwhrs per Kg of Hydrogen generated at 5000 psi.Therefore 4Kgs of Hydrogen will need a power of 300kwhrs costing about $30 for a total mileage of 3800 miles. You will need a small reverse osmosis unit to be attached to your water tap so that the water is de-ionized so that there is no precipitation in the Electrolyzer or reduction in the efficiency of electrolysis. Recently, Suzuki Bargeman introduced Hydrogen Fuel cell scooter which claims to offer a mileage of 200km from 12 lits Hydrogen (carbon composite material) tank at an higher pressure of 10,000psi.The future of Hydrogen car is very promising and finally the world can hope to get rid of smoke and noise from our roads and cities.

This article provides an overview on Hydrogen cars and how we can generate renewable hydrogen to fuel these cars. There are two well-known brands of Hydrogen based cars already in the market, BMW7 and Honda FCX Clarity models.

BMW7 works on Hydrogen Internal Combustion engine fuelled by Liquid Hydrogen. It is a 6 Liters V12 engine with 191Kw capacity and 390 N of torque. It offers 100km from 50 Liters of Liquid Hydrogen with a density of about 70-80gms/lit and offers 100kms from Gasoline of 16.7 liters. It has a capacity of 170 liters for liquid Hydrogen storage at the rear end of the car. It can run both on Hydrogen as well as on Gasoline. Liquid hydrogen has a better power density but liquefaction is a cryogenic technology and consumes power for liquefaction. The storage tank also is of special construction because Liquid Hydrogen is stored at -253C.

Honda FCX Clarity car is fuel cell car fuelled by compressed Hydrogen gas. It offers 100kms for 3.5 lits of Hydrogen (at 5000 psi pressure with density at 30gms/lit.). It has Hydrogen storage of 3.92kgs kgs with a total mileage of 240miles. Increasing Hydrogen storage gas pressure up to 10000psi, the Hydrogen power density is considerably increased making it comparable with liquid Hydrogen. Moreover fuel cell car is silent while driving because there is no combustion engine.
BMW is able to use their existing conventional internal combustion engine with slight changes suitable for Hydrogen so that they can use their existing infrastructure. But Honda FCX uses proton exchange membrane Fuel cell. It is an electrochemical device that converts Hydrogen into electricity which runs the motor for transmission of power. It is similar to an electric car in which power is stored in batteries and used to drive the motor for transmission. The only difference is the power is generated in Fuel cell car as and when hydrogen is supplied whereas in Electric cars, power is drawn from stored energy from the battery.

We can inject pure Hydrogen along with Gasoline, CNG or LPG to assist the combustion to save fuel consumption up to 30% and to reduce harmful emissions. The conventional gasoline cars can be fitted with water electrolyzer to generate Hydrogen using the car battery. The electrolyzer currently sold in the market is quite different. They generate ‘water gases’ and not pure Hydrogen. They electrolyze water using pulsating DC current which essentially breaks down water into Hydrogen and oxygen molecules. The complete mixture of Hydrogen, Oxygen and undissociated water molecules are injected into fuel manifold of the car. The hydrogen will assist in the process of combustion to certain extend and help save the fuel consumption of gasoline.

Renewable Hydrogen is a potential source for fuelling automobiles. One can use solar panels and simple tap water to generate hydrogen gas and store them under high pressure in cylinders. We will be releasing an eBook in the near future to design a suitable Renewable Hydrogen system and install them at homes and businesses for power generation as well as to fuel two-stroke engines such as scooters and bikes. Initially the book will offer DIY kits to design and install power generation for homes and businesses up to 10Kw capacity electricity generation. We will be conducting trials on two-stroke engines using renewable Hydrogen to get approvals from proper transport authorities for safety and usage on Indian roads.

Hydrogen can be safely handled as long as we take appropriate safety measures as we normally do while handling petroleum products like gasoline or butane gas. It may look like a daunting task to fuel a car with Hydrogen gas but in reality, all necessary equipment and systems are commercially available including High pressure Carbon fiber tanks fully tested and approved.

Water makes up 71% of the planet earth and it is the most potential energy source of the future. Water is a product of combustion between Hydrogen and Oxygen, two most abundantly available elements and   vital for life on earth. The bondage between Hydrogen and Oxygen is so strong that it requires a certain amount of energy to separate them. Separation of Hydrogen and Oxygen using the process of Electrolysis is a well-known technology. Separation of water by high temperature using Thermolysis has also been studied.  In both the processes the separation of Hydrogen and Oxygen after decomposition is a key step because of the strong affinity between the two elements. Hydrogen has to be separated in a pure form without any trace of Oxygen. Currently most of Hydrogen is generated commercially by steam reforming natural gas because of its easy availability as piped gas in many developed countries. Moreover steam reforming is a well established commercial technology that has been used for decades in chemical process industries. The hydrogen resulting from steam reforming is acceptable for combusting in Hydrogen internal combustion engines but not pure enough for a Fuel cell car. Any trace of impurity from natural gas such as Sulfur or Mercaptans can potentially poison the catalyst used in fuel cell which is very expensive. Hydrogen with purity less than 99.99% is not recommended for Fuel cell applications.

Currently there are few issues to be addressed before Hydrogen becoming a commercial fuel. The energy required to separate Hydrogen from water by commercial electrolysis is about 6Kws (kilowatts) to generate 1 m3 (cubic meter) of Hydrogen. Two key factors for electrolysis are purity of water and  direct current source. Water of certain purity is a critical part for Hydrogen generation. Deionized water with electrical conductivity less than 0.10 micro Siemens/cm is required. Normal drinking water conductivity is less than 100micro Siemens/cm. The potable water can be deionized with reverse osmosis system to get necessary quality. In fact both high purity water and direct current are not commercially available. A renewable energy sources such as solar or wind that generates direct current can be used for electrolysis. This will drop batteries and rectifier that we normally use in renewable energy systems. The generated Hydrogen can be stored in cylinders under high pressure. The stored hydrogen is the stored energy that can be used as and when required.  We can use the stored Hydrogen to generate electricity to meet our power requirement whether it is a home or business or industry. The major advantage with this system is that we can generate power when we need and we don’t have to depend on the grid power. We can also export surplus power to the grid. In fact all DC appliances can be connected with DC power from Fuel cell and operated to improve the efficiency. Such a system is ideal for remote locations without any grid supply such as remote villages or islands.

The same stored Hydrogen can also be used as fuel for a car whether it is a combustion engine or a Fuel cell car. Hydrogen can be compressed and stored under high pressure. Alternatively, Hydrogen can be stored using metal hydrides in smaller volumes. Honda introduced the first fuel cell car in the market in 1999. Since then they have made considerable improvements. Honda FCX Clarity, sedan offers a mileage of 270 miles for a single cylinder of Hydrogen at 5000 psi pressure. They are introducing a latest model with Hydrogen pressure at 10,000 psi which will considerably improve the mileage further. Unlike Hybrid cars, Fuel cell cars run silently and experts who have test-driven the car are very much impressed with the performance. Similarly Ford introduced Hydrogen combustion engine 6.8 liters V-10 engine to power E-450 Hydrogen shuttle bus. Ford modified their Gasoline engine to suit Hydrogen fuel.

Substituting Gasoline with Hydrogen is no longer a theory but a commercial reality. More and more research is being undertaken to improve the performance. Currently the cost of Hydrogen cars and Hydrogen fuel is expensive, due to lack of infrastructures to manufacture such cars or to distribute Hydrogen. However these cars will soon replace gasoline cars. Similarly homes and business can generate their own electricity for their daily use using stored Hydrogen. Water will become the fuel of the future and Hydrogen will clean up the air that has been heavily polluted by fossil fuels for decades.

Our modern civilization has been shaped by oil or Hydrocarbons for several decades to such an extent that there is no immediate substitute for petrol, the world can count on. In fact the world has been complacent about the availability of Hydrocarbon, its applications and its future. Political leaders have competed with each other to make sure that their supply of oil and gas is guaranteed as a  matter of national security. Some countries even waged wars to secure oil fields. This situation is getting worse, as the supply of oil and gas are becoming uncertain and supplies dwindling. Each and every human being in the world is affected by oil and gas in one way or other, irrespective of the size, geography and rate of industrialization. The main reason for this situation is, the contribution of hydrocarbons made in the field of power generation and transportation.

Currently more than 80% of power generation comes from fossil fuels such as oil, gas and coal. The entire transportation industry all over the world depends on oil and gas. The petrochemical industry’s contribution to our modern civilization is tremendous. It encompasses a whole range of industries whether it is fertilizers or plastics and resins or chemical industries or drugs and pharmaceuticals or cosmetic and toiletries and so on. These major industries determine the progress, civilization and industrialization of a nation. Countries who have vast resources of oil and gas are one of the richest countries in the world, even though these countries have no other resources. Countries with vast population and resources have to depend on oil and gas imports for their industries and transports. Countries with vast mineral resources cannot run their mines without power or transportation.

It is time we look at why oil and gas has become such a critical components in the progress of a nation and how this situation can be overcome. The two major technologies, which depend upon hydrocarbons, are power generation and transportation. Both these technologies use heat as a primary energy. In power generation, heat energy is converted into mechanical energy and then to electrical energy. In transport industry, the heat energy of the fuel is converted into mechanical energy. In petrochemical industry; oil and gas are converted into various chemical products by various chemical reactions and processes.

If we closely look at the Hydrocarbon molecule, one thing is obvious. In a Hydrocarbon molecule, Hydrogen atoms are attached to carbon atoms. A simple example is, Natural gas or Methane gas, represented by chemical formula CH4. Four Hydrogen atoms are attached to a carbon atom, which actually imparts the heat energy (heat content) to the molecule. Without Hydrogen atoms, it is nothing but carbon. If we look at the heat value of Natural gas and Hydrogen, one will understand that Hydrogen has got a higher heating value. What is more interesting is there will be no greenhouse emission (carbon dioxide or carbon monoxide) by combusting Hydrogen. It is only water that is the byproduct of combustion of Hydrogen. If we can generate power or drive a car by combusting a Hydrocarbon, then why not combust Hydrogen to generate power or drive a car using the same combustion process? Even if one considers Hydrogen as too dangerous to handle, a mixture of a minor part of biogas or natural with Hydrogen should solve the issue. It is certainly possible and only Hydrogen can replace oil and gas. We can use a combustion technology we knew for decades or use Fuel cell technology that we start using recently with Hydrogen. It is a clean technology and it does not emit smoke or make noise. Whichever way we looks at it, only hydrogen can replace Petrol. Sooner it does, better for the world.

 

Power generation using fossil fuels is a well established technology dating back to 1839, when Michael Faraday invented the principle of Electro-magnetism. There was not much of a change in this technology all these years. But recently greenhouse emission and global warming has become an issue; and the world started looking for an alternative source of energy and method of power generation. However it is not an easy task to develop completely a different technology as well as a fuel in a short span of time, while an unabated man-made greenhouse gas emission continues. Scientists  are now warning  catastrophic consequences if we do not curtail greenhouse gas emissions with great urgency.Untill now the world was able to avert some of the potentially  catastrophic events happening, like ozone layer depletion, pandemic bird flu etc.But global warming is a new thereat  that demands an entirely a new solution and a swift action. But most countries in the world are not is a place to curtain greenhouse emission gas, simply because there is no alternative fuel known, except fossil fuels. Renewable energy is relatively a new concept. Though we knew about solar and wind energy sources, we did not persuade  them seriously because they could not compete with conventional fossil fuels. But the time has come for new emerging technologies that can not only compete with fossil fuels but also eliminate greenhouse emissions. The world has invested massively on fossil fuel infrastructures and still investing heavily on oil and gas explorations. Obviously there is no end in sight as far as fossil fuels are concerned and the world is carrying on business as usual.

Meanwhile a new technology based on fuel cell is emerging as an alternative for power generation. Fuel cell is a known concept and it has been successfully deployed in ‘Apollo space programme in space shuttle. This old version of alkaline fuel cells was replaced with PEM (proton exchange membrane) fuel cell or (PEMF) Polymer electrode membrane fuel cell. This new version was used in Gemini’s space programme in sixties. Fuel cell is an electro chemical device that uses Hydrogen gas as a fuel and it operates at ambient temperature. It is like a battery cell. The difference between fuel cell and batteries is the Fuel cell will keep generating power as long as fuel is supplied unlike a battery, where energy is stored in the form of chemical energy and converted into electrical energy when used by connecting through a conductor. Battery needs recharging but Fuel cell requires refueling. The fuel used in Fuel cell is invariably Hydrogen. Conventional power generation involves combustion of fossil fuel (heat energy) which drives a turbine (mechanical energy) to run an alternator to generate power (electrical energy).In fuel cell; Hydrogen gas reacts with oxygen from the atmosphere (electrochemically) to generate power. It produces water as by-product. The efficiency of Fuel cell is about 50-60% compared to 35-40% by steam or gas turbine. In regenerative fuel cell, we can split water into Hydrogen and oxygen using same proton exchange membrane elecrolyzer.We can use the resulting Hydrogen as a Fuel to the PEM Fuel cell to generate power, thus recovering  water. It is a closed circuit system. There are no mechanical moving parts, no combustion, no smoke or no noise. It is a quiet and clean operation. It is a very promising technology that can revolutionize the way we produce fuel and generate power. The Hydrogen and fuel cell combination is used in cars. Honda FCX (fuel cell model) cars work on the same principle and they are already on roads!

One problem with Hydrogen generation is it requires more power to split water, into Hydrogen and oxygen, than the power generated by resulting hydrogen, using Fuel cell. However, this technology will change the future of power generation by eliminating greenhouse emission completely. But how long it will take to become a commercial reality is something we have to wait and see! If political leaders and Governments around the world recognize the potential of this technology and take bold decisions together with swift actions, probably our future generation can breathe a clean air.

Renewable energy is one of the fastest growing energy sources of our times. But still there are many obstacles to overcome, before it can substitute current methods of electricity generation using fossil fuels, or substitute petrol in cars. The main obstacle is, the intermittent and unpredictable nature of renewable energy sources, such as wind and solar. Wind blows only certain seasons of the year and then wind velocity fluctuates widely in a day. Similarly sun shines only certain hours in a day and the intensity of radiation varies widely in a day. The wind velocity and sun’s radiation intensity are critical components in designing a reliable energy system. It is an anomalous situation, when we need power, there is no sun or wind; when sun shines or wind blows, we may not need any power. How to overcome this anomaly? That is the key, in successfully deploying renewable energy technologies.

Currently we are using batteries to store the energy. When there is a wind with reasonable velocity or sunshine with reasonable radiation intensity, we can generate power and store them in batteries. The wind velocity should be above certain threshold limit, say such as, a least wind velocity of 3mts/sec for amount of hours, while designing a wind based energy system. The same principle applies to solar energy and we need certain minimum solar   intensity and several hours. But in reality, we don’t get these minimum operating parameters, which make the design of a renewable system more complicated.

Batteries can accumulate these small energy generations by intermittent sources of wind and sun, and store them. But these batteries have certain life between 3-5 years and requires regular maintenance, replacements.They also have certain charging and discharging cycles and limitations. At the end of its life, it has to be disposed carefully because these batteries are made of lead and acid, which are toxic materials. Many companies are trying to introduce better technologies such as ‘flow batteries’. But experience shows that such batteries are confined to only smaller capacities. Large scale storage is expensive and sometimes it is not economically feasible. Lithium-ion batteries are more efficient than Lead-acid batteries, but they are more expensive so the renewable energy projects become expensive and cannot compete with conventional fossil fuels, in spite of higher tariffs offered by Government as incentives. Moreover the demand for Lithium-ion batteries will increase substantially in the future, as more and more Electric cars are produced. But lithium sources are limited and it is not sustainable.

The best option to develop renewable energy systems is to generate Hydrogen using renewable energy and store them, instead of storing them in batteries. We can use stored Hydrogen to generate power, or use as fuel for the car, as and when we need. There are no maintenance or disposal problems with Hydrogen storage, when comparing with batteries. Hydrogen generators (electrolyzers) can generate Hydrogen when the intermittent power flows from wind or sun. They can run from a range of capacities from 5 to 100% of rated capacity and they are more suitable for renewable energy sources. But there will be a loss of energy, because the amount of power required to generate Hydrogen, is more than the power generated from the resulting Hydrogen by a Fuelcell.The initial cost will be higher, but it will give operational flexibility with least maintenance, and even adoptable to remote sites. Technology is improving to cut the cost of fuel cells and electrolyzers so that Hydrogen based renewable energy will become a sustainable source of energy in the future. Hydrogen is the only solution that can solve both power generation and transportation problems the world is currently facing.

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