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The first few hydrogen atom electron orbitals ...

The first few hydrogen atom electron orbitals shown as cross-sections with color-coded probability density (Photo credit: Wikipedia)

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 clean power generation. That is why most of the Hydrogen is now generated by steam reforming natural gas. Another reason for using natural gas is, to cut the cost of Hydrogen and also, to make 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 prove 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 prove 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.

 

We now 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 has 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. On-site Hydrogen generation using solar thermal using either electricity or heat can 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 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 cut 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.

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.

There is a myth that electric cars will eliminate Greenhouse gas emission and reduce the global warming. Electric car will not reduce the greenhouse emission because; you still need electricity to charge your batteries. Companies promoting electric cars are now planning to set up their own battery charging stations because, customers have to charge batteries of these electric cars every now and then. Otherwise, they will not be able to drive their electric cars continuously.  There is no battery currently in the market that can last more than 28 hours between the charges, though many companies are trying to develop superior batteries. One company claims a Battery(electricity) of 300whr/kg, for their LLithium-ion polymer battery, much superior than other batteries, which can run 600kms, with 6 minutes charging. Though, new batteries such as semi solid Lithium-ion battery, based on the principle of ‘flow batteries’, are promising, it is still, a long way to commercialization. President Obama  has set a set a target of 1 million electric cars in US roads, by 2012.It is estimated that US has to produce about 40 billion dollars worth of domestically produced batteries. A lithium-ion battery which weighs less and stores more energy is the promising technology. But Lithium resources are limited. Battery is the heart of an electric car. These electric cars do not emit smoke, or make noise like petrol cars. But, these two factors alone are not sufficient to substitute traditional fossil fuel powered international combustion engines.

It is also true, that electric cars can cut green house emission to an extent, where fossil fuel consumed cars are replaced with electric cars. To that extend, the fossil fuel consumption by these cars are reduced. But the power to charge the batteries will still have to come from the common grid. Unless the power generation technology using fossil fuels is changed, there will be no dramatic greenhouse gas emission reduction by introducing electric cars. Alternatively, if cars are built on Hydrogen based fuel either using a conventional Internal combustion engine, or by using Fuel cell, then a substantial amount of greenhouse emission can be eliminated. However Hydrogen generation should be based on Renewable energy source only. Whichever way one looks at it, renewable energy is the key. Those Governments and companies who do not invest in renewable energy technologies and systems, now, will have to pay a heavy price, in the future. But even those companies investing on renewable energy technologies, should look beyond current technologies and systems. The best starting point for these industries will be to substitute ‘storage batteries’ with ‘stored Hydrogen’.

It is much simpler to install PV solar panels or wind turbines, and to generate Hydrogen on site, from water. One can store Hydrogen in fuelling stations, and fuel the cars. Honda was the first entrant into this market, who was focusing on fuel cell technology, using compressed hydrogen gas. Alternatively such Hydrogen can be generated from ‘Biogas’ generated from biological wastes and waste treatment plants. All necessary technologies are currently available to make it happen. Governments can try to promote small townships with Hydrogen fuel stations, and show case such models to the rest of the country or other nations to follow. This will help nations to reduce their greenhouse emission and at the same time, they can become self-sufficient in their energy requirements. They no longer have to depend on polluting oil and gas, from few Middle East countries. Countries like India with impressive economic growth heavily depend on oil imports and any slight fluctuation in oil prices can easily upset such growth. It is time Governments around the world take a serious look at Hydrogen, as their alternative energy source. It is just not good enough to promote renewable energy technologies, but they have to develop generation, storage and distribution technologies for Hydrogen. What is needed at this hour is, ‘will, determination and leadership’ on the part of the Governments, like US, China and India, that can set an example for the rest of the world by investing in Hydrogen economy.

We know from the famous equation  of Albert Einstein , that a tiny amount of mass is a vast storehouse of energy. But even the molecular Hydrogen as a result of water decomposition, is a promising energy source of the future. However, the amount of energy we use to split water into Hydrogen and Oxygen is higher compared to the amount of energy that Hydrogen can generate using Fuel celll. But we can mitigate this problem by using Renewable   energy such as PV solar, Solar (thermal), wind energy, geothermal energy, and Ocean thermal energy conversion. The cost of renewable energy is still expensive for two reasons;

  1. We are used to cheap energy from fossil fuels for decades, and we have already recovered most of these investments.

2. A complete switch over to renewable energy technologies will require massive new investment. Unlike the investments we made on fossil fuel infrastructures over several decades, we have to invest on renewable Energy development on a massive scale, and we have to deploy them in a shorter span of time, simultaneously all over the world. Currently there is no such infrastructure in renewable energy industry in existence.

Meanwhile the unabated emission of carbon dioxide by fossil fuels is causing global warming. There are many skeptics on the science on global warming. Such skepticism does not stem from the fact that they have a concrete proof but, ‘such skepticism’ serves their vested interest. Politicians who are in power do not want any increase in the cost of energy, which becomes unpopular among people may eventually, throw them out of power. They say they want to serve people with low cost energy but, neither politicians nor the common man understands the consequences of such measures.

It will be our future generations who will face the brunt of this skepticism, by facing fuel shortage or unaffordable cost of fuel, erratic climate change, and frequent natural catastrophies.It is time for the world to act decisively and swiftly and move towards renewable energy, by massive investment and creation of new skills and jobs on a very large scale.

The companies who have massively invested in fossil power plants, and the governments who depend on the support of such companies and who want to keep the energy cost low, because of its popularity, are the major list of scientists opposing main stream scientific assessment of global warming. The hidden cost of environmental challenges and its consequences is much higher than the savings, due to cheap fossil fuels. It requires a paradigm shift and a sense of social justice, in the minds of Governments and companies. It is not all that difficult to switch over to cleaner technologies. In fact most of the technologies are already available and it requires only a ‘will, bold decision and leadership’ by Governments.

Any clean energy solution should be sustainable in the long run. Hydrogen can meet not only the sustainability but even the transition from fossil fuel to Hydrogen will be smooth. To start with all existing fossil fuel infrastructures can be modified towards Hydrogen generation, and fuel cell based Electricity generation  infrastructures. Of course this will require large investment but compared to a complete shift to renewable energy, it will require only a relatively smaller investment. For example, all fuel stations can be converted into Hydrogen stations by simply installing steam reformers, including LNG based fuel stations. All gasoline based automobiles can be either fitted with Hydrogen IC engines, or converted to fuel cells cars similar to Honda FXL models. If the Governments all over the world can agree for such conversion and a complete shift to Hydrogen economy then, it can become a reality in the next decade. We have to focus on ‘Renewable Hydrogen’, which can come from seawater, a waste source of Hydrogen using renewable energy sources, and Biohydrogen  using from waste organic matters. The future generation will not only have a cleaner and affordable fuel but, a more sustainable future!

Distributed  generation system, is a system that generates power at the point of usage; unlike the centralized electricity generation, where power is generated at a remote place and then distributed to various locations using Power transmission  grids. The centralized systems became popular, due to its convenience, to transmit large power over long distances, under high voltage. However, there are several disadvantages, in centralized power generation and distribution. Most of these power generation plants are using fossil fuels, like coal, oil and gas, whose efficiency is only about 40%; which means, only about 40% of the heat value of the fuel used is converted into electricity, and the balance is a waste heat, discharged in the form of greenhouse gases, into the atmosphere. That is why; power station are the largest emitters of greenhouse gases, in the world. These plants are  not only the biggest emitters of greenhouse gases, but also a very inefficient, because bulk of the fuel is simply combusted and discharged into the atmosphere. With ever-increasing cost of oil and gas, these power plants are ‘white elephants’ that drain the oil and gas resources in the world and turn them into greenhouse gases. Such inefficiencies drive the cost of power high, and also increase the pollution levels. This unabated emission of greenhouse gas has to be curtailed.

At this juncture of global warming, and increasing energy cost, Governments and companies, should encourage distributed energy systems. The advantage with distributed energy systems is, when we generate energy  on site using a fuel, we can use the waste heat  in a productive way, thus increasing the power efficiencies from 40% up to 80-85%.This increase in efficiency, will result, is the reduction in the cost of energy. The power savings from distributed energy system varies  from 10% up to 80%. Industries and business who use continuous processes (24×7) and whose energy bill is substantial, are the ideal candidates for distributed energy systems. It is easier to adapt distributed energy system, with gaseous fuels, like natural gas and Hydrogen, than with liquid fuels such as diesel or solid fuel such as coal.

Distributed energy system can even be installed, using ‘Biogas’, where large quantity of  organic waste or waste water is available throughout the year, like dairy plants, breweries, municipal sewage systems etc.The power generated in DES system, is invariably a direct current (DC), which is usually converted into alternating  using rectifier,   before usage. But, part of this DC load, can be used directly in the form of Dc current, wherever necessary. For example, many consumers are using Light-emitting diode bulbs for lighting, to save energy. In distributed energy system, it is possible to use direct current for these applications because you can save a certain amount of energy in the process of converting DC to AC, and then again AC to DC.In fact, we can connect number of appliances directly  to  direct current.

In addition to the above advantages, we can utilize the waste heat  to generate steam, hot water, chilled water or space airconditioning.For example, if a distributed energy system generates  500 kw Electric power using natural gas, with an efficiency of 30%, the gas consumption will be about 1666 Kws.The remaining waste heat available is about 1166 Kws, which is equal to about 300 TR chilling capacity. This chiller can be used to air-condition an office space. The total efficiency of such system can be as much as 80%.We can reduce the cost of energy as much as 60% or more, in some cases.

Distributed energy system, is the best and cost-effective system to cut energy bills as well as to reduce Greenhouse gas Otherwise the power for air-conditioning has to come from the grid. It is a win situation, for everybody involved. Such system can also be used, with Hydrogen. In fact, the heat value of Hydrogen is much higher than any other fuel, such as coal, oil or gas. Hydrogen is the energy of the future that is not only clean but also sustainable.

Why I say “water and clean energy, are two sides of the same coin?” At the outset, it may sound odd, but in reality, these two are closely interconnected. Let us examine, step by step, how they are connected, to each other, and what are the implications, in terms of cost, and environmental issues.

Take for example, power generation industries. The two basic materials, any power plant require, are, fuel and water. It does not matter, what kind of fuel is used, whether it is a coal based power plant or liquid fuel based plant like Naphtha, or gas based plants, like piped natural gas or LNG Of course, this statement is applicable only, for existing, conventional power generation technologies, and not for PV solar or wind energy, technologies. Let us consider, only power generation, involving conversion of thermal energy, into electrical energy. Today, more than 80% of power generation in the world, is based on thermal power, including nuclear plants. What is the usage of water in power plants? All thermal power plants use steam, as the prime motive force, to drive the turbines, (gas turbine is an exception, but, even in gas based plants, the secondary motive force,  is steam, using waste heat recovery boilers, in combined cycle operations). The quality of water for conversion into steam is of high quality, purer, than our drinking water. The second usage of water is for cooling purpose. The water consumption by power plants, using once through cooling system is 1 lit/kwhr, and by closed circuit cooling tower, it is 1.7lit/kwhr .Only about 40% power plants in Europe, for example, use closed circuit cooling towers, and the rest use only ‘once through’ cooling systems. The total power generated in 2010, by two largest users, namely US and China, were 3792Twhrs and 3715 Twhrs  respectively. The total world power production, in 2008 was 20,262 Twhrs, using following methods.

Fossil fuel: Coal 41 %, Oil 5.50%, Gas 21%, Nuclear 13% and Hydro 16%.

Renewable: PV solar 0.06%, PV thermal 0.004%, Wind 1.1%, Tide  0.003 %, Geothermal 0.3%, Biomass &others 1.30%.

(1Twhrs is = 1,000,000,000 kwhrs)

The above statistics, gives us an idea, on how much water, is being used, by power generating plants, in the world. Availability of fresh water, on planet earth, is only 2.5% (96. 5% oceans, 1.70% ground water, 1.7% glaciers and ice caps, and 0.001% in the air, as vapor and clouds).The world’s precious water source, is used for power generation, while millions of people, do have water, to drink. The cost of bottled drinking water is US$ 0.20 /lit, in countries like, India. This situation is simply unsustainable.

The prime cause, for this situation, is lack of technology, to produce clean power, without using water. The power technology, we use today, is based on the principle of electromagnetism, invented, by Michael Faraday, in the year 1839. That is why, renewable energy, is becoming critically important, at this juncture, when the world is, at the cross road.

In order to overcome, the shortage of fresh water, many countries are now opting, for seawater desalination. Desalination, again, is an energy intensive process. For example 3-4 kwhrs of power is used, to desalinate 1 m3 of water. This  power has to come, from fossil fuel fired, thermal power plants, which are often co-located, with desalination plants, so that, all the discharge, from both the plants, can be easily pumped into the sea. Since, the world is running out of fresh water, we have to look for attentive source of water. In countries like India, the ground water is being exploited, for agricultural purpose, and the ground water is getting depleted. Depleting water resources is a threat to agriculture production. It is a vicious circle.

That is why, distributed energy systems, using Hydrogen as an alternative fuel,  is an important step, towards sustainability. One can generate Hydrogen from water, using renewable energy source, like solar or wind, and store them, for future usage. The stored Hydrogen can be used to generate power, as and when required, at any remote location (even where there is no grid power).The water is regenerated, during this process of power generation using Fuelcell, which can be recycled. There is no large consumption of water, and there is no greenhouse emission. It is a clean and sustainable solution. The same stored Hydrogen can also be used as a fuel for your car! Therefore; (The above statics are based on Wikipedia data).

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, because 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 on site 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 forms 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 changes 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 like 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.

 

We  acknowledge that solar energy is a potential renewable energy source of the future. The total energy need of the world is projected in the next 40 years to be 30 TW (terra watts) and only solar energy has a potential to meet the above demand. However, harnessing sun’s energy to its fullest potential is still a long way to go. Concentrated solar power (CSP) offers a greater hope to fill this gap. The main reason is the cost  advantage of CSP compared to PV solar and energy storage technologies and their costs.

The cost of PV solar has steadily decreased in the past few years. Though the cost of solar cell has come down to $0.75 per watt, the overall cost of the PV system is still around $ 3.00 per watt. This is due to the cost of encapsulation; interconnect wiring, mounting of panels, inverters and battery bank. The overall cost of the system will not come down drastically beyond a point. This makes PV solar still more expensive compared to conventional power generation using fossil fuels. People can understand the value of renewable energy and impending dangers of global warming due to greenhouse gases, but the final cost of energy will decide the future of energy sources.

In PV solar the sun’s light energy is directly converted into Electricity, but storing such energy using batteries have certain limitations. PV solar is suitable for small-scale operations but it may not be cost-effective for large-scale base load power generation. The best option will be to harness the sun’s thermal energy and store them and use them to generate power using the conventional and established methods such as steam or gas turbines. Once we generate thermal energy of required capacity then we have number of technologies to harness them into  useful forms. As we mentioned earlier, the thermal energy can trigger a chemical reaction such as formation of Ammonia by reaction between Hydrogen and Nitrogen under pressure, which will release a large amount of thermal energy by exothermic reaction. Such heat can be used to generate steam to run a stem turbine to generate power. The resulting ammonia can be split with concentrated solar power (CSP) into Hydrogen and Nitrogen and the above process can be repeated.

The same system can also be used to split commercial Ammonia into Hydrogen and Nitrogen. The resulting Hydrogen can be separated and stored under pressure. This Hydrogen can be used to fuel Fuel cell cars such as Honda FXC or to generate small-scale power for homes and offices.

By using CSP, there is potential of cost savings as much as 70% compared to PV solar system for the same capacity power generation on a larger scale. Focusing sun’s energy using large diameter parabolic troughs and concentrators, one can generate high temperatures.  Dishes can typically vary in size and configuration from a small diameter of perhaps 1 meter to much larger structures of a dozen or more meters in diameter.  Point focus dish concentrators are mounted on tracking systems that track the sun in two axes, directly pointing at the sun, and the receiver is attached to the dish at the focal point so that as the dish moves, the receiver moves with it.  These point focus systems can generate high temperatures exceeding 800ºC and even 1,800ºC.

The temperature required to run a steam turbine does not exceed 290C and it is quite possible to store thermal energy using mixture of molten salts with high Eutectic points and use them to generate steam. Such large-scale energy storage using lead-acid batteries and power generation using PV solar may not be economical. But it will be economical and technically feasible to harness solar thermal energy using CSP for large-scale base load power generation. It is estimated that the cost of such CSP will compete with traditional power generation using coal or oil in the near future.CSP has potential to generate cost-effective clean power as well as a fuel for transportation.

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 of gas turbine. The mechanical energy is converted into electricity in power generation and as a motive force in transportation. The fundamental principles remain the same irrespective of the efficiencies and sophistication 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 use 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 use 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 part 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 a 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 now 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.

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