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Showing posts with label Clean renewable energy. Show all posts
Showing posts with label Clean renewable energy. 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.

Sunday, April 15, 2012

New Hydrogen atom- a source of cheap energy?

Hydrogen has been accepted as a source of clean energy for many reasons. Hydrogen can completely eliminate anthropic greenhouse gas emission into the atmosphere and stop global warming. It has high energy content than any other fossil fuels we are currently using, making it an efficient fuel. The combustion product of Hydrogen is only water which is recyclable. Many individuals, Governments and institutions around the world are trying develop cheaper methods of generating Hydrogen from various sources both renewable as well as non-renewable. The non-renewable sources are supposed to facilitate a smooth transition from fossil fuel economy to Hydrogen economy. However, all attempts to generate Hydrogen at a cost lower than the projected cost of $ 2.50 per kg by DOE has not been successful, even though many recent technologies are promising. Meanwhile massive investments are made on renewable energy sources including wind, solar and biological all over the world. Generating Hydrogen from water using Solid Polymer Membrane Electrolyzer is a known technology using renewable energy sources. One can easily deploy such systems for commercial applications even though it is currently expensive. Many individuals and institutions are also claiming ‘free energy’ sources with or without generating Hydrogen. In some cases researches are claiming an abnormal production of Hydrogen using ‘Cold Fusion’ or ‘Plasma electrolysis’ of water, as much as 800% more than the theoretical values. Some companies claim low energy consumption using photo- catalyst to generate Hydrogen using direct sunlight and water. Hydrogen generation using renewable sources is a distinct possibility to reduce the cost of Hydrogen in the long run. However, the world is in hurry to develop a cheap and sustainable method of Hydrogen generation without any greenhouse gas emissions. One US based company is claiming to have invented a new Hydrogen atom which has not been reported previously in the literature. According to the inventor, this new atom of Hydrogen is called ‘Hydrino’.He has presented a detailed theory called ‘Grand Unified Theory’ that predicts catalysts that allow energy to be extracted from lower energy state of Hydrogen atom. They have demonstrated the process using a proto type in the laboratory and their claims have been validated by an independent Laboratory after conducting trial runs and analyzing the results using spectrum analysis and other techniques. The process involves generation of Hydrogen by using electrolysis of water. The resulting Hydrogen is then reacted with a proprietary solid catalyst developed by the company. According to the company, “Since certain proprietary catalysts cause the hydrogen atoms to transition to lower-energy states by allowing their electrons to fall to smaller radii around the nucleus with a release of energy that is intermediate between chemical and nuclear energies, the primary application is as a new primary energy source. Specifically, energy is released as the electrons of hydrogen atoms are induced by a catalyst to transition to lower-energy levels (i.e. drop to lower base orbits around each atom's nucleus). The lower-energy atomic hydrogen product called "hydrino" reacts with another reactant supplied to the reaction cell to form a hydride ion bound to the other reactant to constitute a novel proprietary compound. Alternatively, two hydrinos react to form a very stable hydrogen-type molecule called molecular hydrino. Thus, rather than pollutants, the byproducts may have significant advanced technology applications based on their stability characteristics. For example, hydrino hydride ions having extraordinary binding energies may stabilize a cation (positively charged ion of a battery) in an extraordinarily high-oxidation state as the basis of a high-voltage battery. Further, significant applications exist for the corresponding molecular hydrino wherein the excited vibration-rotational levels could be the basis of a UV laser that could significantly advance photolithography and line-of-sight telecommunications. A plasma-producing cell based on the extraordinarily energetic Process has also been developed that may have commercial applications in chemical plasma processing and as a light source.” The company claims that an average generating capacity of a system will be 1000kw, with installed cost at $1000/kw with fuel cost at less than $0.001/kw with zero greenhouse emission.The solid catalyst is regenerated and recycled. The cost of Hydrogen from electrolysis becomes insignificant due to generation of large excess thermal energy, to generate power. The above claims are too attractive to ignore and it could be a game changer in the energy industry. The output energy is more than the theoretical values calculated, thus violating the Law of Thermodynamics. This excess energy is attributed to the presence of ‘Hydrino’. However, one has to be open to new ideas because science is ever-changing and even well-established theories and concepts are challenged as Science evolves with new discoveries and inventions.

Tuesday, March 6, 2012

Hydrogen assisted combustion

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 substantial 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 electromagnestism, which opened the way for electricity generation as well as transportation. In both these industries, the key component 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 been carrying 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 substantial in order 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 individual industries, 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 examine carefully there are not many alternative fuel sources except Hydrogen that could meet these parameters. 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 Malaysis, 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 reduce fossil fuels by blending with Hydrogen to the maximum extent possible so that we can achieve two objectives. We can reduce the carbon emission and at the same we can deploy Hydrogen as a blended fuel with fossil fuel rather than pure Hydrogen. Since Hydrogen is a very light gas and readily form 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 reduce 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.

Saturday, February 18, 2012

Hydrogen-the key to sustainability

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 for example, a minimum wind velocity of 3mts/sec for certain number of hours, while designing a wind based energy system. The same principle applies to solar energy and we need certain minimum solar intensity and number of 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 whenever the intermittent power flows from wind or sun. They can operate from a wide 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 reduce 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.

Friday, February 10, 2012

Water and Energy

Water and Energy, are two sides of the same coin. It is known, from the famous equation E=mc2, 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 used, to split water, into Hydrogen and Oxygen, is higher, compared to the amount of energy, that can be generated, from the resulting Hydrogen, using Fuel cell. But, this problem can be mitigated, by using renewable source of energy, such as PV solar, Solar (thermal), wind energy, geothermal energy, ocean thermal energy conversion (OTEC) etc.The cost of renewable energy, is still considered expensive, for two reasons. We are used to cheap energy, from fossil fuels, for decades, and most of the investments, made on fossil fuel infrastructures, have been already realized. 2. A complete switch over, to renewable energy technologies, will require massive new investment.Unlike, investments made on fossil fuel infrastructures, over several decades, the investment required, for renewable energy infrastructure, is not only massive, but needs to be deployed, in a shorter span of time, simultaneously all over the world. There is no basic infrastructure in renewable energy industry, in existence, to make this change. Meanwhile, the unabated emission of carbon dioxide, by fossil fuels, is certainly, 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 is 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 skeptics 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. ‘Clean Energy and Water Technologies’, is working, both on water and energy technologies, to make Hydrogen future, a reality. To start with, all existing fossil fuel infrastructures can be modified towards Hydrogen generation, and fuel cell based power 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, 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, using renewable energy source, and ‘Bio-hydrogen’ using biotechnology from waste organic matter. The future generation will not only have a cleaner and affordable fuel, but a more sustainable future!