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There is a raging debate going on around the world especially in US about the global warming and its causes, among scientists and the public alike. When IPCC released its findings on the connection between greenhouse gas emission and the global warming and its disastrous consequences, there was an overwhelming disbelief and skepticism in many people. In fact many scientists are skeptical even now   about these findings and many of them published their own theories and models to prove their skepticism with elaborate ‘scientific explanations’.   I am not going into details whether greenhouse gas emission induced by human beings causes the globe to warm or not, but certainly we have emitted billions of  tons of Carbon in the form of Carbon dioxide into the atmosphere since industrial revolution. Bulk of these emissions is from power plants fueled by Coal, oil and gas. Why power plants emit so much Carbon into the atmosphere and why Governments around the world allow it in the first place?  When the emission of Oxide of Nitrogen and Sulfur are restricted by EPA why they did not restrict Oxides of carbon? The reason is very simple. They did not have a technology to generate heat without combustion and they did not have a technology to generate power without heat. It was the dawn of industrial revolution and steam engines were introduced using coal as a fuel. The discovery of steam engines was so great and nobody was disturbed by the black smoke it emitted. They knew very well that the efficiency of a steam engine was low as shown by Carnot cycle, yet steam engine was a new discovery and Governments were willing to condone Carbon emission. Governments were happy with steam engine because it could transport millions of people and goods in bulk across the country and Carbon emission was not at all an issue. Moreover carbon emission did not cause any problem like emission of oxides of Sulfur because it was odorless, colorless and it was emitted above the ground level away from human beings. However the effect of Carbon is insidious. Similarly, power generation technology was developed by converting thermal energy into electrical energy with a maximum efficiency of 33%.This means only 33% of the thermal energy released by combustion of coal is converted into electricity. When the resulting electricity is transmitted across thousands of kilometers by high tension grids, further 5-10% power is lost in the transmission. When the high tension power is stepped down through sub stations to lower voltage such as 100/200/400V further 5% power is lost. The net power received by a consumer is only 28% of the heat value of the fuel in the form of electricity. The balance 67% of heat along with Greenhouse gases from the combustion of coal is simply vented out into the atmosphere. It is the most inefficient method to generate power. Any environmental pollution is the direct result of inefficiency of the technology. Governments and EPA around the world ignore this fact .Thank to President Obama who finally introduced the pollution control bill for power plants after 212 years of industrial revolution.  Still this bill did not go far enough to control Carbon emission in its current form. Instead of arguing whether globe is warming due to emission of Carbon by human beings or not, Scientists should focus on improving the science and technology of power generation. For example, the electrical efficiency of a Fuel cell is more than 55% compared to conventional power generation and emits reduced or no carbon. Recent research by MIT shows that such conversion of heat into electricity can be achieved up to 90% compared to current levels of 35%.Had we developed such a technology earlier, probably we will not be discussing about GHG and global warming now. MIT research group is now focusing on developing new type of PV and according to their press release: “Thermal to electric energy conversion with thermophotovoltaics relies on radiation emitted by a hot body, which limits the power per unit area to that of a blackbody. Micro gap thermophotovoltaics take advantage of evanescent waves to obtain higher throughput, with the power per unit area limited by the internal blackbody, which is n2 higher. We propose that even higher power per unit area can be achieved by taking advantage of thermal fluctuations in the near-surface electric fields. For this, we require a converter that couples to dipoles on the hot side, transferring excitation to promote carriers on the cold side which can be used to drive an electrical load. We analyze the simplest implementation of the scheme, in which excitation transfer occurs between matched quantum dots. Next, we examine thermal to electric conversion with a glossy dielectric (aluminum oxide) hot-side surface layer. We show that the throughput power per unit active area can exceed the n2 blackbody limit with this kind of converter. With the use of small quantum dots, the scheme becomes very efficient theoretically, but will require advances in technology to fabricate.” Ref:J.Appl.Phys. 106,094315c(2009); http://dx.doi.org/10.1063/1.3257402 Quantum-coupled single-electron thermal to electric conversion scheme”. Power generation and distribution using renewable energy sources and using Hydrogen as an alternative fuel is now emerging. Distributed energy systems may replace centralized power plants in the future due to frequent grid failures as we have seen recently in India. Most of the ‘black outs’ are caused  by grid failures due to cyclones, tornadoes and other weather related issues, and localized distribution system with combined heat and power offers a better alternative. For those who are skeptical about global warming caused by man-made greenhouse gases the question still remains, “What happened to billions of tons of Caron dioxide emitted into  the atmosphere by power plants and transportation  since industrial revolution?”.          

Photovoltaic  solar industry has started expanding in recent years in US and Europe and the rest of the world also started following. Still solar energy is considered expensive in many parts of the world for various reasons. In most of these countries, energy is predominantly managed by Governments with age-old technologies and transmission systems. Coal is still the major fuel used for power generation and distribution and their infrastructures are old and inefficient. Transmission losses, power pilfering, subsidized power tariffs and even free power for farmers, are some of the issues that compounds the problems. Energy and water are considered more of social issues rather than business issues. For example in India, frequent power failures are common  and sometimes people do not have power even up to 8 to 12 hours  a day, especially  in country sides. Standby diesel generators are integral part of an industry or business. The heavily subsidized power supply by Government from coal-fired power plants is  underrated. The average power tariff in India is still less than $0.07/kwhr.But the reality is they will be using diesel generated power for equal several hours in a day  and the cost of diesel power varies from  $0.24 up to $0.36/kwhrs, almost in par with solar power. The average power cost will amount to $0.18 to $0.20 /kwhrs.

Any slight increase  in oil price will have a dramatic effect in energy cost in India and their balance of payment situation.Governments are in a precarious situation and they have to make a balancing act between subsidizing the energy cost and winning the elections. They often subsidize the power resulting in heavy revenue losses for Government run electricity boards. Most of the electricity boards in India are in red. People are used to low power tariffs for several decades and any increase in the tariff will make the Government unpopular. Greenhouse effect and global warming are secondary issues. With an average economic growth rate at 7% year after year, their energy requirements have gone up substantially. They may need several hundred thousands of MW power in the next 5 to 10 years. They have opened up energy sector to private only in recent years.

Renewable energy industry is relatively new and there are very few large commercial-scale solar and wind power plants in India. Majority of residents and businesses cannot afford high cost of PV solar installation. Even if they install, there is no ‘power- in tariff’ mechanism by Government where consumers can export surplus energy at a higher tariff to the grid. With current power failures lasting 8-12 hours/day, such mechanisms will have no value. The situation is the same in many Asian countries.

The solar panel costs are high due to lack of local production of silicon wafers, batteries and inverters and most of them are still imported. State electricity boards do not have funds to buy power at higher tariffs. Import duties and taxes on imported components are still high making renewable industries uncompetitive against cheap coal-fired,  subsidized power cost of $0.07/kwhrs .India requires massive investment on renewable energy industries. But most of the power projects which are under planning stage or under implementation are based on either coal or oil or LNG.There is no sign that India will soon become a major player in renewable energy.

In PV solar projects, the cost of storage batteries are higher than the solar panel during the life cycle of 25 years. If the life of a battery is 8 years then you will need 3 batteries during the life cycle. For example, if you use 100 watts solar panel with a life span of 20 years, the initial cost of solar panel may be $300 which will generate an average power of 140 watt.hrs /day. If you plan to store 5 days energy using a battery, you will enquire 5x 140= 700 watt.hrs battery, costing about $175.If you have to replace batteries 3 times during the life span of 20 years then the cost of battery is 3×175= $525.You have to add operation and maintenance cost, in addition to it. Therefore, your investment on batteries is 1.75 times more than solar panels. This cost will substantially add up to your energy cost.

In most of the Asian countries where they cannot export surplus power to the grid, they have to rely only on batteries. This high cost of stored energy is not remunerative because they cannot export this surplus to the grid at a higher tariff. This situation is not likely to change at least in the short-term.

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.

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