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Use of sources other than oil a myth?
B. LAKSHMINARAYANAN
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It is the most convenient energy available and all transport technologies are based on its use
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Many articles are being written nowadays on the need to achieve energy security for the country, with less emphasis on oil. While these articles appear very good on paper, the reality about the use of sources other than oil seems to have been buried. Every one talks about wind and solar energy, hydrogen, vegetable oils, etc. It is time to assess the realities.
We must first realise that oil is the most convenient energy available to mankind and all transport technologies are based on the use of oil and arguably the most powerful entity in the business world is the oil Industry. If you combine the two facts, you will see that the world economy is based largely on oil production and trade and that oil cannot be replaced in the near future. Let us look at some of the alternatives.
I remember that way back in the late 50s, we school students had been taken to the National Physical Laboratory, New Delhi, and there we were shown a prototype of a solar cooker. Fifty years later, I am still to see the solar cooker being used in households.
Cost and convenience
Cost, convention and convenience have a lot to do with these intended changes. Take wind energy. Tamil Nadu has been a pioneer in this field. But it is also true that wind power is intermittent, wind farms need 85 times more area to produce the same amount of energy as a conventional gas-fired power plant, residents complain about noise pollution and it costs much more than the electricity generated by fossil fuels. Also, wind power has had a devastating effect on bats and birds.
Solar energy is great. Even a minute fraction of what falls on the earth’s surface is more than enough to supply all our energy needs. In total, 122,000,000,000 MW is incident on the earth’s surface — a whopping ten thousand times more than our total energy requirements. The energy produced is clean and solar panels demand low maintenance.
But there are problems. The highest power output can be achieved at the equator with 1,020 watts per square metre. This rapidly falls off as one moves away from the equator. Solar cells for major heat and electricity generating projects require a significant surface area.
For example, a 20 MW Korean plant is expected to be 600,000 m2, or 80 football fields in size. The most efficient panels can covert 20 per cent of this energy into electricity which, if connected to the grid, must be converted from DC to AC, resulting in further power loss. If we factor in the cost of panels, the current shortage of refined silicon and the unreliability of the weather, solar panels start to look less attractive.
Tidal power harnesses the energy of large volumes of water moving in and out from the coast. Tides are extremely reliable and predictable, which is useful for power management. But tidal plants are very expensive and may not see adequate returns for years, due to high costs.
Jatropha plants are being mentioned as a solution for the production of bio-diesel. Can you imagine the amount of land that will be needed to harness even a small fraction of this energy?
In a country of a billion people, where every bit of land is more or less occupied and where wars are being waged not to let go off one’s land for any purpose, can one have an optimistic view? If millions of acres are needed for this, will it not replace some other produce which is being taken out of these lands? Hydroelectric energy poses similar problems.
A much better solution is to have a distributed system over an entire continent. When one county is producing excess electricity, it should be able to transfer the extra to someone else. The other problem is that everything we do at the moment in the area of alternative energy is essentially small scale.
In the same way that fossil fuels were acceptable when they were not used much, renewable sources can cause problems upon mass deployment. Too many wind farms could change air circulation in the atmosphere and therefore, weather patterns. Production of tidal and wind energy will affect currents and local ecosystems, too many solar panels would prevent a lot of light falling on the earth and from its being warmed, possibly causing cooling (global dimming).
Just as we did not know the effects mass use of fossil fuels would have on the earth’s systems, it is hard to predict exactly how the widespread use of renewable energy sources would affect the world around us. We must learn from our mistakes and tread carefully into the future.
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