A political leader wanted to know recently whether the windmills in the districts of Satara and Sangli in Maharashtra have reduced the rainfall in that region. “Can such a thing happen?” he asked and wanted me to look at the subject more closely. So are we doing something unusual in using wind turbines? My answer is “No!” For thousands of years, wind energy has been exploited. In Denmark, for instance, windmills have been generating electricity since 1890. Both Denmark and Hungary have successfully operated 200 kilowatt (kw) machines continuously for long periods. In 1941, the United States installed a 1.25 mw (1 mw = 1000 kw) wind powered generator on a hill near Rutland, Vermont, and operated it for years before a mechanical failure brought its use to an end. That’s history. But today Germany, Denmark and Spain — small countries when compared to India — have been producing electricity by wind power in a grid-connected mode on a vastly larger scale than we do. To be specific, Europe’s present installed wind power capacity is 19,800 mw (Germany: 10200 mw; Spain: 4000 mw; Denmark: 2450 mw). The United States, the second largest wind power generator after Germany, has an installed capacity of 4400 mw, which is 3.5 times as large as India’s 1267 mw. Today, the wind power industry is quite formidable, employing about 70,000 people and is worth Rs 250,000 million. But no country in Europe nor the United States has ever reported that wind turbines had had an adverse effect on rainfall patterns or the climate. Indeed, having discounted any such connection, they now have large national wind energy programmes, growing at a rate of 40 per cent annually, and have let the wind turbine size grow from a 55 kw to the now operational commercial machine of 2500 kw. Not only that, they have developed prototypes of 4500 kw turbines which may soon become commercially viable. Undoubtedly, the cost of wind power is high, compared to that of hydroelectric or thermal power. But the cost differential is narrowing. By 2010, the unit price of wind power is expected to fall from the present 3.61 US cents to 2.62, with the capital costs declining from the present US $765 per kw to $555. That’s why the West is investing massively in the wind power programmes and viewing them as an investment in the future for cost effective inexhaustible energy. The West, which is so fastidious about long-term environmental impact of any energy programme, will obviously not have allowed the wind energy programme develop the way it did if the windmills were going to affect the rains. I am reminded of one case. William E. Heronemus, of the University of Massachusetts, had made a proposal some 30 years ago in which he estimated that 300,000 wind turbines stretching in a band from Texas to North Dakota could generate 189,000 mw of power. He envisaged that each tower would support 20 turbines in a 270 metre high structure. The project was considered absolutely sound and feasible technically, but was abandoned not because Heronemus’s gigantic machines were feared to interfere with the weather but because it was thought that they, in such a large number, might make the majestic mountains look ugly! Modern wind turbines are highly sophisticated machines built on aerodynamic principles developed from aerospace industry, using electronics and advanced materials, and are designed to deliver energy across a range of wind speeds. One can demonstrate, scientifically, that the monsoon process is unaffected by the operation of these machines. However, for the purpose of this piece, I prefer not to go into the theory of the monsoon or the mechanism of rain making in view of a well-known law in physics. The law says that while what is proved theoretically may not always be proved experimentally, what is proved experimentally can always be proved theoretically. Today, over 56,000 wind turbines, generating 27,000 mw of electric power for around 14 million households in 45 countries, have already shown experimentally that these giant machines can, and indeed do, run continuously for long periods without affecting the rains or the weather. When you can see something like this with your naked eye, you don’t use spectacles — they would only distort the vision! I for one would plead for completing all energy related programmes — including those concerning windmills — expeditiously and without unjustified controversies. The reason is obvious. Energy is a basic natural resource. It plays a crucial role in creating wealth for everybody. What was once a matter of choice to be made from various options of energy has now become a matter of compulsion and nations are forced to exploit practically all the options they have. The advanced world has unanimously embraced from its experience wind power energy as a preferred option. That India cannot afford to be without the full spectrum of energy options being available for exploitation — including that of wind power — is, in short, my general thesis. Remember, solar radiation is man’s greatest resource. It heats the earth’s surface, drives the rains, winds, atmospheric and oceanic circulations and convections, and provides the energy for every form of life cycle through photosynthesis. The challenge lies in the fact that while the total power continually radiated from the sun and intercepted by the earth is 173,000 billion kw, the power used by the world is only about 6. That shows the magnitude of the challenge at the global level. But, I would like to be not global but parochial. If somebody were to ask me to name just one programme to ultimately improve the lot of India’s poorest of the poor, I would say create a power surplus in the country and keep it that way in time to come. I believe that the first part is possible to be achieved within five years, if we steadfastly complete all the power-related projects already in hand and avoid controversies of the kind just raised with regard to our wind energy programmes. The writer, a former scientific adviser to the prime minister, is presently member, Consultative Group of Eminent Senior Scientists (GOI)
