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Solar power is the only viable alternative

  • 29/11/1993

I understand you have an alternative to the Sardar Sarovar irrigation project, for using Narmada water. Can you give us an outline?
The alternative is to use exogenous water judiciously to supplement local water. There are two reasons why we cannot rely only on local resources. In a drought-prone area, the land is degraded, groundwater depleted and the biomass reserves carried over from year to year severely undermined. Consequently, traditional ways of coping with water scarcity by using local resources become practically useless. In north Gujarat, because of the variations in rainfall, there is no supplementary water to stabilise the production of the ecosystem. Unlike in the past, we can no longer manage with local resources; we have to supplement them to meet the needs of a larger population.

How do you propose to do this?
We will use Narmada water by spreading it over a wider area. In turn, we will require more energy because energy input depends on the area served. We want to make a series of canals that will extend all the way from Narmada to Kutch, Saurashtra and Banaskantha at the far end of north Gujarat. There are also losses, caused by distances, for which we have to account. To carry water over 500 km, one has to lift it through a height of 50 m, which involves energy. And how does one get the energy to lift this water? You have water available in the Narmada. We see no reason to reduce the 11.1 billion cum awarded to Gujarat by the Centre. It is evident that most areas in Madhya Pradesh get good rainfall and so, because the state hardly uses the water it has, it will need little more than 7.4 billion cum.

The real question is, where do you lift the water, where do you divert it? If the dam is built only to a height of 80 m, submergence is avoidable. And we can establish that with a dam height of 80 m and water flowing down the river, we can generate more than 700 MW. Gujarat"s share of 16 per cent will give us 120 MW. Also, with optimum external water, we can serve an area of anywhere between 3-41/2 million ha with only 4.9 billion cum.

This is an agenda that involves more efficient use of water, a larger service area and maintenance of the energy balance.

But Gujarat does not seem ready to accept "outside" suggestions these days.
This is not a prescription for Gujarat, but part of a wider agenda for reform of water and energy systems in the country, especially drought-prone areas. A common principle is integrating local and external energy and materials. Just as we integrate water from the outside system with local water, we also plan to integrate local energy production with external larger energy production. That is a key to the alternative.

India"s energy crisis can thus be addressed simply. There is no way we will ever attain energy self-reliance if we do not make a concerted effort to switch to the most important and widely available energy source -- the sun. In terms of Gujarat and Narmada, what comes out clearly is that if we have this service area of 41/2 million ha (and we are talking of servicing 3 million families, or about 15 million people), and if they develop the bioresource and use it wisely, there is no reason why a family should not be able to allocate two tonnes of biofuel a year for energy production, over and above their subsistence needs for fodder, food and fuel.

How will this be done?
Through various forms of low external input production that will minimise chemical inputs into agriculture. From what is known now about low external input sustainable agriculture and horticultural techniques for biomass production to replace petrochemicals, each family can easily produce an average of two tonnes of fuel biomass each year. We may not get the highest yields in a single plot, but the question is how to optimise the inputs to maximise the total yield in an area.

Many of the big problems about solar energy arose because people were always considering solar energy in isolation. The moment you integrate solar energy with other resources, the picture changes.

Going by the work done in Israel and California, in north Gujarat, where you have sufficient sun for at least 270 days in a year, you can produce enough heat energy to replace 250 kg of coal per year from an optimum solar system, which requires an area of about 11/2 square m and an investment of about Rs 1,000. This is enough self-reliance -- based on parameters established by technologists -- to make solar energy systems viable and widely acceptable.

How will this be financed?
If concessional finance is available at appropriate terms, energy prices will definitely be lower in the long run than the current prices for coal, provided the rates are adjusted for inflation. As everyone knows, coal is underpriced and enjoys tremendous externalisation of costs. The conclusion from studies on control of emissions is that coal prices should be at least double if they are to reflect the true cost.

Leave that aside for the moment, even with the current prices of coal, if they continue to be adjusted for inflation, I"m prepared to prove that if I get an investment at 4 per cent rate of interest, solar thermal energy production will be a very viable programme. These favourable credit rates should definitely be forthcoming; our policy should be that an environmentally desirable, equitable and dispersed production system should qualify for subsidised finance.

For a long time, solar energy was not workable because on cloudy days -- 90 or more days a year -- production stops. But a combined energy system can overcome this problem. Hydropower (or hydropower combined with a small amount of gas or fossil energy) can be very well integrated with solar power.

The right place for hydropower is where water flows down the river with little requirement for storage. You don"t require an enormous reservoir capacity. You can produce the same amount of energy because it is determined by the volume of water and the height over which it falls. So you have a choice. You can store the water and use it all year long, with solar energy as the main energy source, supplemented by biofuels. Or you can use hydropower. In other words, you have the solar to take care of the sunny days, and the hydro to take care of the monsoon days, and if you run short of both, you can use natural gas, which is the cleanest source of fossil energy we have today.

At present in Gujarat almost 85 per cent of the energy used is thermal -- coal and gas. In the alternate scenario, gas would be 20 per cent, hydro may be about 15 per cent, and the balance is solar and biofuel.

You are suggesting this will also provide a dispersed alternative to centralised and bureaucratically controlled production systems?
The main part will be dispersed. Given our three million families, even one KW installation per family, which is not affluence but energy for basic domestic and industrial needs, gives over 2,500 MW of power. The present Narmada scheme is capable of producing only about 1,000 MW.

With a dam of a height not much more than what has already been built, we can produce from the integrated solar-biofuel-hydro system at least 2,500 MW. So, the alternative provides more energy and more irrigation service, in a more sustainable and decentralised production system.

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