During the prolonged agitation against the proposed Kudankulam Nuclear Power Project in Tamil Nadu, it was suggested that we should explore all alternatives to nuclear power that may be feasible.
India does not possess large deposits of one alternative, natural gas. Our largest discovery, in the Krishna-Godavari basin, is yielding far less gas than expected earlier. The first preference for use of natural gas is as a feedstock for producing fertilisers or petrochemicals. The second priority would be as compressed natural gas (CNG) as fuel for city buses and taxis. Krishna-Godavari gas will thus not be available for power generation in South India. Gas available in the Kaveri basin is very limited in quantity and is now supporting a small generation capacity. The only gas in South India can be liquefied natural gas (LNG) imported from the Middle East, Australia, Indonesia or Malaysia. The international price of LNG is indexed to the price of crude oil, and is presently $8-9/million BTU. At this price, gas based power will be Rs 6 or more per kWh — more than twice the cost of power from Kudankulam.
Some people favour developing more wind power. We are now installing wind turbines with an output of 2.5 Mw. To replace the two 1000-Mw Kudankulam units, we will need 800 units of 2.5 Mw size. This will require a very large land area, apart from a large investment. We must note that wind is available only 20-25 per cent of the time. So we will need some other form of electricity generation, as a backup, when wind does not blow.
India is endowed with a lot of sunshine. Unfortunately solar energy is, on the other hand, available only in a diffused manner. The largest solar photo voltaic power plant in the world is less than 100 Mw in capacity; the cost of solar power is about Rs 20 per kWh. Solar cells available today have an efficiency of less than 15 per cent, and hence large collecting surfaces are necessary. Competitive designs may not be commercially available for 10-20 years.
What about the hydro-electric option? The southern states have very little hydro potential available. What is left will involve the submergence of tropical rain forests — areas with rich biodiversity. What we can do, however, is to convert some of the storage-type hydro-power units to pumped-storage hydro-power, using reversible pump-turbines to provide peaking power — provided base load power, coal- or nuclear-generated, is adequately available.
Let us now discuss the role of coal. We produce some 55-60 per cent of our electricity from coal. Indian coal has a high ash content and low heat value. Coal stations in south India have to get coal transported over a long rail route, as coastal shipping of coal is relatively undeveloped. In the past few months, supply to south India has been hit by social or political agitations and flooding of coal mines in Orissa.
India produces about 400 million tonnes of coal. Our demand is increasing, but increasing production is difficult; new coal mining areas are largely in India’s forested areas. We now import coal for use in power stations from Australia, Indonesia and South Africa. Imported coal costs two or three times more. As we import more coal, our coal-fired stations will produce more expensive power than now.
While in the near term India has to increasingly depend on coal-based power, this will make it difficult to reduce its carbon emissions. A little-known fact about coal-based power is that fly ash from these stations also spreads radioactivity; coal often has some uranium bearing rocks mixed in it. Furthermore, black-lung disease among coal miners and accidents in coal mines contribute to a high adverse health impact for coal, when calculated on a per-kWh basis. In fact, nuclear power comes out much better in such comparisons.
Now let’s look at the nuclear option. There are about 430 nuclear power units in operation in different parts of the world. The accident at Three Mile Island in the US in 1979 did not result in any fatality or escape of radiation to the environment. But the utility concerned suffered a huge financial loss. The Chernobyl accident in 1986 in present-day Ukraine resulted in some deaths among the plant operators and fire-fighters. A nearby town housing the plant personnel was evacuated completely and remains unoccupied. Many lessons were learnt from these two accidents and the industry set up the World Association of Nuclear Operators (WANO) to freely exchange all operational experience. This resulted in greatly enhanced safety and reliability for the world’s nuclear plants.
The Fukushima disaster happened because of an unusual combination of a very high intensity earthquake and a severe tsunami. These natural forces combined with the inadequacies of a design from an earlier time (the 1960s) resulted in the very serious partial meltdown of three reactors.
Following the Fukushima accident, Prime Minister Manmohan Singh ordered a safety review of all nuclear units operating in India. The results of these reviews have been placed in the public domain. WANO carried out a peer review of Kudankulam and is satisfied about the design provisions, quality of workmanship and the competence of our operations and maintenance personnel.
When the southern region as a whole is suffering from an acute shortage of power, the delay in the start-up of Kudankulam based on imaginary fears has been most unfortunate. The country should place its confidence on its nuclear engineers and scientists who have demonstrated their competence by operating 20 nuclear power units, the earliest two of which have been safely in service for over 40 years. What we should ensure is that our nuclear power units are built to the highest standards of safety and operated in the best possible manner.
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