The Tarapur nuclear power plant

New Delhi, Sept. 30: Sudhinder Thakur, a nuclear power executive in Mumbai, fishes out a slide as he defends the future of nuclear power. The slide shows how 28kg uranium can generate the same amount of electricity as 700,000kg coal.

At a time India appears po-ised for unprecedented expansion of nuclear power —through its home-grown reactors and, perhaps, imported reactors — questions over nuclear economics have intensified.

India has 17 nuclear reactors feeding electricity to the nation that have been established over four decades through a programme that, critics say, has been dogged by delays and cost overruns.

The target was once 10,000MW by the year 2000 — 10 per cent of electricity output. But nuclear capacity today is 4,120MW, just 3 per cent of the total installed capacity.

“We’re building reactors faster now,” says Thakur, executive director, corporate planning, with the Nuclear Power Corporation. “The time from design to commercial electricity generation has shrunk from eight to five years.”

Five reactors are under construction. And the NPC hopes to build eight more indigenous pressurised heavy water reactors and — if possible — 10 imported reactors in the next 12 years.

Nuclear electricity tariffs range from 95 paise per unit of electricity from the first Tarapur reactor set up in 1969 to Rs 2.73 per unit from the latest 540MW reactors at Tarapur that began operations last year.

But experts say that nuclear power in India enjoys subsidies. The NPC leases heavy water from the department of atomic energy for its pressurised heavy water reactors.

“Nuclear energy is unlikely to be competitive if the true cost of heavy water is used to calculate the electricity costs,” says M.V. Ramana, a senior fellow at the Centre for Interdisciplinary Studies in Environment and Development, a private institution engaged in debates over the national electricity policy.

“The production cost of heavy water is higher than the price that the NPC pays for it.”

But NPC officials and nuclear scientists dismiss the claim, saying heavy water prices are indeed taken into account in nuclear electricity pricing. They say Ramana’s calculations are based on “wrong and invalid assumptions”.

“Capital costs of nuclear power are 30 per cent higher than coal-based thermal power, but fuel costs are lower — and nuclear power is far less sensitive to fuel price fluctuations,” says Thakur.

Ramana also predicts that future nuclear power will cost even higher. India’s first-stage reactors make plutonium fuel for the second-stage breeder reactors.

“When the cost of plutonium production, fuel fabrication and reprocessing are included, the cost of electricity from breeder reactors will be higher than the cost of electricity from the first-stage reactors,” says Ramana.

But scientists engaged in the fast breeder programme say there is a “global convergence” of opinion based on years of experience that breeder reactors will be economical.

“Electricity from India’s first 500MW fast breeder will cost Rs 3.22 per unit,” says Baldev Raj, director of the Indira Gandhi Centre for Atomic Research near Chennai.

“This is a real figure. It’s not based on a paper design. We’re halfway through construction,” says Raj.