Underscoring the urgency in signing the nuclear deal with the US, Atomic Energy Commission chairman Anil Kakodkar has said that this was an opportunity to bridge the future energy gap without compromising on the country's principles and if it failed to do so, 'history will not forgive'.

Delivering a public lecture on 'Evolving Indian nuclear programme: Rationale and perspectives' organised by Indian Academy of Sciences in Bangalore on Friday, he said the currently-known uranium resources in the country were enough for setting up nearly 10,000 MWe installed capacity pressurised heavy water reactors and the country will need to import nuclear reactors and the fuel to achieve energy security.

"Our resources of uranium will last 40 years. Economic projections made by the Department of Atomic Energy indicate that without importing nuclear reactors or fuel, by the year 2050, the gap of installed capacity will amount to 412 GWe or 412,000 MWe," he said.

This would progressively increase in the subsequent decades till the growth in nuclear capacity eventually catches up as the country is bound to go through a huge economic growth. In this context, energy security becomes important and the country would have to get the energy from somewhere.

The best option was using the spent fuel as this was the biggest advantage of the nuclear fuel.

Import of coal needed to bridge future energy deficit, even if it could be affordable, will not only put huge burden on environment, but also enhance the country's vulnerability to supply shocks, he said.