20.—Energy in the Future—The Role of Nuclear Fission and Fusion

Abstract

SynopsisFor comfort the total future world population faces a limit. Three or more educated generations seem likely before the population growth will be checked. It seems prudent to envisage a world population of about 15 thousand million in a century or two. Their energy needs for food, water, warmth, clean air, locomotion and management of wastes may be assessed at 5 to 50 thermal kilowatts per capita. That amounts to 0·05 per cent, to 0·5 per cent, of the energy supply from the sun. Generating this amount by nuclear fission would cause no severe pressure on world resources of uranium and thorium for hundreds of centuries, if near-breeders such as CANDU reactors are used exploiting the uranium-thorium fuel cycle. Neither the cost of fuel supply nor of waste management to keep the environment unburdened by extra radioactivity need be as high as prices now paid for coal and oil. The addition of breeders or other means such as nuclear fusion or spallation for increasing the neutron supply would significantly lower the use of uranium and thorium but would not necessarily reduce the cost of power.