LONDON We cannot afford to be complacent about the future energy supplies needed to maintain our current standards of living and economic growth. Nor can we be complacent about the environmental impact of current consumption levels of carbon fuels.

Oil accounts for the bulk of energy consumption in developed and developing countries. Oil reserves, insofar as they can be accurately estimated, suggest that the world should have adequate supplies for the first few decades of this century but probably not for the second half of the century.

Optimists say new supplies will be found and that it will become economical to develop sources that are difficult to access at present. Other observers fear that, unless we take much more effective conservation measures, we will jeopardize the livelihoods of our grandchildren, if not our children.