Supplying energy in 1970 required the harvesting, processing and combustion of some three billion metric tons of coal, some 17 billion barrels of oil, more than a trillion cubic meters of natural gas and perhaps two billion cubic meters of fuel wood. It entailed the use of dirty coal as well as clean; undersea oil as well as terrestrial; deep gas as well as shallow; mediocre hydroelectric sites as well as good ones; and deforestation as well as sustainable fuel wood harvesting. Except for the huge pool of oil underlying the Middle East, the cheapest oil and gas are already gone. Some scientists believe there is a lot more to be found. But even if a few more giant oil fields are discovered, they will make little difference, against consumption on today’s scale. Oil and gas will have to come increasingly as imports from countries with very unstable economic conditions. There are a variety of other energy resources that are more abundant than oil and gas. Coal, solar energy, wind energy, and fission and fusion fuels are the most important ones. But they all require elaborate and expensive transformation into electricity or liquid fuels in order to meet society’s need None has very good prospects for delivering large quantities of electricity at costs comparable to those of the cheap coal-fired and hydropower plants of the 1960’s. It appears, then, that expensive energy is a permanent condition, even without allowing for its environmental costs. 71~ Except for the huge pool of oil underlying the Middle East,/the cheapest oil and gas arc alrcaci5 gone. Some scientists believe there is a lot more to be found. But even if a few more giant oil fields are discovered, they will make little difference against consumption on today’s scale. Oil and gas will have to come increasingly as imports from countries with very unstable economic conditions. There are a variety of other energy resources that are more abundant than oil and gas. Coal, solar energy, wind energy, and fission and fusion fuels are the most important ones. But they all require elaborate and expensive transformation into electricity or liquid fuels in order to meet society’s need. They may never be capable of delivering large quantities of electricity at costs comparable to those of the cheap coal-fired and hydropower plants of the 1960’s. It appears, then, that expensive energy is a permanent condition, even without allowing for its environmental costs.