抄録
It should be noted that the mother earth is limited and our resent civilization which is supported by cheap abundant oil is about to end. Unable to perceive this "Oil peak", Japan has been wasting a large amount of money, e.g. for infrastructures for motor vehicles. [Oil peak] essentially means that oil supply falls behind demand. Actually, about half of recoverable reserves have been used up, and now world oil discovery is about one fifth production. [Oil peak] also means [peak civilization]. The author has proposed the energy-profit ratio (EPR) as an important measure for evaluation of energies. We should abandon present wasteful civilization.