For most of human history, the dominant concerns about energy have centered on the benefit side. Inadequacy of energy resources of the technologies for harvesting, converting, and distributing those resources has meant insufficient energy benefits to human beings and hence inconvenience, and constraints on its growth. The 1970’s, then, represented an turning point. Energy was seen to be getting costlier in all respects. It began to be believable that excessive energy costs could pose threats on a par with those of insufficient supply. It also became possible to think that expanding some forms of energy supply could create costs exceeding the benefits.
参考答案：人类历史发展长河中，人们主要关心的是能源有利的一面。能源资源不足，或者为开采、加工和分配这些资源所需技术的不足，会影响能源为人类带来利益，同时意味着能源的增长遭到干扰和限制。到了20世纪70年代，出现了一个转折点，能源的多方成本均显著增长。人们自然有理由认为，高昂的能源成本所带来的威胁，已同能源供应不足所产生的危险不相上下。同时，也有人担心，依靠扩大能源资源增加供应所需付出的代价，也许大于其所带来的利益。