In fact, as early as the first oil crisis in the 1970s, when all nations felt the frightening effects of a shortfall of energy, they consequently rushed to find alternative energy sources.
其實，早在一九七○年代出現第一次石油危機，世界各國都感受到能源短缺的可怕後果，於是紛紛設法找尋替代的能源，高效率的電能當然首先中選。