But it is not enough for the US and European Union countries to improve their energy efficiency unless other countries do so as well. China and India can pursue security of supply by using their large coal resources, but unless they also have access to improved coal technology, the burdens they impose on the atmosphere will be large.
但是，除非其他国家也提高其能源效力，否则，美国和欧盟国家这样做是不够的。中国和印度可以通过利用其巨大的煤炭来源来寻求供应安全，但是，除非它们可以得到改进的煤炭技术，否则，它们带给大气的负担将会是巨大的。