而且，卡尔加里大学能源和环境系统小组的负责人大卫·基思说，要这么做很容易。
What's more, says David Keith who directs the University of Calgary's Energy and Environmental Systems Group, it would be pretty easy to do.
根据美国环境署资料，高铁和汽车或者飞机相比每公里使用能源最少，而一个全国范围的系统将能每年减少使用1.25亿桶的石油。
According to Environment America, high-speed rail USES a third less energy per mile than auto or air travel, and a nationwide system could reduce oil use by 125 million bbl. a year.
随着人们对现代建筑室内环境质量和能源消耗要求的不断提高，供热、通风和空气调节系统变得越来越复杂。
With the increasing demands on indoor environment quality and energy consumption in modern buildings, heating, ventilation, air-conditioning systems become more and more complex.
应用推荐