What America needs is an environmentally friendly, logistically feasible, and economically responsible alternative fuel source.

美国需要的是一种环保的，现实可行的，合理价位的可替换燃料能源。

youdao

VO: What America needs is an environmentally friendly, logistically feasible and economically responsible alternative fuel source.

美国需要的是一个保护生态环境的，逻辑上可行的，经济上可负担得起的替代能源的资源。

youdao

By far, the most promising alternative source of energy for cars is the hydrogen-based fuel-cell engine, which USES hydrogen to create electricity that, in turn, powers the car.

目前为止，氢燃料电池发动机是最有竞争力的汽车动力代替品。氢燃料电池发动机是用氢作燃料产生电能以充当汽车的动力。

youdao

The smallest of these chargers, which convert light into electricity, weighs just 4 ounces, has dimensions that are slightly larger than a sheet of paper, and can provide significant power to a soldier in the field without the need for an alternative fuel source.

ENGADGET: Alta Devices claims world's lightest, most efficient military solar chargers

What makes helium-3 so attractive as an alternative future fuel source is its environmentally friendly credentials, as it does not produce radioactive waste.

CNN: Mining the moon for a nuclear future