太空利用太阳能

30多年来，梦想家就一直设想在太阳永远能照耀到的地方──太空中──利用太阳能。如果我们能在环绕地球的轨道上安置巨大的太阳能电池板，将其中哪怕是一小部分的可用能源传回地球，它们可以向地球上的任何地方提供不间断的电力。

SPACE-BASED SOLAR POWER

For more than three decades, visionaries have imagined tapping solar power where the sun always shines -- in space. If we could place giant solar panels in orbit around the Earth, and beam even a fraction of the available energy back to Earth, they could deliver nonstop electricity to any place on the planet.

这项技术听起来可能像是科幻小说，但其实很简单：在22,000英里之外的太阳能电池板将能源以微波的形式传回地球，然后转化为电力并进入到电网中。（低能量的光束被认为是安全的。）直径1英里的地面接收站可以提供约1,000兆瓦电力，足以供应平均约100万户美国家庭的使用。

The technology may sound like science fiction, but it's simple: Solar panels in orbit about 22,000 miles up beam energy in the form of microwaves to earth, where it's turned into electricity and plugged into the grid. (The low-powered beams are considered safe.) A ground receiving station a mile in diameter could deliver about 1,000 megawatts -- enough to power on average about one million U.S. homes.

将太阳能收集器送至太空的成本是最大的障碍，因此有必要设计重量足够轻，可以减少发射次数的系统。已经有些国家和公司希望最早在未来10年内提供这种太空电力。

The cost of sending solar collectors into space is the biggest obstacle, so it's necessary to design a system lightweight enough to require only a few launches. A handful of countries and companies aim to deliver space-based power as early as a decade from now.