In 1882 the first permanent commercial central power system became operative in Lower Manhattan.

1882 年，第一个永久性商业中央电力系统在曼哈顿下城投入使用。

They are so, even upon the principles of the commercial system.

他们是如此，即使是在商业系统的原则之上。

The most efficient solar cell yet still only converts 46% of the available sunlight to electricity, and most commercial systems are currently 15-20% efficient.

迄今为止最高效的太阳能电池也只能将阳光能量的46% 转化为电能，而目前大多数商业化的太阳能系统 只有15-20%的转化效率。

The prejudices established by the commercial system have taught us to believe, that national wealth arises more immediately from exportation than from production.

商业体系所建立的偏见让我们相信， 国家财富更多地直接来自出口而非生产。

But they have not yet come up with the $5 million that EPRI says will be needed to develop a commercial system, by making the lasers yet smaller and cheaper.

但他们尚未拿出 EPRI 所说的 500 万美元资金来开发商业系统，使激光器变得更小、更便宜。