Let's take a closer look in the United States.
让我们来看看美国。
Over the last couple of years -- really 2013, 2014 -- we prematurely retired four nuclear power plants.
在过去的几年里，尤其是2013、14年，我们过早报废了四个核电站。
They were almost entirely replaced with fossil fuels,
它们的发电量几乎全部被化石燃料发电取代了，
and so the consequence was that we wiped out almost as much clean energy electricity that we get from solar.
所以结果就是我们放弃了几乎和太阳能发电量相当的清洁能源。
And it's not unique to us. People think of California as a clean energy and climate leader,
而且我们在这件事上并不唯一。人们认为加州是使用清洁能源和保护环境的先锋州，
but when we looked at the data, what we found is that, in fact,
但是当我们查看数据，我们发现，事实上，
California reduced emissions more slowly than the national average, between 2000 and 2015.
在2000到2015年间，加州的减排速度是低于全国速度的。
What about Germany? They're doing a lot of clean energy.
德国的情况又怎样呢？德国人在使用很多清洁能源。
But when you look at the data, German emissions have actually been going up since 2009,
但是当你查看数据时，会发现德国的排放量自09年开始就持续升高，
and there's really not anybody who's going to tell you that they're going to meet their climate commitments in 2020.
而且一定没有人会告诉你，他们计划在2020年实现他们的气候承诺。
The reason isn't hard to understand. Solar and wind provide power about 10 to 20 percent of the time,
原因并不难理解。现在太阳能和风能提供了大概10%到20%的电力，
which means that when the sun's not shining, the wind's not blowing,
这意味着当阴雨连绵，风平浪静的时候，
you still need power for your hospitals, your homes, your cities, your factories.
你依旧需要给医院、家庭、城市、工厂提供电力。
And while batteries have made some really cool improvements lately,
虽然近来电池领域有了些巨大发展，
the truth is, they're just never going to be as efficient as the electrical grid.
但真相是，它们永远做不到输电网那样的高效率。
Every time you put electricity into a battery and take it out, you lose about 20 to 40 percent of the power.
每当你把电输入电池并使用它，你都会丢失20%到40%的电量。
