So, I've invited Audrey Quinn from NPR's Planet Money team

所以我邀請了 NPR 的 Audrey Quinn

to help explain what's going on with my super-hot laptop charger.

來解釋一下為什麼我們的充電器會變得這麼熱。

So, Audrey, what's the deal?

所以，Audrey，這是為什麼呢？

Yeah. The first thing you have to understand is that the kind of power that comes out of your wall is actually different than the kind of power that your electronics want.

首先你必須要了解從牆上的插座出來的電和你的電子產品所需要的電是不同的。

It comes out in the form of alternating current electricity,

插座所提供的電是交流電，

that means the electrons are pulsing back and forth.

也就是說電子會來回跳動。

And your electronics want what's called direct current power, that's where the electrons are flowing straight like a river.

然而你的電子產品只接受直流電，意思就是電子像一條河一樣直直的流動。

So, they have to convert it.

因此要經過轉換才能用。

And when they do that conversion energy is wasted, so what you're feeling is energy lost in the form of heat.

當進行轉換時，會釋放能量，所以你所感覺到的熱就是來自那些釋放的能量。

Okay, so, why can't I just power my laptop with alternating current?

好的，那為什麼不能直接用交流電來充我的筆電呢？

If that's coming out of the wall?

畢竟從插座出來的就是交流電？

Yeah, that works just fine for things like lightbulbs or a hairdryer, but electronics are a little more complicated.

好，對於燈泡或是吹風機等等是可以的，但電子產品的構造比較複雜。

If you were to send that alternating current power directly to your laptop,

如果你想直接用交流電來替你的筆電充電，

you'd probably see a puff of blue smoke.

你可能會看到它開始冒煙。

Oh god, that sounds bad.

天啊，聽起來不太妙。

Okay, so, if DC power is so great, then why don't we just have it in our houses in the first place?  

好的，如果直流電那麼好，為什麼不直接用直流電來供電呢？

So this goes back to the late 1800s.

這就要回溯到 1800 年代後期，

There were two guys who represented the two different kinds of power.

那時有兩個人分別代表不同的電力。

There was Thomas Edison, he was all about DC power,

愛迪生主張直流電比較好，

and then there's Nikola Tesla, he was your AC guy.

特斯拉則認為交流電比較好。

They're totally duking it out.

他們為了這個爭執不休。

Every time a new building goes in, it's kind of this 'oh, what's gonna happen?

每當要蓋新建築時，大家都會好奇會發生什麼事？

Are they going to use AC or they're going to use DC?

他們要用交流電還是直流電？

And what happens eventually is that AC power is much better at traveling long distances.

最後證明了交流電在長途傳輸上比直流電好很多。

So ultimately, the entire power grid gets set up to spread AC power.

所以之後所有發電系統都是使用交流電來傳導。

But today we have all these devices.

但現今我們有那麼多電子產品。

We have smartphones, we have electric cars, we have tablets, we have computers,

像是智慧型手機、電力車、平板、電腦等等，

and all these things are hungry for this DC power.

這些都需要直流電。

Do you think we could ever switch back and maybe realize

你認為我們有辦法換回去

Edison's original dream of DC power in every home?

並實現當初愛迪生推廣直流電的理想嗎？

The US has one of the best, most reliable power grids in the world, so people aren't saying "let's knock out this entire grid."

美國擁有世界上最好、最可靠的發電系統，所以人們不會想要把它們砍掉重練。

You could just have one converter box in your house,

只要在家家戶戶都安裝一個轉換器，

and that way you're not converting AC to DC at the level of every single device.

這樣你就不需要替你的所有電子產品做交流電和直流電的轉換。

So, if we can reduce the number of conversions from AC power to DC power, even a little bit, we're going to save a lot of energy.

所以，如果我們能減少交流電和直流電轉換的次數，一點點也好，我們就能省下很多的能源。