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  • So, I have this problem. When I plug my laptop charger into an outlet, that weird box between the plug and the part where it connects to my computer, it gets super hot, like I can't even touch it.

  • So, I've invited Audrey Quinn from NPR's

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

  • So, Audrey, what's the deal? QUINN: "The first thing you have to understand is

  • that the kind of power that comes out of your wall is actually different from the kind of power that your electronics want.

  • It comes out in the form of alternating current electricity.

  • That means the electrons are pulsing back and forth

  • And your electronics want what's called direct current power, that's where the electrons

  • are flowing straight like a river. So, they have to convert it. And when they

  • do that conversion energy is wasted, so what you're feeling is energy lost in the

  • form of heat." Okay, so, why can't I just power my laptop with alternating current?

  • If that's coming out of the wall? QUINN: "Yeah, that works just fine for things like

  • lightbulbs or a hairdryer, but electronics are a little more complicated.----

  • If you were to send that alternating current power directly to your laptop, you'd probably

  • see a puff of blue smoke." Oh god, that sounds bad.

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

  • place?   This goes back to the late 1800s. There were

  • two guys who represented the two different kinds of power.

  • There was Thomas Edison, he was all about DC power, and then there's Nikola Tesla,

  • he's your AC guy. They're totally duking it out. Every time

  • a new building goes in, it's kind of this 'oh, what's going to happen? Are they

  • going to use AC or DC?' What happens eventually is that AC power is

  • much better at traveling long distances. So, ultimately, the entire power grid gets

  • set up to spread AC power." But today we have all of these devices.

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

  • and all these things are hungry for DC power. Do you think we could ever switch back

  • and maybe realize Edison's original dream

  • of DC power in every home? QUINN: "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.'

  • You could just have one converter box in your house, and that way you're not converting

  • AC to DC at the level of every single device." 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.

So, I have this problem. When I plug my laptop charger into an outlet, that weird box between the plug and the part where it connects to my computer, it gets super hot, like I can't even touch it.

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B1 US Vox power dc quinn laptop charger

Why your laptop charger is so hot

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    Ray Du posted on 2016/02/24
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