【英语时差8,16】太阳能(上)(在线收听

Did you know that enough sunlight falls on the earth’s surface every minute to provide energy for the entire world? The trick, though, is turning sunlight into power we can use for things like heating water and making electricity. And there are two types of technology used to do this: thermal solar devices, and photovoltaic, or PV, solar panels. So, what’s the difference? Thermal solar technology is the more straightforward of the two. To heat water for a home, for example, thermal solar typically involves panels that capture sunlight and use it to directly heat air or water. There are no wires, switches, or batteries. It’s a fairly direct and efficient conversion of sunlight into heat.
 
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