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Module 1-2 Ⅰ.阅读理解 (2015·内蒙古包头一中三模) Electric cars are dirty. In fact, not only are they dirty, they might even be more dirty than their gasolinepowered cousins. People in California love to talk about “zeroemissions (排放) vehicles”， but people in California seem to be_clueless about where electricity comes from. Power plants mostly use fire to make it. Aside from the few folks who have their roofs covered with solar ceils, we get our electricity from generators (发电机). Generators are fueled by something—usually coal, oil, and also by heat generated in nuclear power plants. There are a few wind farms and geothermal (地热的) plants as well, but by far we get electricity mainly by burning something. In other words, those “zeroemissions” cars are likely coalburning cars. It's just because the coal is burned somewhere else, so it looks clean. It is not. It's as if the California greens are covering their eyes—“If I can't see it, it's not happening.” Gasoline is an unbelievably efficient way to power a vehicle; a gallon of gas has a lot of energy in it. But when you take that gas [or another fuel] and first use it to make electricity, you waste a nice part of that energy, mostly in the form of wasted heat—at the generator, through the transmission lines, etc. A gallon of gas may propel your car 25 miles. But the electricity you get from that gallon of gas won't get you nearly as far—so electric cars burn more fuel than gaspowered ones. If our electricity came mostly from geothermal, or hydro, or solar, or wind, then an electric car truly would be clean. But for political, technical, and economic reasons, we don't use much of those energy sources. | 
