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It’s not hard to understand why a big utility might not like the idea of homes, businesses, schools, and even government buildings being covered in solar panels. If every building in America is generating its own solar energy, that throws a big wrench(猛拉) into their business model. It’s why utilities have historically been opposed to solar power, say solar’s advocates. But as most states have passed renewable-energy standards recently, mandating(命令, 指示) that a certain percentage of their energy come from renewable sources, utilities have become reluctant players in the solar game because, frankly, they have no choice. Rather than get on board with rooftop solar, though, utilities decided to do what they do best: build a centralized system of large power plants, and make money by charging customers for taking power off the grid. While large-scale utility projects do hold the promise of generating massive amounts of electricity, so far they’ve delivered precious, few new sources of electricity, as dozens of proposed projects are languishing in the application process.
Renewable-energy standards in many states require that