In a not-too-far-off future, in addition to solar panels, houses may integrate energy-producing rain panels on their roofs. Chinese researchers have developed a device that produces energy by collecting raindrops. We’re all familiar with photovoltaic panels, which are very popular with homeowners, particularly in sunny locations. But how do you optimize your electricity production when you live in a country where raindrops are more likely to hit the pane than rays of sunlight? This is the puzzle that a team of Chinese scientists have been working on, by developing panels that work with raindrops. The principle is the same as...