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Scientists Develop Solar Cell That Can Also Emit Light
An anonymous reader writes: "Scientists at the Nanyang Technological University have developed a solar cell that not only converts sunlight into electricity but also emits light as electricity passes through it. Tuning the composition of the solar cell enables it to emit different wavelengths of light (abstract), and because it is only about 1 micrometer thick, the material is semi-translucent and therefore could potentially be used in windows. The solar cell is comprised of the semiconducting mineral perovskite, which has been studied as a replacement for silicon in solar panels since 2009. Perovskite solar cells are not yet as efficient at energy conversion as silicon solar cells, but gains in this area of development coupled with cheaper manufacturing costs (10-20 cents per watt projected as opposed to 75 cents per watt with silicon solar panels and 50 cents per watt with fossil fuels) make perovskite a popular subject matter in the solar cell industry."
Absolutely brilliant comment. Also, you are correct.
For those who didn't get this post: A transducer is a transducer. It can go either direction, as the physical mechanism is the same, whether one direction or the other. For example, electromagnets move a speaker cone to create sound. Yell at a speaker, and the sound pressure will generate a small voltage (a microphone).
When poster called it a "one way street," he was referring to the way we engineer and design these transducers. They are optimized, for example to produce sound accurately. This inevitably leads to design trade-offs and optimizations for a particular application. That's all. No one is threatening the second law.
When land-line phones were wired (not cordless), I discovered as a child that I could yell into the earpiece, which modulated the voltage on the line, and a faint sound could be heard at the other end. The implications for eaves-droppers was that removing the microphone from your phone handset would not render you undetectable to the other people on the line, precisely for the reasons above.