So, some really smart people at Cornell have created organic LEDs that can both emit light, and create energy from light. This makes a lot of sense - one doesn’t need nearly as many light-producing devices when it’s bright and sunny outside, but those lazy regular light bulbs just sit there during the day, mocking the environment. Even the fancy CFLs don’t do anything useful when they’re not turned on.
I’ve always thought we should do more of this - collect energy that’s already there when we don’t need it so we don’t have to buy as much from the power company when we do. Efficient appliances are great, but appliances that gather some or all of the energy they need to run are even better.