Materials engineered to give off precisely tuned wavelengths of light when heated are key to new high-efficiency generating system.
MIT has developed a new photovoltaic energy-conversion system that can be powered solely by heat, generating electricity with no sunlight at all.
These whiz kids have engineered the surface of a material to convert heat into precise wavelengths of light. These wavelengths are chosen to match those of photovoltaic cells that can best become electricity. The new discovery combines burning butane and nanometer-sized pits to fine-tune those wavelengths. Then they’re paired with PV cells that are tuned into those wavelengths to suck out the energy.
Why should we care? The end-product of all this is a generator the size of a dime that can run three times longer than a lithium-ion battery—something those MIT students must really hate. That generator can be recharged immediately by inserting a tiny cartridge of fresh juice. Oh, and they also made a radioisotope that produces heat from radioactive decay. It could quite possibly power its own electricity for 30 years. NBD.
So the former could be used to power, say, a mobile device, and the latter could be used to power say, an entire spacecraft on a long mission. Either way, those blessed MIT geeks have taken one small step for battery power, and one giant leap for all those people out there who can’t remember to charge their gadgets.
Photo credit: Justin Knight