Engineers at MIT and the National Renewable Energy Laboratory (NREL) have designed a heat engine with no moving parts. Their new demonstrations show that it converts heat to electricity with over 40 percent efficiency — a performance better than that of traditional steam turbines. The heat engine is a thermophotovoltaic (TPV) cell, similar to a solar panel’s photovoltaic cells, that passively capt
![A new heat engine with no moving parts is as efficient as a steam turbine](https://cdn-ak-scissors.b.st-hatena.com/image/square/e36a6781ca3d2fc75a984e83edeaec3b0efb5e93/height=288;version=1;width=512/https%3A%2F%2Fnews.mit.edu%2Fsites%2Fdefault%2Ffiles%2Fimages%2F202204%2FMIT-Thermal-Batteries-01-press.jpg)