Toyota has developed a high-tech, two-cylinder, internal combustion engine to keep an electric car charged.
It’s effective because it never has to turn a crankshaft or any other shaft or gear just about. Its piston goes up and down merely to provide AC electricity to charge a battery.
The engine is two feet long and measures 8 inches round. Road and Track says it could generate 15 hp which would be enough to keep a compact electric vehicle rolling at highway speed even if the main drive battery gets depleted, according to Road and Track.
Toyota says its simple engine — which it calls the Free Piston Engine Linear Generator (FPEG) — achieves a remarkable thermal-efficiency rating of 42 percent in continuous use.
Below is a visualization:
