mhpr262
Member
There are a number of quite interesting concepts being developed right now that would work very well as range extenders similar to what is in the BMW i3 - the Achates Opposed Piston engine, or the Toyota Linear Free Piston engine. The fomer has demonstrated an efficiency of 43%. Considering the residual heat couldbe used for cabon and battery pack warming in cold weather it would be a valuable addition to larger EVs.