Naked Science Forum

Non Life Sciences => Technology => Topic started by: thedoc on 29/07/2015 23:50:01

Title: Why not use a sterling engine to recover some of the wasted energy from the combustion engine?
Post by: thedoc on 29/07/2015 23:50:01

C Bruce Rodgers asked the Naked Scientists:
   
Why not use a sterling engine to recover some of the wasted energy from the combustion engine?  
Poor weight/power ratio?


What do you think?

Title: Re: Why not use a sterling engine to recover some of the wasted energy from the combustion engine?
Post by: evan_au on 30/07/2015 12:44:35

The efficiency of a heat engine is better when there is a larger temperature difference between a heat source and a cold sink.

If you want good efficiency from the Sterling engine, you will maximise the temperature between its heat source and the cold sink. Unfortunately, this reduces the temperature difference of the main engine, and it loses efficiency.

The most efficient power generators are those located near residential or industrial users of low-grade heat. They appreciate a source of warmth, without trying to drive a heat engine with it.