I read that rocket engine (or rocket itself) could practically acheive 70 percent of absolute efficiency.http://en.wikipedia.org/wiki/Rocket#Energy_efficiency
If I no make mistake a rocket produce very hot exhaust gases
which have practically the same temperature as fuel combustion.
Lets say we have the following example:
Rockets are flying on low altitude and doing some job,for example deliever freights.
On trajectory of their flights are installed Stirling engines (on towers) which capture
very hot exhaust of rockets and convert it into usefull work.If those Stirling engines
work close to ideal Carnot cycle their efficiency will be over 70% if hot sink temperature (rocket exhaust) will be 1300 K.
70%+70%=140% of total system efficiency.
Is there some mistake or nature`s law violation?