In message , The Natural
Philosopher writes

Oh, you're miles off there. Power stations are typically between
30-40% efficient. Even an old central heating boiler is twice as
good as that, and a modern one even more so.

No they are not.

They use 'condensing' technology as well, you know.

Supercritical can be over 60%...almost no one builds less than 45% today.

Thermal efficiency is a function of combustion temperature and
exhaust temperature. I doubt that any domestic boiler has a
combustion temperature as high as a power station, or an efflux
temperature as low (30C)
Umm... ISTR the steam cycle has a limit of 44% (Thermodynamics more
years ago than I care to remember). Obviously gas turbines do not
operate this way.


No. It purely dependent on how hot the steam is at the start, and how
cool at the end.

steam of 500C plus at the start and 30C or less at the end nets you
over 60%...

I'm not looking for a fight:-)

My recollection is that the limit is caused by the latent heat locked in
at vaporisation. If you can usefully extract this from your cooling
tower then overall thermal efficiency goes up.

They were looking at Magneto Thermo Dynamics as a way of *topping* when
I were a lad.

regards

--
Tim Lamb