"Ian Stirling" wrote in message
...
Pete C wrote:
On Tue, 27 Apr 2004 23:13:00 GMT, Ian Stirling
wrote:

Soil heat recovery systems are even cheeper .............
400% efficient, for each 1 unit you put in, you get 4 out - wow !!

But, electricity isn't much less than 4 times the price of gas.
Slightly less wow.

Hi,

If you don't have mains gas and could get 600% efficiency and aircon
too it starts to look a lot more convincing, plus there's no need for
oil or LPG delivery and storage.


Even if electicity generation is only 50% efficient it will create 3x
less CO2 than conventional heating, so it's pretty good from a green
perspective.

Of course, if you could get small 24*7 generators, doing the CHP
thing and putting the exhaust heat into the house, and the low-grade
residum into the heat source, plus using the shaft power to run a
compressor, then that would pretty much beat anything.

And the payback period would be a lifetime. Better spend the money on high
insulation, air-tightness and passive solar, etc.