"nick smith" wrote in message
...
Soil heat recovery systems are even cheeper .............
400% efficient, for each 1 unit you put in, you get 4 out - wow !!
Maybe, but how much real estate do you need and what are the economics of
a system,
including instal costs to provide a 4 bedroomed detached house with heat
and hot water
year round when oil and gas are available at a cost of 1 or 2 p per kwH ?

I am not saying its bad, just wondering if its economically viable at the
moment in the UK

Unfortunately installation appears to start at about £8k and work upwards so
they never get to a payback situation for many users. Problem is you need a
double stage compressor system if you want hot water and radiators, whereas
the cheaper units sometimes quoted only supply underfloor and pre-heat to
the water tank before an immersion heater.

What I really don't understand is why all these units run on electrictity.
If they used oil or gas the running costs would be under half and they would
then be economically viable.