Tim Lamb wrote:
In message , Roger Chapman
writes
The Natural Philosopher wrote:

Mr Sandman wrote:

It sounds like you can get useful heat from that size of lake, i
have just installed a GSHP on my place which is 170sqm of floor
space. Its a 2kw/12kw Heat Pump, but we use 600m of ground loop,
some of it in a well.

600m seems a lot. Is that the normal sort of length for a ground
loop and (without the well) how much land would be needed?
a lot depends on the soil. dry sandy is crap, wet soggy clay is very
good. I was quoted 200-400m in clay, no loop within 2 meters of any
other, for 12kw peak.
so 400 square meters minimum, for me, 800 squares better.

0.1 to 0.2 of an acre seems to give me a better idea of the size.
Should fit in some (but by no means all) back gardens but installation
would make a complete mess of said garden even if it is practicable to
dig the trenches at 2 metre centres. If I ever get round to it I might
consider the adjacent field instead but that could bring its own
problems.

If I ever get round to GSHP using buried pipe I will try to *mole* it in
rather than trench. Subsoils here are clays and gravel and I have pulled
50m lengths of blue poly for water supplies without problems. I like the
manifold idea as pulling loops with more than two legs would be
difficult. Luckily the *moles* will fill with water so there is no lack
of contact.


you hope. here they use moles to drain fields ;-)

regards