Energy from a pit in the garden?????!

[reddyreddy]

I had an EPC done on my hosue yesterday in preparation for selling and the guy who came and did it was quite full on about energy savings. He mentioned solar panels etc but also talked about some sort of system whereby you dig out your garden, lay pipes of some description then fill in, the soil warms the pipes and provides free energy for life. Not the sort of things you could do to an existing house or garden as the excavation needed would be on a massive scale but we are considering a part finished house with just bare land as the garden, could be an ideal time to do it. Anyone know what it's called?!

[InfraDig]

I think it is a ground source heat pump.

[Psi (Pronounced 'Si'!)]

yes ground source heat pump

http://en.wikipedia.org/wiki/Geothermal_heat_pump

very clever.  They do a smaller horizontal hole for domestic applications these days.

[reddyreddy]

Fab! Thank you!

[PurpleHeather]

Geothermal heat is what they call it.

It seems that there is a constant warm temperature at a certain depth which is apparently why coal miners in the middle of winter on the surface could strip down when working in the pits and still be sweating.

People live in caves in some very hot places even today because of the temperature is constant 24/7.

It seems that there is no reason at all why we should not get our heat from the  earth. Other than the initial cost and the fact that 'they' want to sell us fuel.

There is a restaurnt in Lanzerote where you can buy your steaks cooked on a griddle set up over a volcano. It is well worth a visit to that National Park which is something else to experience. Wear thick soled shoes if you go though, the land is very hot to stand on. They pour down a little water and it shoots back up as pure steam. That energy could also be used to generate electricity I feel sure.

[Chrispy]

Geothermal heat is what they call it.

No, Geothermal is when there is a heat source underground, you send liquid down and it comes up hot.

Ground source heat pump is where you pump the heat out of the liguid, bit like a fridge/freezer works, you then send the extra cold liquid into the ground, where it is warmed up by the not so cold ground.

The pump uses quite a bit of electric to run, so it is not free energy, but is very efficient.

[PurpleHeather]

This site on Geothermal heat may interest some.

http://images.google.com/images?oe=UTF-8&sourceid=navclient&gfns=1&q=geothermal+heat&um=1&ie=UTF-8&ei=sbCaS5ClGJCRjAe5nPWkDA&sa=X&oi=image_result_group&ct=title&resnum=4&ved=0CCwQsAQwAw

[Psi (Pronounced 'Si'!)]

ground source heat pumps are sort of based on the idea that 1 metre of so it is a constant 12 degrees.  Saving being that in winter you are heating from 12 degrees up  (as opposed to heating from say 0 degrees). that being the logic to heat to 19 degrees you are heating 7 degrees rather that 19.  Make sense?  12 degrees in summer is seriously cold also!

[Unwashed]

ground source heat pumps are sort of based on the idea that 1 metre of so it is a constant 12 degrees.  Saving being that in winter you are heating from 12 degrees up  (as opposed to heating from say 0 degrees). that being the logic to heat to 19 degrees you are heating 7 degrees rather that 19.  Make sense?  12 degrees in summer is seriously cold also!

No, that's not it, it's like Chrispy says.  It doesn't really matter how cold the ground is, the point is that it still contains heat energy, and by using a little bit of energy to drive a pump you can pump that energy out, just like the heat gets pumped from the inside of a fridge.