by sparx »
Tue Apr 01, 2008 11:01 pm
Hi Helen,
Heat pumps do work be they air to water as used for swimming pools ect, or more expensive but more certain ground source types.
I have installed many air to water systems but you have to remember they give off large amounts of cold air, fine if you want to cool a beer by the pool but not good if pointing at the patio!
Many school & public buildings now use G-S heat pumps, 2 basic methods of extracting latent heat from ground, one drilling deep hole for pipes if ground space at a premium such as a built-up area, the other lays network of pipes at shallow depth under lawns ect. or in a pond.
Allegedly the return is around 3-4kW out for each 1kW of energy you put in to pumping system.
Certainly more reliable than solar panels, which are sold with the outright lie that 'they don't need sunshine, only daylight', mine don't give more than a pittance from November till April & they are expensive 'evacuated-tube' not cheaper 'flat plate' type, also need masses to do more than heat water.
One other thought is what about electric central heating boilers such as 'Amptec' sold now by Heatrae-Sadia, very efficient, small, controllable but electricity costs are over inflated so 98% efficiency of a lot of money is still a lot of money!
Have you looked at web site for Eden project, there was a fair comparison on there some time ago for various methods,
good 'converting', SPARX