Hello all,
     I installed a ground source heat pump in my home. Electricity at=20
that time was running about 9 cents per kilowatt hour. The regular AC or=20
air sourced AC, it did not have the ability to supply heat cost about=20
$80 per month during the summer. The ground source AC dropped this to=20
$50 per month. The natural gas heater which was a 80% unit was costing=20
$175 per month. The ground source heat dropped this to $80 per month. We=20
also super insulated the home at the same time but we doubled the size=20
of the home from 1000 square feet to 2000 square feet. I figure the=20
extra insulation was pretty much a wash because of the size increase of=20
the home.
     We also put in a separate electrical service that allowed the power=20
company to shut off the water heater and the heat pump during peak=20
periods. So the power for the water heater and heat pump was reduced to=20
7 cents per KW/hour. Our neighbors who were using oil heat had bills=20
that were running from $250 to $350 per month during the winter. We also=20
had two neighbors who were heating with wood. One of them was buying his=20
wood from another party and he was paying from $300-$550 per month.=20
Ouch!! The other was burning about one acre of timber per winter.
     I believe in ground source heat pumps but it is extremely important=20
that the cooling lines be properly installed in the ground. They need to=20
be imbedded in soil that has be thoroughly saturated with water. The=20
also need to be buried a minimum of 6 feet down. It is important that=20
they are not buried in sandy or rocky ground. The sand will not hold nor=20
conduct heat correctly. Rocky ground is even worst as the rocks will=20
wear holes into the tubes. If there are no rocks near the tubing it will=20
last almost forever. Another thing that is very important is that the=20
system is thoroughly purged of all air. If air is left in the system it=20
will cause cavitation problems. This will severely cut down on the=20
efficiency of the pumps. It will also severely shorten the life of the=20
circulation pumps.
Thanks,
rich!

On 6/29/2014 5:56 PM, Peter Johansson wrote:
> On Sun, Jun 29, 2014 at 10:15 AM, Justin Richards
>
>> Curiosity regarding ground heat pumps got the better of me and now after=
 a
>> little research have concluded that I should have built the house
>> underground rather than trying to exchange heat with the underground.
>

--=20
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