Replies

1. 
   CaseyR_ | Sep 13, 2001 05:33am | #1

   *
   there is a web site on geothermal heat pumps at
   http://www.igshpa.okstate.edu/
   and they have a list of certified installers, including a couple in Santa Rosa and one in Calistoga.

   As far as efficiency, the primary advantage of geothermal, as I understand it, is that the ground temperature does not vary as widely as the air temperature so in most locations, it is more efficient to use the 50 deg ground temperature than the 30 degree air temperature for the heat pump source. It would work against you, however, if the ground temp was 60 degrees while the air temp was 65 degrees and you wanted your house to be at 72 degrees. thus for heating if you had cool ground temp but had long periods of slightly warmer air temps, then you would would lose with geothermal. For cooling, however, I would guess that you would generally come out ahead with buried tubing rather than using air (I have been in Sebastopol on at least a couple of summer days when cooling would have been nice, so I am guessing that you will actually use it if you have it...). How cost effective it would be is a different matter - given a fairly significant cost of burying the tubing or drilling a well, I would guess that with mild temperatures you would take a long time to pay back the difference between standard and geothermal heat pumps.

   Solar collectors would probably be more cost efficient for heating the swimming pool and possibly for pre-heating the hot water.

1. 
   Sally_Stanford | Sep 14, 2001 02:25pm | #2

   *Casey - The web site is very helpful. We're also looking into solar collectors. Thanks.

1. 
   Art_B. | Sep 14, 2001 08:00pm | #3

   *"We've heard that since our location enjoys a moderate climate.... Whoever you heard that from is misinformed. A heat pump (even air to air)in a moderate climate will beat every other form of heat (except if you have a free energy source like your own wood lot) in economy. The inserted file is based on a 4T Rheem air-air unit for a 5000 sqft house, a ground source will beat the air-air unit whenever the outside temp is below about 55 F.

1. 
   Art_B. | Sep 14, 2001 08:03pm | #4

   *Sorry, posted wrong attachment 1st time

1. 
   Sally_Stanford | Sep 15, 2001 08:23pm | #5

   *Art - that chart is really encouraging - thanks!

2. 
   ken_ballard | Sep 16, 2001 03:57am | #6

   *Plan to build about 150 mi south of you and the building department doesn't allow pipes in the floor other than drains (at least that is what I've been told). It sort of makes a little sense because the ground shakes occasionally. My plans are a lots of insulation, using a little gas, a little solar, having an alternate heat source and a elect. generator. Good Luck!

2. 
   Sally_Stanford | Sep 16, 2001 03:57am | #7

   *
   We will be building a new 3000 sq ft home near Sebastopol, California, on a large piece of land & are considering geothermal energy to provide heat (radiant) & possibly hot water & swimming pool heating. We will not need air conditioning & the house will not have ducts. We've heard that since our location enjoys a moderate climate with few extreme temperatures, a heat pump will not be nearly as efficient as if we were building in Maine or Iowa. Does anyone have experience using geothermal energy for heat in a moderate climate? Does anyone know of a good geothermal-heat pump contractor in the Northern California area of Santa Rosa or Sebastopol? Any comments or advice would be most appreciated. Many thanks.