Advertise on Bikeforums.net



User Tag List

Page 1 of 2 12 LastLast
Results 1 to 25 of 34
  1. #1
    la vache fantôme phantomcow2's Avatar
    Join Date
    Aug 2004
    Location
    NH
    Posts
    6,266
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)

    Geothermal heating/cooling

    Anybody here running a geothermal closed or open loop heat pump?

    If so, what was your total cost? Including supplies, digging, installation, and miscellaneous expenses.

    My parents have been looking into either solar heating or geothermal heating/cooling for our home. It would be a retrofit, and will certainly be very costly. Regardless, I've run the #'s with a variety of payoff periods and they are all quite short (relatively speaking). By the time my parents are ready for retirement, any system will have been paid off, convenient. We have a contractor coming tomorrow to give us a quote. I'm curious to know what other's have experienced though.
    My gut feeling is 20,000 dollars.
    C://dos
    C://dos.run
    run.dos.run

  2. #2
    austropithicus
    Guest
    Quote Originally Posted by phantomcow2 View Post
    My gut feeling is 20,000 dollars.
    Yep, $20,000 is about right.

  3. #3
    Senior Member randya's Avatar
    Join Date
    Jul 2003
    Location
    in bed with your mom
    My Bikes
    who cares?
    Posts
    13,696
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    solar is getting cheaper, but right now production is lagging behind demand; if you wait a bit, new technology and more production is coming on line within the next year or so. heat loops might be going up because drilling is energy intensive and steel, etc. is getting more expensive. closed loop is more environmentally friendly but you need a larger contact area for the heat exchanger, open loop you need a good aquifer and maybe a state permit of some type (UIC or some form thereof).

  4. #4
    la vache fantôme phantomcow2's Avatar
    Join Date
    Aug 2004
    Location
    NH
    Posts
    6,266
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Well, we're not looking at solar panels for electrical generation. These are evacuated tubes. Do a google search, they're fantastic. I believe they're over 70% efficient as well.
    $100 a tube, one tube will generate 1875BTU assuming 4.5hours of sunlight.

    I would prefer closed loop because it does seem more environmentally friendly. Also, by principle, it seems to be more sustainable. Given that a geothermal system will reduce our annual costs by a good 70%, extra costs are quickly recuperated.
    C://dos
    C://dos.run
    run.dos.run

  5. #5
    Senior Member randya's Avatar
    Join Date
    Jul 2003
    Location
    in bed with your mom
    My Bikes
    who cares?
    Posts
    13,696
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    looks like evacuted tubes are for heating water not electricity gen

  6. #6
    just for randya gaston_45's Avatar
    Join Date
    Dec 2006
    Location
    Oregon
    My Bikes
    Gary Fisher Mullet
    Posts
    5
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by phantomcow2 View Post
    Geothermal heating/cooling
    That's the title of the thread Randya. He's asking about heating, not electrical generation.

    The only disadvantages with geothermal or solar heating are the added maintenance costs and it makes it harder to sell the house. If your parents are going to live there the rest of their lives that won't matter though.

  7. #7
    Science Fanboy KrisPistofferson's Avatar
    Join Date
    Oct 2004
    Location
    POS Tennessee
    My Bikes
    Gary Fisher Simple City 8, Litespeed Obed
    Posts
    7,596
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Randya sure has his share of stalkers as of late.

  8. #8
    just for randya gaston_45's Avatar
    Join Date
    Dec 2006
    Location
    Oregon
    My Bikes
    Gary Fisher Mullet
    Posts
    5
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Nah, I'm not stalking him. I really don't care about him at all, he just happened to make two posts that completely ignored the title of the thread. The second one after the OP specifically corrected him about not wanting to generate electricity.

    If you're talking about the "just for randya" under my name it came from this thread:
    http://www.bikeforums.net/showthread...=296408&page=2

    Which reminds me, how are them chops randya?

  9. #9
    Senior Member randya's Avatar
    Join Date
    Jul 2003
    Location
    in bed with your mom
    My Bikes
    who cares?
    Posts
    13,696
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by gaston_45 View Post
    ...It makes it harder to sell the house.
    how do you figure that? A hot tub is a maintenance nightmare, and might make it harder to sell, but who would object to lower utility bills? I also don't see how a heat pump or solar heater is any more maintenance than conventional HVAC or hot water heater systems.

  10. #10
    just for randya gaston_45's Avatar
    Join Date
    Dec 2006
    Location
    Oregon
    My Bikes
    Gary Fisher Mullet
    Posts
    5
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    A solar water heating system uses pipes and collectors to heat water. Those collectors sit on the roof of your house and the pipes are run inside your house. If they aren't properly maintained then they leak and destroy your house. At the other end you have to have heat exchangers either added to the existing furnace or one that sits in parallel with a backup furnace for when there isn't enough solar heat. Double maintenance again. And unless you live in Arizona or other desert areas in the southern U.S. you won't gain a whole lot with solar so it takes forever to gain back all the initial costs plus ongoing extra maintenance costs.

    This makes it hard to sell houses because people don't want to do extra maintenance and certainly don't want their house flooded when the drain valve doesn't activate and the pipes freeze. Unless someone is really into alternate heating methods they really don't want to deal with the extra hassle so they pass on homes with it.

    The geothermal heat pump is good, if you have a big enough area or the ground is of the correct type to sink the well vertically but again, pipes running into the ground require some extra maintenance.

  11. #11
    My tank takes chocolate. FlowerBlossom's Avatar
    Join Date
    Jun 2005
    Location
    Olympia, WA
    My Bikes
    Trek 600 series touring bike, Trek 800 hybrid, Bianchi
    Posts
    6,344
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by gaston_45 View Post
    A solar water heating system uses pipes and collectors to heat water. Those collectors sit on the roof of your house and the pipes are run inside your house. If they aren't properly maintained then they leak and destroy your house. At the other end you have to have heat exchangers either added to the existing furnace or one that sits in parallel with a backup furnace for when there isn't enough solar heat. Double maintenance again. And unless you live in Arizona or other desert areas in the southern U.S. you won't gain a whole lot with solar so it takes forever to gain back all the initial costs plus ongoing extra maintenance costs.

    This makes it hard to sell houses because people don't want to do extra maintenance and certainly don't want their house flooded when the drain valve doesn't activate and the pipes freeze. Unless someone is really into alternate heating methods they really don't want to deal with the extra hassle so they pass on homes with it.

    The geothermal heat pump is good, if you have a big enough area or the ground is of the correct type to sink the well vertically but again, pipes running into the ground require some extra maintenance.
    The logic in this is not very good....indoor plumbing seemed to have increased the value of houses plenty. In fact it's kinda hard to buy or sell a house w/o it (unless it's a very rural location). No one pays less for a house w/ an extra bathroom, even when you know they've hidden the dry rot or mold or leaky pipes somehow. Solar systems are just an extra bathroom, but actually save energy--thus have better returns. Extra bathrooms are just black holes that suck up your money. I'd take a solar-heated house over an extra bathroom any day. Ignorance is what would keep the prices down, not reality.

    Second, your backup heater could be just the furnace, not connected to the water system. Or, electric baseboard heaters---heating room by room--again, not connecting the water.
    Feminism is the profound notion that women are human beings.

  12. #12
    Dude wheres my guads? skinnyone's Avatar
    Join Date
    May 2005
    Location
    Guess
    My Bikes
    Not enough
    Posts
    2,680
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Pcow are your parents in NH too? I would guess that Geothermal would be more feasible in a seismically active area than over here? It would all depend on how thick the mantle is in their neck of the woods I guess.

  13. #13
    Videre non videri
    Join Date
    Sep 2004
    Location
    Gothenburg, Sweden
    My Bikes
    1 road bike (simple, light), 1 TT bike (could be more aero, could be lighter), 1 all-weather commuter and winter bike, 1 Monark 828E ergometer indoor bike
    Posts
    3,202
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    My parents installed geothermal heating a few years back. 2003 or 2004. Before that, the house was heated by electricity directly. Their annual electricity usage went from 29 500 kWh to 12 000 kWh. Around 7000 of that is the electricity used for things other than heating (lights, washing machine, dishwasher, fridge, freezer, electronics, et c), so effectively, the electricity used for heating is now only about a quarter of what it used to be!

  14. #14
    Videre non videri
    Join Date
    Sep 2004
    Location
    Gothenburg, Sweden
    My Bikes
    1 road bike (simple, light), 1 TT bike (could be more aero, could be lighter), 1 all-weather commuter and winter bike, 1 Monark 828E ergometer indoor bike
    Posts
    3,202
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by skinnyone View Post
    Pcow are your parents in NH too? I would guess that Geothermal would be more feasible in a seismically active area than over here? It would all depend on how thick the mantle is in their neck of the woods I guess.
    That has little to do with it. The geothermal gradient is what's relevant.

    My parents live in a very stable area, that hasn't seen any tectonic activity since the late Permian, and barely even then. Their hole is 130 m (~430 ft) deep.

  15. #15
    la vache fantôme phantomcow2's Avatar
    Join Date
    Aug 2004
    Location
    NH
    Posts
    6,266
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Okay,
    It is less maintenance for a geothermal system than anything else. Spoken from the contractor himself, maintenance involves...

    Replacing air filter annually, IF you have a central air duct system.
    Periodical cleaning of water filter (for open loop).

    That's it. Geothermal systems make the value of the home increase. There is no maintenance with the underground pipes. They have a life span of about 200 years, they are plastic so no corrosion. You should never have to touch them again.

    A solar heating situation is again essentially zero maintenance. For one, it's an antifreeze solution that circulates in the pipes. That's just extra plumbing. Yes, there is a possibility of maintenance, but no more maintenance than you do for your existing household plumbing...
    C://dos
    C://dos.run
    run.dos.run

  16. #16
    la vache fantôme phantomcow2's Avatar
    Join Date
    Aug 2004
    Location
    NH
    Posts
    6,266
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Anc CDCF is right. You're not looking to dig down to reach the super heated core of the earth...
    You're looking for for a consistent temperature, which can be found by digging about 10ft underground.
    C://dos
    C://dos.run
    run.dos.run

  17. #17
    Dude wheres my guads? skinnyone's Avatar
    Join Date
    May 2005
    Location
    Guess
    My Bikes
    Not enough
    Posts
    2,680
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by CdCf View Post
    That has little to do with it. The geothermal gradient is what's relevant.

    My parents live in a very stable area, that hasn't seen any tectonic activity since the late Permian, and barely even then. Their hole is 130 m (~430 ft) deep.

    Yeah, that was an erroneous suggestion. I put together a thin/fractured tectonic plate with higher seismic activity which is not necessarily true. I guess in Sweden and a lot of places in the Alps where you find natural hot springs and such, you would'nt have to go too deep. Places like Yellowstone too I figure. Not sure about NH.

    Is there a map that shows geothermal gradients for different parts of the world or is it a drill and find out operation?

  18. #18
    Senior Member randya's Avatar
    Join Date
    Jul 2003
    Location
    in bed with your mom
    My Bikes
    who cares?
    Posts
    13,696
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    the geothermal gradient is different than being near active hot springs. Of course if you live in Iceland, Klamath Falls or Yellowstone, you're luckier than everyone else.

    The average geothermal gradient of the earth is about 25°C/km. However, in volcanically active areas like island arcs, the temperature may increase by about 30-50°C/km. In areas such as ocean trenches, the temperature may increase by as little as 5-10°C. The following diagram illustrates how the earth's geothermal gradient varies with tectonic setting. The dashed yellow line represents the 500°C isotherm.



    High Geothermal Gradient: Mid Ocean Ridges, Arc Orogens, Spreading Ridges. Temperature increases quickly with depth, due to rising hot magma beneath.

    Low Geothermal Gradient: Subduction Zone. Temperature increases slowly with depth, ie: cool rocks are found deeper in the earth. This is due to the relatively cool sediments and fluids (ie: seawater) being subducted. [At great depth the rocks start to metamorphose and eventually melt, forming magma. The temperature gradient is then deflected back upwards due to the rising hot magma.]

    Average Geothermal Gradient: Continent. Continental areas away from tectonically active zones have average geothermal gradients

    http://www.eos.ubc.ca/courses/eosc22.../gradient.html
    http://www.enotes.com/earth-science/geothermal-gradient
    http://en.wikipedia.org/wiki/Geothermal_gradient
    Last edited by randya; 01-03-08 at 03:24 PM.

  19. #19
    Dude wheres my guads? skinnyone's Avatar
    Join Date
    May 2005
    Location
    Guess
    My Bikes
    Not enough
    Posts
    2,680
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by randya View Post
    the geothermal gradient is different than being near active hot springs. google is your friend.

    http://en.wikipedia.org/wiki/Geothermal_gradient
    huh? someplace near a hot spring will have a shallower gradient right? Which means given a target temperature, you would dig lesser near a hot spring than elsewhere.

  20. #20
    Senior Member randya's Avatar
    Join Date
    Jul 2003
    Location
    in bed with your mom
    My Bikes
    who cares?
    Posts
    13,696
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    higher gradient near hot springs~faster increase in temp with depth.

    All you really need to do with most heat pumps is get your loop below the frost zone, that way they heat in the winter and cool in the summer. Then you need enough contact area for the desired heat exchange to take place.

  21. #21
    Dude wheres my guads? skinnyone's Avatar
    Join Date
    May 2005
    Location
    Guess
    My Bikes
    Not enough
    Posts
    2,680
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by randya View Post
    higher gradient near hot springs~faster increase in temp with depth.
    Wait .. .

    "rate of increase in temperature per unit depth=gradient".. The delta between a hot spring to the core is lesser than a corresponding non-hot spring area (Assuming same elevation). Thus the slope would be shallower for the hot spring. dtdegc/dx.

    All you really need to do with some heat pumps is get your loop below the frost zone, that way they heat in the winter and cool in the summer.
    That I agree, how deep do we gotta go is what I am curious about. The deeper the hole, more the maintenance and fixed costs.

  22. #22
    Senior Member randya's Avatar
    Join Date
    Jul 2003
    Location
    in bed with your mom
    My Bikes
    who cares?
    Posts
    13,696
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    you're not measuring the gradient up from the earth's core, silly. You are measuring it down from the earth's surface temperature.

  23. #23
    Videre non videri
    Join Date
    Sep 2004
    Location
    Gothenburg, Sweden
    My Bikes
    1 road bike (simple, light), 1 TT bike (could be more aero, could be lighter), 1 all-weather commuter and winter bike, 1 Monark 828E ergometer indoor bike
    Posts
    3,202
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    For my parents, about half of the total cost went into plumbing and new radiators, since they had no water-borne heating from before (all electric). Others around here often have oil burners with water circulation, and that makes the transition to geothermal much cheaper.

  24. #24
    la vache fantôme phantomcow2's Avatar
    Join Date
    Aug 2004
    Location
    NH
    Posts
    6,266
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    How can a deeper hole possibly mean more maintenance?
    Anybody here maintain their well holes?! There is no maintenance regarding a hole in the ground...

    We currently utilize hot water baseboard heaters with an oil burner + circulation pump. It does make hte transition a lot easier. We may have to replace the baseboard heaters though. The ones on here now are designed for 180 degree water, we need some that are more efficient in their heat dispersion, because the water from the heat pump will be 140 degrees at most.
    C://dos
    C://dos.run
    run.dos.run

  25. #25
    Senior Member randya's Avatar
    Join Date
    Jul 2003
    Location
    in bed with your mom
    My Bikes
    who cares?
    Posts
    13,696
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    believe me, you might need to maintain your well hole, esp. with an open system. for starters if the chemistry is right you could get mineral precipitates or iron reducing bacteria that clog the well and reduce the flow rates.

Page 1 of 2 12 LastLast

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •