Green Dream: Putting the Earth to Work With a Geothermal Heating System

I do not understand this concept.The inground temperature is a constant 50 degrees so how can I heat to lets say 70 degrees.Where does the extra 20 degrees come from?Chuck

I would really like to know more info about this project. I would like to know if your 3500 sq ft included any attic or basement space? Also, can you provide the name of the company that you used? I have a house in NE Pennsylvania. The house is about 3600 sq ft without the attic and basement, although I would like to heat and cool those spaces too. I had one company come out to give an estimate for geothermal and I got a price of $80,000. I had figured myself that I would spend about $24,000.. My house, unfortunately, sits on a hill and has a long driveway.. The driveway we have coined the term 'the mansion walk', only because it seems every contractor that comes out, multiplies the price of jobs by the number of steps and the height of the house.. It's really just a simple house though. I cannot seem to find a good, reputable contractor to give an honest price for anything.

I would really love to use geothermal. The house currently has a very old and wasteful gas boiler that seems sized for a school, rather than a house. It's 400,000 btu. One of the heating contractors said the house only needs 179,000, though, I don't know if I can believe it.

"Spliceguy" The first thing that you need to do is factor your heat load- I have no idea how your house was built- what sort of windows, insulation you have- but once you get your values established by an engineer you will have a solid idea of what your true requirements are- Geothermal setups are based on Ton's your house could require a five ton system-just a guess- That would be three vert holes of about 375 ft each and your internal hardware- If you were paying someone and not doing any part of it as a DIY'er it could easily be $30,000- $36,000- if you did some work I could see you getting closer to $28,000. VERT and HORIZ come in at about the same cost when you factor everything in and your site with it's steep location sounds like VERT. Get your house loads established FIRST. Contact a good local HVAC company that does GEO work- They should be able to give you a number breakdown that shows the cost of drilling (Outside work) and the hardware (Inside work)-then it's all clear and you can compare APPLES to APPLES. Also understand that drilling rigs also work outside of GEO installers and you can hire them on your own to work for you- again markups exist in every business and the more time that you take to educate yourself and run the job the more you stand to save

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Popular Science Magazine

I too would like the name of the company you used to install your geothermal heating system.

I have a house with similar surface area, but have an existing 312 ft hole drilled for my on site water use. Could this hole also be used to supply some portion of my hot water and heating needs? Have you talked to any of these companies about such an approach to reducing the large start-up cost? This might be a good article to consider in the near future. There are a lot of people in my area that supply their own on site water needs.

We are currently in the midst of installing a Horizontal system which is only good if you have a very understanding wife (we have 5 acres of which a third now looks like scorched earth). Unfortunately the rebates in Ontario Canada are a bit smaller (approx $7000) bringing our final cost in around $23000.

Still, it will be great not to have to order furnace oil this winter.

I look forward to further progress updates.

Hi John

I'm planning a build in Argyle. Interested in your geoexchange choice. One long-term geoexchange guy in the area is a strong proponent of vertical standing water column. I'm wondering if you looked into that? I'm also interested in lateral - we have a long (read very long)drive and potentially buried electric trench to install. VSWC guy sez you need to get a horizontal system to 15' before you can be assured of no thermal losses - that's alot different than 6'! Any input would be great.

We installed the equivalent of a 5 ton loop (we only need 3-4 but the excavation is the expensive part so while we had the equipment I made sure the loops were over engineered). That resulted in approximately 3000ft of pipe and 1500ft of trench 6ft deep. I've heard of systems going to 8', but 15' seems extreme (and expensive).

Where can I get more info on these DIY efficient windows. We are building our own SIPs home right now and are nearing the cutouts for the windows phase. I would love to make my own windows and expected that article in this month's Popsci after it was mentioned in last month's geothermal article...I was disappointed to see that it was not in the magazine. Whats the story?

Thanks,
Matt

Oh, and on the geothermal topic: For a measly $677 we are installing SDR pipes to pump our air through for free cooling (and preheating makeup air in the winter). The pipes will be 6' below ground using the trenches that were already dug for pouring the footings. As a bonus, humidity in the house will be controlled by the rate at which the air is pumped through the SDR tubes (a simple speed control switch on our blowers). The house is small (20x24) and highly insulated with SIPs, so the 9400 BTU/hr system that these pipes provide should be plenty of free geothermal AC.