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New Construction

smartcrow
17 years ago

My wife and I will be building a new home in the near future. As with most people who want to build a home, the list of "necessities" and the list of realities often vary. What I would like feed back on is what people think of our plan based on their previous experiences and areas of expertise.

We would like to design this house using insulated concrete forms. This seems to be an efficient building method that results in a strong, tight structure that is efficient in retaining heat. The house will be designed around an attached greenhouse and have a passive solar flavor. If possible we would like to use a direct exchange geothermal system with radiant floor heating (including the greenhouse) with either a wood stove or a masonry heater for supplemental heating. We would like to power this house with PV solar panels. With construction expected to start within two years, we hope to have enough time to achieve something close to our dream of being as close to off the grid as possible. The house will be located in Bucks Co. PA. Am I dreaming or can all these things be worked into a realistic design?

Comments (6)

  • smartcrow
    Original Author
    17 years ago

    Thanks Gary,

    I was begining to think my question wasn't going to be looked at by any one. With regard to the Geothermal heat pumps, I was hoping to power the compressor using electric from the PV system, there by eliminating any greenhouse gas. I was having a little trouble determining the electric requirements of the heat pump and other components of the system. Would they require more than my 3000 kw pv system could supply?

    I plan on using all of your above suggestions regarding the envelope, especially the windows! I will look at the links that you supplied in your reply thanks a bunch!

    Steve

  • fsq4cw
    17 years ago

    I too agree, sounds like youÂre on the right track.

    The inclusion of a DX geothermal unit is an important feature that I personally would NOT leave out. Should your new home require serious heating, domestic hot water, radiant in-floor heating and air-conditioning  NOTHING  can beat a DX triple function geothermal unit! This would be the simplest and smallest self-contained mechanical unit with everything indoors (except the buried ground loops).

    In terms of HVAC and hot water, thatÂs what I would install first; funds permitting, masonry heater next. If it ever gets blistering hot and humid, youÂre going to want that A/C!

    I guess I too have a bias. I would sacrifice the PV panels and any other solar plumbing, if I had too, but geoÂs at the top of the list!

    If your PV system IS "3000kw", you can run ANY residential system and still have your utility meter still spinning backwards like the prop of a P-51!

    SR

    Here is a link that might be useful: Nordic DX Series GSHP

  • smartcrow
    Original Author
    17 years ago

    Thanks,

    To all who replied! I think the plumber that I'm looking at doesn't do the DX. He has been in the business for 20 yrs and says he isn't comfortable putting copper in the ground. I kinda thought that was odd because most water lines from town water supplies are copper and rarely do you ever have a problem with them. Is there that much a benefit using DX over plastic tubing?

  • fsq4cw
    16 years ago

    Any method of geothermal will provide a satisfactory result  properly installed! The advantage of DX is less cost for drilling (about 40% shallower boreholes) and no circulating pump. DX also requires less real estate, if square footage is an issue.

    IÂd also rethink having a plumber install your geothermal, unless he is an IGSHPA accredited installer.

    SR

    Here is a link that might be useful: International Ground Source Heat Pump Association (IGSHPA)

  • DavidR
    16 years ago

    Heh. If you're planning a 3000 kW PV system, you must have one heck of a big roof.

    Let's see, 3000 kW = 3,000,000 watts (3 megawatts). 3,000,000 / 180 watts per (large) panel = 16,667 panels. Of course those 180 watt panels won't produce anything like 180 watts most of the time, but that's the (unrealistic) way most systems are rated anyway, so we'll let it go.

    Each panel is ~14 ft^2, so you'll need 236,810 square feet of roof space. That's 5.4 acres. It should work if your house is square and 487 feet on each side. Maybe a bit less, depending on roof pitch.

    Now, just for the fun of it, let's see how wealthy you are. In a quick look around the web I find that you can buy a pallet of 28 Sharp 180W PV panels for $24,640.

    You'll need 595 1/4 pallets. I bet they'll just throw in those last 7 panels free if you buy 595 full pallets. Your cost for 595 pallets of 180W panels (before quantity discounts) - just $14,678,650. Such a deal!

    Sorry, I couldn't resist. ;-)

  • smartcrow
    Original Author
    16 years ago

    No wonder it's taking so long for this solar thing to catch on!!! LOL

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