terra, not terror

sharing ideas about a simpler way to live

Geothermal = Free Heat and A/C September 25, 2007

Filed under: alternative, energy — terra @ 7:57 am

Geothermal wells have the ability to provide heat and a/c naturally. One school in Massachusetts is tapping into geothermal, and they expect to save $17,000 a year. After 6 years, the investment will have paid for itself, and begin saving thousands from then on.

The geothermal system involves a series of three wells drilled 6 inches wide and 1,500 feet deep. At this depth, the earth’s energy warms the well water to a constant temperature of 50 to 60 degrees. The heated water is pumped out of the wells and into a heat exchanger. In the winter, the heat exchanger takes the heat out of the water, pressurizes the heat to raise its temperature even more, and uses it to warm the cold air in the building. In the summer, the heat exchanger absorbs the excess heat from the air, blows the newly cooled air back into the building, and discharges the unwanted heat back into the earth.

Massachusetts has other churches and schools opting for geothermal heat when it comes time to retrofit and replace old heating systems. Researchers at MIT have found that geothermal systems are more efficient, reliable, and cost-effective than wind and solar energy. This video should explain it all.

West Chester University in PA is also using geothermal energy, with plans to expand the program. Their Sustainability page has a nice, simple explanation of the process.

It just makes sense to make the extra investment now for long-term savings, and environmental benefits in the future. Other countries are using geothermal energy with great success. I hope to see more research into this potential.


7 Responses to “Geothermal = Free Heat and A/C”

  1. Brian Says:

    I *really* want to exploit geothermal when I build my house. It’ll be a matter of economics – how much will it cost to drill a well, can we just do a subsurface install, etc – that determines if it goes forward or not, but geothermal seems like a very green, very efficient way to provide heating and cooling. I’m keen to see how feasible it will be for a house in central Ohio.

  2. terra Says:

    I’ve heard that Iceland uses geothermal to a large extent, and it’s so warm that shop owners leave their doors open in the winter to welcome customers.

    I’m a big fan of solar, but geothermal has amazing potential. Let’s see a little R&D grants from the government. What a great way to help the environment, and ease the burden from consumers so they can spend their $$ elsewhere. (Although if there is a geothermal plant, consumers may still have to pay the provider, but not as much as our current electricity/natural gas monopolies.) Additionally, new geothermal systems would create new jobs!

  3. terra Says:

    p.s. I know electric and natural gas aren’t technically monopolies.

  4. Brian Says:

    There is a nifty little site called Our Cool House where a couple document the construction of a passive solar, geothermally heated home in Maryland. It’s pretty cool, and they provide tremendous detail into the design, construction, and operation of their home. Including real-time systems data!

  5. terra Says:

    I will definitely check that out.

    Last night I watched Green Energy TV (link in the sidebar). It was amazing. They build “Earthships” which reuse everything! They essentially use geothermal heat and cool, solar panels, and build intelligently. Rainwater was used 4 times, and the walls were made of old car tires stuffed with dirt to hold heat.

  6. Brian Says:

    I’m keen about earthships, but the wife would never approve. Deviating too much from “normal looking” is just not acceptable.

    But rainwater collection, radiant heat, unobtrusive solar panels, and a well-insulated, draft-free house are all acceptable.

    The ironic thing is we have a good amount of land out in the country a bit, so building a non-conventional home wouldn’t be a problem at all. I’d just as soon build a massively earth-sheltered home for both environmental and storm damage purposes (it’s awfully hard for a tornado to do a lot of damage to a home that’s mostly below ground).

  7. [...] solar heating as the concrete floors absorbed heat from the sun to warm the house. There are also 4 geothermal wells about 150 ft deep that provide radiant floor heating. Solar tubes (pictured) provide excellent [...]

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