Why choose a geothermal heating system?

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    Tony Silverio, center, explains the economics of geothermal heating and cooling to Alexandra Marks and Martin Sheridan.
    Joanne Ciccarello/Staff/The Christian Science Monitor
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As an indication of how completely antediluvian I was in terms of my Green IQ (a term I thought I’d just made up, but is actually all over the place, I had not even known that geothermal heating and cooling was a viable option in the Northeast until after we’d already bought Sheep Dog Hollow.

Martin and I were standing outside the house with Dale King, the previous owner who is also our lead builder and who lives down the road. (More on Dale later.) I was talking about how we’d like to renovate as “greenly” as possible but also maintain the historic nature of the house.

I didn’t like the idea of having huge, high tech solar panels glinting on top of the elegant old white clapboard frame.

“Why don’t you look into geothermal?” he suggested.

“We’re not in Iceland,” was my first thought, which I fortunately kept to myself. Instead, I took his advice and was stunned not only by how much common sense geothermal energy makes, but also that there’s a nascent but fast-growing geothermal industry here in the United States.

In a nutshell, geothermal energy consists of using the constant temperatures stored naturally underground to heat and cool your house.

You drill a few wells, run pipes through them, and then circulate a liquid through those pipes. As the liquid travels through those pipes underground, it heats up to at about 55 degrees F. – the steady temperature that the earth naturally generates between 10 feet and 300 feet down. You then hook those pipes up to a heat pump in your basement.

In the winter, the heat pump compresses the liquid to increase its temperature to about 75 degrees F., which is then used to heat the house. In the summer, the circulating 55 degree F., temperatures are used to air condition the house.

You do need an energy source to run the heat pump – you can use electricity or natural gas, but other than that, the main source of your heat and air conditioning is the ground beneath you.

Say goodbye to that oil company and the thousands of dollars you pay them each winter to keep your house warm.

I immediately began researching local geothermal companies and was delighted to find several in the area. I contacted them and got several quotes. My first reaction upon seeing them was “YIKES!” as I’ve mentioned before.

The initial upfront costs for just the equipment ranged from $55,000 to $75,000. And then there’s the cost of drilling the wells. Our first estimate for that was around $28,000. We’re talking $20,000 to $30,000 more than a high-efficiency oil burner system for a house of a comparable size.

From an economic standpoint, in the short term at least, it made sense to forego my geothermal dreams.

But I couldn’t get over how much common sense geothermal made to me – using the natural heat underground to heat your house, versus depending on a very expensive fossil fuel (also from underground) that was probably drilled thousands of miles away in a manner that is not sustainable and the daily use of which contributes to global warning.

I then called the geothermal contractor who came with the highest recommendation from other local contractors and from our well driller. His name is Tony Silverio.

He sat with Martin and me for more than an hour and explained the pros and cons of geothermal (which I’ll get into in the next blog). but the bottom line, he said, was that with a geothermal system's annual heating and cooling costs are estimated to be between 65 and 70 percent less annually than a traditional fossil fuel system.

Then to help soften the blow of the initial up front costs, there are federal and state tax credits. When you take advantage of them, what looks like an outrageously expensive system becomes a more moderate one.

This was confirmed in Interesting Energy Facts:

Geothermal energy can provide not only 100 percent of home heating, but also air conditioning and hot water, and it requires no additional use of oil, natural gas [although you can use it] or any other fossil fuel. And the payback on geothermal is more than acceptable. If you consider the 30 percent federal tax credit, payback usually takes less than five years in new construction and somewhere around seven years for retrofits. This translates to gigantic 15 percent annual return on investment simply by installing a geothermal system, which is really a number from which many other energy sources are still far off.
The logic in this whole story is quite simple, namely homeowners pay back the investment with the money they would have paid to oil or gas company. After payback, the savings continue with an average return of more than 65 percent – percentage that is likely to be even higher as fossil fuel prices are very likely to increase after recession is over.

OK, I was sold. But there are limitations and drawbacks to using a geothermal system, which I’ll talk about next.

Editor's note: Alexandra Marks will be blogging twice a week about her green and budget-friendly restoration of a 1902 farmhouse in Connecticut. See a photo gallery of the early days of the project by clicking here. You can read all she's written about the project so far by clicking here and then looking for Sheep Dog Hollow under Topics on the right side of the page.

You'll find numerous articles about the environment at the Monitor’s main environment page. Also, check out our Bright Green blog archive and our RSS feed.

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