Front Yard Geothermal: Anticipation

Written by Mike

Geothermal Vertical Loop[Update 10/12/11: Well, now it looks like next week we are finally getting geothermal... Our driller is a bit behind on some other jobs.]

This Next week I plan to look down a hole 180 feet deep, explode a mud bomb in my front yard, and lose 5,000 pounds.

We're finally getting geothermal.

In case you're not an energy geek, a geothermal heat pump is a system to extract energy from the earth to use for heating and cooling a building. The heat is not from molten lava -- that would be cool, but it's not really practical for a house in Wauwatosa (for info on "hot rock" power generation as well as residential geo, here's the Dept of Energy site). Instead the earth is used as a source of constant temperature. By sending a fluid (mostly water) through loops of pipe in the ground, you can get something relatively warm in the winter and cool in the summer. The heat pump amplifies the winter warmth for heating, and the summer coolness for air conditioning.

By using energy stored up in the earth, a geothermal is very affordable to operate. The only input is electricity to pump water through the ground piping and run the heat pump.

You don't have to go very far underground to reach a constant temperature of 40-50 degrees. However if your fluid is hot or cold (as it will be after coming out of a heat pump), you need to move it a certain distance so it has a chance to reach ground temperature. Here in Tosa we don't have a field or pond run our pipes under. The only direction we can go is down. In our case, 180 feet down, three times, for a total of 540 feet of double (U-shaped) piping.

I'm told it's a mess. One contractor said, "It's like a bomb going off in your front yard."  We'll find out. I'm still working on the landscaping budget.

And even though running this system will not cost much, you can imagine, putting it in isn't cheap.

So... why?

That's the 5,000 pound question.  5,000 pounds is the amount of carbon dioxide produced by the natural gas we burn in our house every year.  If we can buy renewably generated electricity to run a geothermal heat pump instead, we lose those 5,000 pounds of fossil-fueled greenhouse gases.  Maybe crazy, but to me it's worth it.

If you're starved for entertainment, here's a fun video from the DOE:

Later this week month once it gets going, I'll post some pictures.

[Part 2 in the Geothermal Saga is now available here]

Last Updated on Monday, 24 October 2011 18:57