Wow. That's a very cool place. Looks like it could be a pain to heat. And some of it looks like it could be a bit gloomy, too. But it more than makes up for both of those through sheer awesomeness.

Carrington - it does go underground, but the only exponents of geothermal activity remotely close by are Stromboli and Etna, and I'm happy to be out of their way (not exactly out of range - Etna can send it's ashes and reportedly even rocks here, not to mention deeper than standard waves).

Your own backyard has the potential to be an energy source for heating and cooling comfort. Outdoor air temperatures fluctuate throughout the year with the changing seasons. In contrast, ground temperatures about four to six feet below the Earth's surface remain relatively moderate and constant all year. That's because the Earth absorbs 47% of all the heat energy that reaches its surface from the sun. A geothermal system circulates a water-based solution through a buried loop system to take advantage of these constant temperatures. A single piece of equipment has the ability to heat and cool your home, while providing some or all of your home's hot water as well. Geothermal systems can save you 30% to 70% on your monthly utility bills.