The Energy Beneath Our Feet

Malcolm Gladwell, the New Yorker staffer and author of the bestselling books, The Tipping Point and Blink, blogs about the geothermal heating system in his parents' home in Ontario. Actually, his father does most of the explication here, with a nice introduction that begins:

Geothermal heating and cooling is based on one simple fact: that 6 feet down in the ground the temperature is the same—between 50˚F and 60˚F- the whole year round. This means that it is relatively cool in the summer, and relatively warm in the winter. Geothermal heating is thus quite different from solar heating: solar heating works worst when you most need it--in the cold, cloudy, snowy conditions of winter; the source for geothermal heating and cooling is not affected by the weather. For geothermal cooling, all one needs to do is to circulate water in a pipe through the ground to cool it, and use this cool water to cool the air pumped through the house in the heating ducts.

Such systems are often referred to as heat pumps or heat exchangers, although as noted above, they are also adept at cooling as well, and far more efficient than conventional air conditioners.

One thing the Gladwells don't mention is that, in mild climates, so-called air source heat pumps are another good option for home heating and cooling. These systems use the difference between indoor and outdoor air temperatures to regulate the home's ambient temperatures. As with geothermal heat pumps, there's no fuel combustion involved. And, according to the Department of Energy, "When properly installed, an air-source heat pump can deliver one-and-a-half to three times more heat energy to a home than the electrical energy it consumes." So, given that, why isn't the Energy Department actively pushing heat pumps as one of the solutions to our growing energy crisis? Beats me.

As Gladwell concludes:

One of the frustrating things about the current discussion over our dependence on imported oil is the persistent notion that real solutions will require some future technological breakthrough. I think we have a lot of the answers. We just haven’t made consumers and public officials aware of them.

Anyone out there have personal heat-pump experience? How does the system work for your home?

Update: I just remembered: George W. Bush uses geothermal heating and cooling down on the ranch in Crawford. Don't believe me? Here's a document (pdf) from the National Renewable Energy Lab to substantiate the claim. The "Texas White House" is actually a fairly eco-sensitive spread, with a passive solar design, wastewater recycling and rainwater collection. The home was designed by green architect David Heyman. So,...maybe Gladwell needs to rethink his conclusion. It's not that "We just haven’t made consumers and public officials aware of them." It's more like they've been keeping them to themselves.