The Basic Science of Geothermal Heating and Cooling

Plenty of people here in Western Montana, Montana, have engaged Ground Source Systems, Inc. to transform their homes into geothermal homes. Still suspicious of geothermal heating and cooling yourself? Comprehending some of the science behind it – and the mechanics as well – may help.

We’ve written elsewhere about the rewards of geothermal heating and cooling. It’s quite sufficient to say here that few other methods of maintaining apleasant home environment all year long are as efficient, dependable, or economical, particularlly when you size up the energy savings.

Here’s how geothermal works that magic.

Thar’s Gold Heat in Them Thar Hills!

We tap the earth for precious metals. We tap the earth for oil. Now, more than ever, we’re tapping the earth for a resource no doubt just as valuable to most of us: the energy to heat and cool our homes that doesn’t call for oil.

You see, just under the earth’s crust – that would be, oh, say, 33,000 feet under our feet – is a mantle of magma. This is a molten and semi-molten brew, primarily of silicates, in which temperatures run from 1300 degrees Fahrenheit to 2400 degrees Fahrenheit and hotter the deeper you go (not that you’d want to go there!). What this does is keep the ground immediately under the earth’s surface at a reasonably constant year-round temperature of between 45 and 75 degrees Fahrenheit. So? Underground temperatures in Western Montana (and most places stateside, in any event) are warmer than the ambient air above ground in Winter and cooler than the ambient air above ground in Summer.

Time to Get Pumped!

This, then, is what geothermal heating and cooling systems do: they transfer heat from the ground  to your home or heat from your home to the ground, as the season dictates. Either way, your home is maintained at an optimal temperature to keep you and your family comfortable all year long.

The apparatus that performs the transfer is a geothermal heat pump. It continuously circulates water or some mixture (typically antifreeze) between your home and loops of piping (typically fashioned of polyethylene, high-density polyethylene, PVC, or CPVC) buried in the ground. In Winter, the liquid is cold when it enters the ground. As it courses through the loops, it sucks up heat from the earth and is returned to your home warm. In Summer, the process is reversed: warm liquid is brought into the loops, where it takes in the cooler ground temperatures before it’s returned to your home. Need details? You’ll find more specific information on ground loops here.

The salient point is that geothermal heating and cooling systems don’t produce energy. They aren’t like central heating systems, which generate heat themselves. Instead, geothermal systems heat and cool your home by putting to use the energy already amply available beneath the earth’s surface. That’s why geothermal systems are not only quieter but also considerably more reliable, need less maintenance, have significantly longer lifespans, and are more environmentally friendly than standard HVACs. That’s also why, in the end, you’ll save considerably more more money by going geothermal.

Curious now? Get together with Ground Source Systems, Inc., your Western Montana geothermal heating and cooling professional, today.