The Basic Science of Geothermal Heating and Cooling

A good many homeowners here in Seattle, WA, have hired Vaughn Mechanical to upgrade their homes to geothermal homes. Still wary of geothermal heating and cooling yourself? Comprehending a smidgen of the science behind it – and the mechanics as well – would undoubtedly help.

We’ve talked elsewhere about the virtues of geothermal heating and cooling. It’s enough to say here that few other manner of maintaining apleasant home environment whatever the season are as efficient, dependable, or affordable, particularlly when you factor in the energy savings.

Here’s how geothermal makes that possible.

Thar’s Gold Heat in Them Thar Hills!

We mine the earth for precious metals. We drill the earth for oil. Now, to an unprecedented degree, we’re tapping the earth for a treasure undoubtedly just as valuable to many of us: the energy to heat and cool our homes that doesn’t necessitate oil.

You see, close beneath the earth’s crust – no more than 33,000 feet under our feet – is a layer of magma. This is a molten and semi-molten mixture, for the most part comprised of silicates, in which temperatures vary from 1300 degrees Fahrenheit to 2400 degrees Fahrenheit and hotter the deeper you go (not that you’d want to go there!). What this serves to do is keep the ground immediately under the earth’s surface at a year-round temperature of between 45 and 75 degrees Fahrenheit. Result? Underground temperatures in Seattle (and essentially everywhere stateside, as it were) are warmer than the ambient air above ground in Winter and cooler than the ambient air above ground in Summer.

Time to Get Pumped!

What geothermal heating and cooling systems do, then, is transfer heat from the ground  to your home or heat from your home to the ground, in accordance with the season. Either way, your home’s interior is maintained at an optimal temperature to keep you and your family comfortable throughout the year.

The appiance that handles the transfer is a geothermal heat pump. It continuously circulates water or some blend (commonly antifreeze) between your home and loops of pipe (commonly 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 goes into the loops, where it absorbs the cooler ground temperatures before it’s returned to your home. Looking for details? You’ll find more thorough information on ground loops here.

The key 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 not only run quieter but also are considerably more dependable, need less maintenance, have far longer lifespans, and are more environmentally friendly than standard HVACs. That’s also why, over time, you’ll save a lot more more money by going geothermal.

Curious now? Talk with Vaughn Mechanical, your Seattle geothermal heating and cooling specialist, today.