The Basic Science of Geothermal Heating and Cooling

A number of people here in Wilmington, North Carolina, have engaged O'Brien Service Company to transform their homes into geothermal homes. Still wary of geothermal heating and cooling yourself? Comprehending something of the science behind it – and the mechanics as well – would undoubtedly help.

We’ve written elsewhere about the perks of geothermal heating and cooling. It’s quite sufficient to say here that almost no other manner of maintaining a climatically comfortable home environment year-round are as efficient, dependable, or economical, especially when you gauge the energy savings.

Here’s how geothermal makes that a reality.

Thar’s Gold Heat in Them Thar Hills!

We dig in the earth for precious metals. We dig in the earth for oil. Now, as never before, we’re tapping the earth for something no doubt just as valuable to the majority of us: the energy to heat and cool our homes that doesn’t necessitate oil.

You see, close beneath the earth’s crust – that would be, oh, say, 33,000 feet under our feet – is a layer of magma. This is a molten and semi-molten mixture, for the most part made up 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 does is keep the ground immediately under the earth’s surface at a relatively consistent year-round temperature of between 45 and 75 degrees Fahrenheit. Meaning? Underground temperatures in Wilmington (and most places 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, as the season dictates. Either way, your home is maintained at an optimal temperature to keep you and your family comfortable year-round.

The mechanism that handles the transfer is a geothermal heat pump. It continuously circulates water or some blend (typically antifreeze) between your home and loops of pipe (typically fashioned of polyethylene, high-density polyethylene, PVC, or CPVC) installed 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 reintroduced to your home warm. In Summer, the process is reversed: warm liquid goes into the loops, where it’s cooled by the cooler ground temperatures before it’s returned to your home. Need details? You’ll find more thorough information on ground loops here.

The primary 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 a lot more dependable, need less maintenance, have significantly longer lifespans, and are more environmentally friendly than standard HVACs. That’s also why, ultimately, you’ll save a great deal more more money by going geothermal.

Curious now? See O'Brien Service Company, your Wilmington geothermal heating and cooling authority, today.