The Basic Science of Geothermal Heating and Cooling

More than a few residents here in Portland, OR, Oregon, have sought Total Energy Concepts to make their homes geothermal homes. Still need persuading about geothermal heating and cooling yourself? Understanding a smidgen of the science behind it – and the mechanics as well – would probably help.

We’ve written elsewhere about the rewards of geothermal heating and cooling. Suffice it to say here that hardly any other methods of maintaining apleasant home environment all year long are as efficient, dependable, or economical, particularlly when you take into account 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 a heretofore unparalleled degree, we’re tapping the earth for something undoubtedly just as valuable to the majority of us: the energy to heat and cool our homes that doesn’t entail oil.

You see, right below the earth’s crust – we’re talking no more than 33,000 feet under our feet – is a layer of magma. This is a molten and semi-molten mixture, principally 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 relatively stable year-round temperature of between 45 and 75 degrees Fahrenheit. So? Underground temperatures in Portland, OR (and essentially everywhere 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, in accordance with the season. Either way, your home environment stays at an optimal temperature to keep you and your family comfortable month after month.

The device that accomplishes 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) installed in the ground. In Winter, the liquid is cold when it enters the ground. As it travels through the loops, it takes in 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 thorough information on ground loops here.

The salient point is that geothermal heating and cooling systems don’t produce energy. They’re not like central heating systems, which generate heat themselves. Instead, geothermal systems heat and cool your home by employing the energy already abundantly 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 old-school HVACs. That’s also why, over time, you’ll save lots more more money by going geothermal.

Curious now? Get together with Total Energy Concepts, your Portland, OR geothermal heating and cooling professional, today.