The Basic Science of Geothermal Heating and Cooling

A good many homeowners here in Rochester, Minnesota, have signed on with Earth Energy Heating & Cooling Inc. to upgrade their homes to geothermal homes. Still need convincing about geothermal heating and cooling yourself? Understanding some of the science behind it – and the mechanics as well – may help.

We’ve noted elsewhere the virtues of geothermal heating and cooling. It’s quite sufficient to say here that hardly any other methods of maintaining a comfortable home environment throughout the year are as efficient, trustworthy, or affordable, especially 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, more than ever, we’re tapping the earth for a treasure no doubt just as valuable to many of us: the energy to heat and cool our homes that doesn’t entail oil.

You see, close beneath the earth’s crust – we’re talking no more than 33,000 feet under our feet – is a mantle of magma. This is a molten and semi-molten brew, predominantly 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 relatively stable year-round temperature of between 45 and 75 degrees Fahrenheit. So? Underground temperatures in Rochester (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!

The job, then, of a geothermal heating and cooling system is to|Underground temperatures being what they are, then, it’s the task of a geothermal heating and cooling system to 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 stays at an optimal temperature to keep you and your family in comfort throughout the year.

The device that effects the transfer is a geothermal heat pump. It continuously circulates water or some mixture (usually antifreeze) between your home and loops of pipe (usually 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 absorbs 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 takes in the cooler ground temperatures before it’s returned to your home. Need details? You’ll find more comprehensive information on ground loops here.

The primary 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 making use of the energy already richly available beneath the earth’s surface. That’s why geothermal systems not only run quieter but also are a lot more reliable, need less maintenance, have much longer lifespans, and are more environmentally friendly than old-school HVACs. That’s also why, ultimately, you’ll save considerably more more money by going geothermal.

Curious now? See Earth Energy Heating & Cooling Inc., your Rochester geothermal heating and cooling authority, today.