Archaeological evidence highlights geothermal energy as one of humanity’s oldest energy sources.  Evidence suggests that for ten thousand years or more, indigenous people of North America used geothermal energy within their healing rituals in hot springs.  Similar evidence was found in Greece and Rome. The hot springs became a “hotbed” of commerce because of the traffic of trade and diplomacy, while early inhabitants of Earth made use of the medical beliefs that soaking in the hot springs brought.  

 

What is Geothermal?

The prefix Geo– comes from the Greek word meaning “earth”, and the base word therme– also comes from the Greek origin meaning “heat”.  So, in layman’s terms, it means:  heat energy from the earth.  The energy comes from a renewable source of thermal energy from within the earth’s crust. The heat is continually produced below the earth’s crust, where there is a layer of hot and molten rock called magma. Natural radioactive materials of uranium and potassium decay, creating continuous heat at that layer. 

 

Where is Geothermal Energy Found?

Geothermal energy can be captured with:  geothermal springs, direct use of geothermal heat and the conventional method of ground-source heat pumps. GSHPs,  or as they are sometimes referred to as a GeoExchange, have been in use since the 1940s.  The constant temperature of the shallow earth thermal storage is used to level out the highs and lows of extreme temperatures. So, by using geothermal energy it is able to essentially cool homes in the summer and heat homes in the winter by exchanging this below ground temperature to provide a better energy balance. In layman’s terms, geothermal energy is the sun’s energy stored in the earth’s crust.

Depending on which part of the country you live in, this temperature may vary. The average temperature in your area throughout the year will be a very close estimate as to what your earth’s ground temperature should be. The ground absorbs 47% of the sun’s heat.  Southern PA, MD, WV and parts of Northern Virginia will experience a temperature between 56 and 60 degrees Fahrenheit. 

 

How Does Geothermal Heating and Cooling Work?

GSHPs are electrical units, much like a refrigerator or an air-to-air heat pump.  The Ground Source Heat Pump utilizes the constant temperature of the earth to capture very high efficiencies for heating and cooling.  Unlike refrigerators and air-to-air heat pumps, which operate off of the current air temperatures, the GSHP can maintain steady efficiencies through the hottest days in the summer and the coldest days in the winter without having to go through a defrost cycle.  Typically, GSHPs are connected into two main circuits, a closed loop or an open loop.  An open loop uses groundwater via a submersible pump, and this is discharged once the water is utilized.  A closed loop system circulates water or an antifreeze solution throughout a series of loops to utilize the constant earth temperature. 

What is included with a Ground Source Heat Pump?

An underground heat collector:  A GSHP uses a series of connected pipes that are buried in the ground near the building.  The loop can either be either vertical or horizontal.  That geothermal loop will circulate either water or that antifreeze solution that was mentioned earlier.  Types of geothermal loops:

Horizontal Loops –  This is used when there is ¼ to ¾ of an acre of land available.

Vertical Loops –  Used when there is limited space available.  3-5 holes are drilled within about 15 feet of one another. 

Pond/Lake Loops –  When there is an adequate sized body of water close to the home. 

Open Loops –  When there is an abundance of a quality water supply. 

The Use of a Heat Pump:  When ambient temperatures (room temperature) require heating or cooling, a GSHP will obtain energy from the underground collector fluids, use this collection of energy via a heat pump process, and then transfer it to the building. 

Heat Distribution:  This is where the heat is distributed throughout the building, usually through the form of ductwork.  The opposite occurs from Cooling Distribution. 

What are the Benefits of Geothermal Energy?

How would you like to live comfortably?  What about saving money, would you like to do that?  How about if you could help save the earth and reduce your carbon footprint?  I bet you probably nodded your head a couple of times there.  With geothermal energy, you can answer those three questions with certainty.  

Renewable Energy:  That steady heat flow continues to be supported by decaying radioactive elements. 

Cost Saving:  Geothermal energy can cut energy consumption from 20% to 50%. A geothermal well helps to balance out fluctuations in energy rates.  For every one dollar of energy purchased, a geothermal well system can provide 4-5 dollars in energy with assistance from the earth.  ($1 of energy purchased + $3-4 from the earth=$4-5 dollars of energy for your home.)

Reliable Energy:  Geothermal energy is not weather or season-dependent, so it’s always “on”, unlike solar or wind energy. 

Better for the Environment:  Extracted from the earth, doesn’t burn any fossil fuels and has little emissions. 

Tax Credits and Incentives:  A federal tax of 30% has been extended through December 31, 2032.  Then, the incentive will be lowered to 26% in 2033 and then 22% in 2034.  There are also local incentives that may apply to your area. 

 

Although geothermal energy has been around for ten thousand years, a homeowner doesn’t have to wait quite that long to see a return on investment.  Typically, a homeowner will see savings that equate to their investment within 2-10 years after installation. Want to save money, live comfortably, and protect the earth?  Then, a geothermal well might be the right fit for your home.  With tax credits and incentives, there has never been a better time to Feel Better About Your Energy.