Every day, the sun is constantly beaming solar energy towards the earth, and the idea of harnessing this energy is an attractive one. When people think of using energy from the sun, solar panels are usually the first thing to come to mind. But one of the most promising ways to get energy from the sun, oddly enough, involves digging down rather than looking up: ground source geothermal energy.
What does geothermal energy have to do with the sun?
There are actually two types of geothermal energy. One pulls energy from the heat produced in the core of the earth; this has the potential to generate a lot of energy, but it's also more difficult to access because of the depths involved.
The second type, ground source heat, involves energy from the sun rather than the earth's core. Since the sun is continually shining on the earth, the ground absorbs a great deal of solar radiation and stores that warmth near the surface. While the air temperature in most areas varies a great deal from day to night and from season to season, the temperature a few feet beneath the ground stays much more constant.
How does a home geothermal heating system work?
Ground source geothermal heat pumps aren't all that different from conventional heat pumps: refrigerant is pumped through looped pipes to transport heat from one place to another. Air conditioners work this way, pulling heat into the system in your home and then releasing that heat outdoors; heating systems do the opposite.
Geothermal heat pumps do the same thing, but rather than draw in or release heat through outdoor pipes, the pipes run from your home down through the ground. This means more efficient heating and cooling because of the stable temperatures below the ground.
Why would I want a geothermal heat pump?
According to the U.S. Department of Energy, these systems can be over twice as efficient as air-source heat pumps. And although they may cost more to install, this added efficiency means they pay for that difference within a decade with reduced energy costs.
The advantages over heating sources like propane and natural gas are more pronounced. Heating with these fuels contributes to air pollution; as many cities increase the regulation of heating oils to reduce pollutants, costs increase.
If you are interested in cleaner geothermal heating for your home, you may also be able to get tax incentives to lower the initial costs. Through the end of 2016, for instance, Energy Star qualified heat pumps through a company like Hayes Heating & Cooling will qualify you for a 30% federal tax credit, and some state and local incentives also exist; talk with your local government or a tax professional to make sure you find all the credits you could be eligible for.