What is Geothermal Heating and Cooling?
Throughout the Tri-State, we experience seasonal temperature extremes – intense humid heat in the summer to freezing conditions in the winter. A few feet below the earth’s surface, the ground remains at a relatively constant temperature, ranging from from 45°F to 75°F. Like a cave, this temperature is warmer than the air above it during the winter and cooler than the air in the summer. A Geothermal Heat Pump takes advantage of this by exchanging heat with the earth through a ground heat exchanger.
There are three main types of geothermal systems — horizontal, vertical, and pond/lake closed-loop systems. Which one of these is best depends on the soil conditions, available land, and installation costs at the site. All of these approaches can be used for residential and commercial building applications.
This type of installation is generally most cost-effective for residential installations, particularly for new construction where sufficient land is available. It requires trenches at least four feet deep. The most common layouts either use two pipes, one buried at six feet, and the other at four feet, or two pipes placed side-by-side at five feet in the ground in a two-foot wide trench. A coil method of looping pipe allows for more pipe in a shorter trench, which cuts down on installation costs and makes horizontal installation possible in areas it would not be with conventional horizontal applications.
A vertical system is often used when the land area required for horizontal loops would be prohibitive. Vertical loops are also used where the soil is too shallow for trenching, and they minimize the disturbance to existing landscaping. For a vertical system, holes (approximately four inches in diameter) are drilled about 20 feet apart and 100 to 400 feet deep. Into these holes go two pipes that are connected at the bottom with a U-bend to form a loop. The vertical loops are connected with horizontal pipe (i.e., manifold), placed in trenches, and connected to the heat pump in the building.
If the site has an adequate water body, this may be the lowest cost option. A supply line pipe is run underground from the building to the water and coiled into circles at least eight feet under the surface to prevent freezing. The coils should only be placed in a water source that meets minimum volume, depth, and quality criteria.
Geothermal systems offer the highest efficiency ratings, with a 4 to 1 ratio compared to electrical energy. That’s 400% efficiency! With this advantage, the consumer can lower their utility bills significantly, up to 70%. In addition to efficiency, the EPA and the U.S. Department of Energy recognize geothermal systems as the most environmentally friendly way to heat and cool a home.
So if you think that geothermal is the right way for you to heat and cool your home, give Brackett Heating and Air a call, or click below to schedule a free estimate with one of our Home Comfort Specialists.