While regular heat pumps use the air to transfer heat either into or out of your home, a geothermal heat pump uses the earth to transfer heat. Just a few feet below the surface, the ground remains at a relatively consistent temperature that is warmer than the air above it during winter and cooler during the summer. A geothermal heat pump utilizes these temperatures to heat and cool your home.
Geothermal heat pumps are the most efficient way to heat and cool your home. In the winter, heating costs can be reduced by around half. Some geothermal heat pumps also have a “desuper heater” that can heat household water as well. During the summer, heat taken from inside your home is used to heat your hot water for free. The heating efficiency of geothermal heat pumps is measured in COP (coefficient of performance) and the cooling efficiency is measured in EER (energy efficiency ratio). They use 25-50% less electricity and can reduce energy consumption up to 44% compared to regular heat pumps.
The installation price of a geothermal heat pump is much higher than that of a conventional air source heat pump but the return from tax credits and energy savings make up for it. You will see a return between 5 and 10 years. The system life of a geothermal heat pump is about 25 years and the piping can last between 25-50 years.
Geothermal heat pumps can either use a closed or open loop system. The type of piping to be used for your home is determined by the characteristics of your land. Factors such as the composition of your soil, ground water availability and how much land you have available will determine which type of looping is best for you.
Closed loop systems circulate an antifreeze solution through a closed loop that is buried in the ground or submerged in water while a heat exchanger transfers heat between refrigerant in the heat pump and the antifreeze solution. There are three types of loops that are used:
- Horizontal loop systems are the most cost effective for residential applications. This type of looping requires trenching of between 3 and 6 feet deep.
- Vertical loop systems are typically used for commercial buildings and schools because they require less land area than horizontal. It is also used when the soil is too shallow for trenching.
- Pond/Lake loop systems are the lowest cost as long as the site has a large enough body of water. The water source must meet certain criteria.
Call the experts at Davis Heating & AC in Jacksonville, NC for more information on geothermal heat pumps or any other type to heating and cooling system. We offer installation, repair, indoor air quality products and preventative maintenance for your HVAC system.