Most homeowners are aware of energy saving ratings that make appliances such as dishwashers, refrigerators, and air conditioners more appealing to purchase. Between government kickbacks and lower utility bills replacing outdated items, with newer ‘green’ models, pays itself back. Taking that step further, there’s a kind of energy, stored in the earth, that fuels the home – geothermal heating.
Some of the first forms of geothermal heating were the hot spring bathhouses from as early as the 3rd century B.C. A more modern version of geothermal heating came to fruition in the 1940’s with the advent of the heat pump that could take this natural resource and turn it into a usable convenience. Here are some tips on how we use geothermal heating in homes today:
A Constant Resource
In all sorts of climates around the world, there is a natural and constant temperature in the earth’s surface. In the winter, the earth’s undersurface is warmer than the air above the surface. In the summer, the ground is cooler. To reach this constant temperature (ranging from 10°C to 25°C) you must drill down below the frost line so that the geothermal heat pumps can use the core warmth to heat the house and warm the water.
A geothermal heating system normally consists of a system of pipes buried underground and an indoor handling unit. The buried pipes, known as an earth loop, transfer the heat from the underground to the house. You can bury the polyethylene pipes that make up an earth loop horizontally or vertically.
Works Like a Conventional Furnace
An interesting thing about geothermal heating is that it operates in much the same way as a conventional furnace. The house uses ductwork and air return but instead of gas or electricity, the fuel source is the earth. Even when geothermal energy is used to cool the house, the warm air is sent through the heat pump either back into the ground or even better to heat a hot water tank.
Electricity Powers the Heat Pump
Unlike ordinary heating and cooling systems, geothermal heating and cooling systems do not burn natural fuels, such as coal or gas, to create warmth; they simply move heat from and to the earth. Typically, electric power is used only to operate the unit’s fan, compressor, and pump.
The heat pump carries a combination of water and refrigerant through the cycle between the house and underground. Some geothermal heating systems use a closed loop system, which means that the fluid stays contained within the system and simply does ‘laps’. Most houses use a horizontal loop system that runs horizontally under the surface of the earth, but not as deep into the earth. In commercial buildings or apartments a vertical system is used which is more expensive because it protrudes deeper into the earth.
Savings Are Real
Because they are more unique and specialized, a geothermal heating system will cost more to implement than replacing a standard furnace. That being said, homeowners can legitimately expect savings between 30% and 70% on their utility bills. In addition, once the system is in place, it’s virtually maintenance free, and the heat pumps have a life expectancy of 20+ years. Combined with tax credits for implementing a geothermal heating system, making the change is very financially worthwhile.
In a weird way geothermal heating is an old, yet new technology. The more people that decide to harness the earth’s natural resources for their home’s energy, the more services that will pop up and the lower the prices will become – a win-win situation.