People looking for cost-effective and durable heating and cooling systems for their homes normally turn to the geothermal system. Because of its energy efficiency, this type of heating system is popularly used in many homes, businesses and schools. Geothermal originally comes from two words – “geo” meaning earth and “thermal” meaning heat. With this, a geothermal system thereby utilizes the earth’s huge supply of heat in the soil.
Geothermal heating systems are also known as ground-source heat pumps that draw a steady supply of heat energy from the soil and move it through a home or building. The three major benefits of this type of system are its energy efficiency, low cost and ability to lessen pollution. The Environment Protection Agency (EPA) in the U.S. says a geothermal heat pump can save homeowners 30 to 70 percent on heating and from 20 to 50 percent in cooling costs over the traditional systems.
Ground-source heat pumps generally move heat using a network of tubes called “closed loops.” These loops (vertical or horizontal) contain either water, refrigerant or an anti-freeze solution which run through the ground and absorb the earth’s energy to deliver heating and cooling directly to the house via heat exchangers. Once the liquid is heated, they are pumped back through the system into the house. After passing through the home and transferring its energy, it goes back to the loop system and the process is repeated. During summer, the system works in reverse mode to provide cool air to homes.
There are primary and secondary loops that play major roles in geothermal heating systems. Cheaper plastic tubing can be used for secondary loops as they are not pressurized and require the use of less refrigerant which are expensive.
Meanwhile, the energy efficiency of ground-source heat pumps is highly valuable to many homeowners. Firstly, they can reduce the use of electricity by up to 70 percent compared to the traditional systems. Secondly, they utilize to its fullest advantage the thermodynamic of a heat transfer fluid. This allows the ground-source heat pump to provide more heat energy output. Thirdly, being able to work on a cooling mode during the summer makes the pump more energy efficient for cooling compared to a regular air conditioning unit. Additionally, when a desuperheater is installed, a ground-source heat pump can move energy to a hot water tank thereby providing free hot water to homeowners both in the summer and winter seasons.
Cost-wise, although a ground-source heating system may initially cost you thousands of dollars, the long-term benefits should be a priority. In fact, it can serve your needs from 20 to 30 years with less maintenance. And once installed, homeowners can enjoy lower monthly energy bills for a long time.
Geothermal heating dates back to the Roman era when Romans used the system in heating their buildings and spas. During that time, they used hot water and hot steam sources found near the earth’s surface. By using this system known as geothermal district heating, it is possible to distribute hot water or steam to several buildings. This same method has long been utilized in other parts of the world.
How Geo-Thermal Works
Geothermal heating is one of the most commonly used types of system in many homes and buildings. It is more preferred than the other systems because of the many benefits it provides to families and building occupants. A major feature of this heating unit that gives it the edge is its being environment friendly.
A study by the U.S. Environmental Protection Agency found that geothermal energy systems can lower energy consumption and other emissions from 23 to 44 percent, can reduce carbon dioxide emissions and incurs the lowest operating and life cycle costs. In addition to these, less maintenance is required because of its fewer mechanical parts most of which are installed underground and with the absence of condensing units in its exterior like air conditioners do, this heating system produces less or no noise at all when turned on.
A geothermal heating system has two types – the closed loop and open loop. The closed loop type makes use of horizontal or vertical pipes where heat is transferred to and from the ground while the open system pumps water from a well or other water source to the heat exchanger and then back to the source. A typical loop system for the closed type is estimated to last for about 50 years. Each system is composed of three major parts – a ground loop involving pipes buried underground, the heat pump installed inside the house and a heating and cooling distribution system also known as ductwork. The pipes are made from durable materials such as polyethylene and copper.
Geothermal heat pumps work in a similar fashion as the regular heat pumps. The only difference is that it uses the stable heat beneath the earth’s surface to provide hot and cool air as well as hot water. Temperature below the ground is constant all throughout the year with temperatures ranging from 45 to 75 degrees Fahrenheit and this makes underground or geothermal heat a very reliable source of energy. In fact, studies have confirmed that around 70 percent of the energy used in a geothermal heat pump is renewable from the ground.
Unlike the conventional heating system that burns fuel, a geothermal heat pump during winter time gathers heat from the earth and brings it to your home. The natural heat is collected in the loop or a series of pipes and is then carried to the house by water or other types of fluid such as an antifreeze solution. As it reaches the home, a compressor that functions via electricity and a heat exchanger release the geothermal energy at a high temperature. The hot air is eventually distributed to the different rooms in the house through ductwork similar to a regular forced-air system.
This type of system can also act as a cooling unit during the summer season. The process, however, is reversed. When the weather is hot, the underground loop extracts excess heat from the house so it can be absorbed back by the earth. This can be compared to how a refrigerator cools the food inside it that is, by drawing heat from the inside.
