Geothermal cooling is the use of the earth in a system that allows the regulation of temperature. It is commonly used in cooling domestic houses in regulating the temperature especially during summer. It uses the earth as a heat source and at the same time as a heat sink.
Underneath the frost line is the layer of the surface of the earth which has a steady temperature of 6 C. This temperature is sufficient to provide energy to regulate the temperature. A geothermal device is used to draw the heat energy from the ground.
The layer of the earth benefit the frost line is very vast so surface temperature has negligible effects to it. This makes it possible to install a pump under the ground which can effectively pull cool sustaining temperature from the earth.
Geothermal cooling systems work by moving heat unlike a furnace which converts chemical energy into heat. It has three major components which are the geothermal heat pump, an earth connection, and a distribution system.
The geothermal heat pump is the one responsible for moving the heat from the establishment to the fluid in the earth connection.
The distribution system is used for delivering cooling to the house. In residential use, conventional ductwork is used in geothermal systems in order to distribute cold air and to provide humidity control. A less commonly used one is the water-to-water heat pump which has fan coil units, radiators, or under-floor circulating pipes to distribute cool temperatures to the house. It is important that the ducts are sealed, well-constructed and properly sized in order to maintain the efficiency of the system. The ducts must also be well insulated. If possible, they must be placed inside the building's thermal envelope.
The earth connection is composed of a series of pipes that are buried underground. It connects the geothermal heat pump to the earth. The series of pipes is also called a loop. There are two types of loops that are commonly used. One is the closed loop and the other is open loop. It is made of high density polyethylene pipes.
The open loop system is the simpler system. It has two wells. Through one well, it draws ground water from an aquifer. The water then goes to the geothermal heat pump heat exchanger and then it goes to the second well where it is discharged to the aquifer again. The open loop system is ideal for lots that are not too big because closed loop systems need larger land area. However, open loop systems have a problem with ground water chemical conditions because these conditions can lead to damaging the geothermal heat pump's heat exchanger. Precautions are needed to keep gases such as carbon dioxide in solution in the water.
The closed loop system is the less common one. However, it is becoming more and more popular nowdays. This is because they are economic, efficient and reliable if they have been properly installed. In this system, water and antifreeze solution is allowed to circulate through the buried pipe keeping. The closed loop system is more environmentally friendly as compared to the open loop because the water used in the closed loop does not go out of the loop and contaminate the external environment. There are two kinds of closed loop system. There are the horizontal loops and there are the vertical loops.
The horizontal closed loop is more ideal when the land area of the owner is large. It is cheaper to install for small installations. Installing this one is also better for new construction. Six pipes which have parallel connections are usually buried in each trench.
The vertical closed loop, on the other hand, is preferred for situations where there is limited land area such as buildings and houses in urban areas. This is because horizontal closed loops are prohibited and also vertical closed loops have minimal disturbance to existing landscaping. Therefore, vertical closed loops are more common especially in the urban area.
Some less commonly used loops are slinky loops and pond loops.
In order to maximize the efficiency of geothermal cooling systems, people should consult and hire professionals who can assess their space and see what kind of earth connection or loop to use.
Geothermal cooling systems have a lot of advantages over the conventional air-conditioning system today. Geothermal cooling systems are efficient, economic, comfortable and environment friendly.
Geothermal heat pumps are more efficient than air source heat pumps. This is due to the temperature of the earth below the frost line is uniform year round as compared to atmospheric temperature.
Geothermal cooling systems are more economic. It is true that the installation is more expensive; however, their energy consumption will be reduced by up to 70% which means that people can save more money in the long run.
It is also more comfortable to use because it has lower temperature increments which means that the temperature can be controlled and adjusted more easily than the conventional air-conditioning system. It can also cool the air more evenly and more gradually.
This technology is also one of the solutions to the problem on greenhouse gasses because geothermal heat pumps do not need to of burning fuel to control the temperature. It moves heat instead of generating it.