The ground serves as a large storage of solar energy which can be utilized as a source of heat during winter season or serves as heat sink during hot summer days. The ground has the ability to regulate the temperature of buildings that stand on it.
Also known as Geothermal heat pump, Ground source heat pumps extract geothermal heat from the earth to supply clean and energy-efficient way to heat buildings without releasing any carbon emissions. This is powered by electricity to efficiently generate up to five times as much heat energy for every electricity used. Ground source heat pumps can be suitable to different buildings and heating requirements.
Although it requires electricity to drive up the compressors and circulation pumps, they regenerate more energy than they actually use and can be integrated into other equipments to make it renewable. Ground source heat pumps operate more efficiently with low temperature heating distribution systems like underfloor heating. At 35°C, for every one unit of electricity used in ground source heat pumps, 4 units of unit energy are generated. For an effective environmental solution, green electricity can also be purchased.
It is commonly used in Switzerland, Germany, Sweden and North America for many years now. Installing heat pumps may cost more than typical heating systems; however, the costs to maintain it is relatively low and it guarantees a dependable, safe and emission-free heating for more than 20 years.
Types of Collectors
There are two types of collectors: open loop and closed loop.
Open Loop. Water normally travels through the ground in aquifers (between sandstones, broken rock and gravels) and will follow the ground’s temperature where it flows. Drilling holes in the aquifer will divert the water to serve as a source of heat. To know its viability, a special hydrogeological survey is conducted to conclude the longevity and extent of the resource. Due to its complicated requirements and numerous uncertainties like air locking, unexpected geological conditions, falling water table and degradation of the boreholes, experts highly recommend closed loop systems more. However, if there are accessible wells that supply water, open loop systems can be effectively installed. In areas like London, elevated water tables contribute as water source for heat pumps where water is extracted from the original water course.
Closed Loop. Like open loop systems, closed loop may still suffer air locks and may need protection during and after they have been successfully installed to eliminate blockages and pipework falls. The amount of heat energy transferred between the pipe and the ground will be based on the thermal qualities of the ground, the materials used around the pipe, the fluids traveling in the tube and the number of hours yearly the heat is extracted.
Installation
You need to hire someone who has extensive skills and knowledge in designing and installing ground source heat pumps. A ground source heat pump may not function well unless it is integrated in an effective design by an expert who knows the needs of the building and the geological conditions of the place.
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