With the drive to make renewable energy part of new green structures, solar usually takes the front seat, followed by wind. But we all happen to be standing on another source of renewable energy that is too often forgotten — the ground. Lucy Pullon, who works with a geothermal energy company has provided this guest post on ground-source heating.
Any developers who are planning a new build, such as an office block or residential housing development, should consider implementing ground source heating into their project. For a green, renewable energy source, ground-source heating is easy to install and requires very little maintenance.
How does it work?
A quantity of pipes, referred to as a ground loop, is buried underground. A mixture of water and antifreeze is circulated around this loop, drawing heat from the ground which is absorbed into the fluid. After passing through a compressor, the heat is transferred to the pump and is stored as energy to be used for heating rooms and water. The cooled fluid then returns to the loop to repeat this continuous cycle.
It is normal for the loop to be laid flat or coiled about two metres below the surface. However, if there is not sufficient space available, a vertical loop can be installed in a borehole.
What are the benefits?
Although ground source heating requires electricity to function, to power the pump, it is a renewal energy source, using a fuel that is naturally replenished. The heating provided by this method is usually cheaper than conventional electric heating, and it requires no delivery of fuel, which makes it an ideal solution for developments without a connection to a mains gas supply.
Once installed, the system is very low maintenance, sometimes referred to as a ‘fit and forget’ power supply. It is inexpensive compared to other green energy solutions, and installation costs can be reduced if combined with other building work, and is therefore ideally fitted during construction of new developments.
Running costs will depend on the size of the building and how well insulated it is; ground source heating works especially well with under floor heating systems, and is most beneficial in buildings that are draught-proof and well insulated. Heat generated in excess to required consumption may be eligible for purchase through the government’s Renewable Heat Incentive, providing an income for the property owner. Combined with lower heating costs compared to other heating fuels, including electric, oil and solid fuel, these financial benefits could make the property more desirable to future purchasers.
Ground-source heating can be used in conjunction with other green energy sources, such as solar power, to produce an optimum combination for efficient, reliable and inexpensive renewable power.
For more information about how ground source heating can be used in new build developments or to see case studies of existing projects, visit the Geothermal International website.
Art: Geothermal International