What is Geothermal energy?

Geothermal energy is energy stored beneath the earth’s surface in the form of heat. It can be used to heat homes, office buildings and to generate electricity.

Benefits of geothermal energy:

• Carbon free
• Renewable
• Sustainable,
• Uninterrupted energy source
• Local resource
• Stable cost, no fluctuation as with gas or oil
• Low maintenance costs
• Energy security
• Little footprint at ground level

It’s not new, geothermal has been around for as long as people have been able to take advantage of it. Humans have been using geothermal energy in the form of hot springs and steam geysers for bathing and agriculture for hundreds of years.

Geothermal is set to become a popular option in the renewable energy mix. The Scottish Government has “identified deep geothermal energy as an important emerging renewable energy technology that could have the potential to play a significant role in Scotland’s future energy provision”.

The following videos are excellent explanations of geothermal possibilities.

• The Eden Project
• Geothermal District Heating
• TownRock Energy

Geothermal Energy in Scotland

The Geothermal Energy Challenge Fund supported 4 feasibility studies to explore the potential of geothermal resource sites in Fife, North Lanarkshire, Aberdeen City and Aberdeenshire. The completed Geothermal Energy Challenge Fund feasibility studies have now been published and can be found in the links below:

• Aberdeen Exhibition and Conference Centre
• Fortissat, North Lanarkshire
• Guardbridge, Fife
• Hill of Banchory, Aberdeenshire

Ground source heat pumps (GSHPs) use pipes that are buried underground to extract heat from the ground, which is then used to heat radiators, underfloor or warm air heating systems and hot water. A ground source heat pump circulates a mixture of water and antifreeze around a loop of pipe, called a ground loop, which is buried underground. Heat from the ground is absorbed into the fluid. The fluid then passes through a compressor that raises it to a higher temperature, which can then be used to heat water for heating and hot water circuits. As the ground stays at a fairly constant temperature under the surface, the heat pump can be used throughout the year. The Ground Source Heat Pump Association (GSHPA) has some useful information and interesting case studies.

Water Source Heat Pumps work in a similar way but with the loops of pipe immersed in water rather than buried in the ground.