GROUND SOURCE HEAT PUMPicon-128px-ground-source

WHAT IS GROUND SOURCE ENERGY?

A heat pump is an electrical device that extracts heat from one place and transfers it to another. The heat pump is not a new technology; it has been used around the world for decades. Refrigerators and air conditioners are both common examples of heat pumps.

Ground source heat pumps (GSHP) are an environmentally friendly way of heating and cooling a building, delivering air conditioning and heating on demand all year round. This type of renewable energy technology can be installed into new builds or retrofitted into older buildings.

Businesses looking for a more energy efficient way of addressing their commercial heating solutions with renewable energy technologies would do well to consider ground source heat pumps, particularly if you currently use an electric, oil or LPG boiler for heating and hot water.

They are more energy efficient than air source heat pumps, but you will need a fair bit of outside space to install this type of renewable heating because pipework (ground loop) will need be to be buried in trenches or inserted into boreholes. Boreholes require less land but are more expensive, and access will be required for drilling. The length of the ground loop will be determined by the amount of heat required and the size of the building.

Ground source heat pumps will deliver lower fuel bills, and are particularly cost effective when replacing a conventional electric heating system. They are best suited to warm air heating and underfloor heating in terms of performance, although they can be installed to work with radiator-based heating systems. However, the heat generated is not as high as that of a conventional boiler.

Depending on the type of fuel they replace, ground source heat pumps produce lower carbon dioxide, reducing your carbon footprint. The impact is most noticeable when replacing coal or electric heating. Heat pumps, including ground source heat pumps, require electricity to run and are not entirely carbon neutral.

The technology is eligible for the government’s Renewable Heat Incentive (RHI) domestic and non-domestic scheme; a payment scheme designed to encourage individuals, businesses and organisations to adopt renewable types of heating.

HOW IT WORKS

Heat pumps transfer heat by circulating a refrigerant substance through a cycle of alternating evaporation and condensation (see diagram to the right). A compressor pumps the refrigerant between two heat exchangers. In one heat exchanger (the evaporator), the refrigerant is evaporated at low pressure and absorbs heat from its surroundings. The refrigerant is then compressed en route to the heat exchanger (the condenser), where it condenses at high pressure. At this point, it releases the heat it absorbed earlier in the cycle. 

With a ground source heat pump, pipes are buried in the ground to extract heat energy which is used to provide hot water and heat for radiators, warm air heating systems or underfloor heating. The mixture of refrigerant and water is circulated around a ground loop (the pipework) by the heat pump. Once the heat energy from the ground is absorbed into the fluid, it passes through a heat exchanger and into the heat pump.

The ground loop is either laid flat, coiled in trenches in the ground or installed vertically if space is an issue. Although heat pumps need electricity to run, they are far more efficient and environmentally friendly than conventional boilers.

The heat that is taken from the ground comes from the sun’s rays and as long as the sun shines, the ground is recharged during the summer months. Ground source heat pumps work efficiently throughout the year and can meet your heating, hot water and cooling needs all year round. 

Their efficiency is measured by their co-efficient of performance (COP), which is the ratio of the heat delivered to the electrical energy consumed to generate it. If the ratio is higher, the unit is more efficient. The COP of ground source heat pumps varies depending on the installation but is expected to be around 4.5, which means that, for every kWh of electricity it consumes to run, it will produce the equivalent of 4.5kWh of heat, reducing your heating energy consumption considerably.

Diagram that shows how ground source heat pumps work

WE DELIVER

Environmental Energies supply and install the NIBE range of ground source heat pumps, which range from 5kW to 60kW, with the 60kW pump capable of producing up to 540kW of energy and being the most user friendly commercial heat pump available. Eligible for the Renewable Heat Incentive (RHI) scheme, these heat pumps come with up to 8 climate system options, including passive and active cooling. Ground source heat pumps are perfect for buildings with a high heat demand. 

NIBE is a Swedish company offering world class solutions in sustainable energy and are a market leader in the industry.

We provide a turnkey solution, including design, supply and installation, along with the option of an ongoing maintenance programme if required. We will help you apply for the government’s Renewable Heat Incentive (RHI) and provide you with calculations on both your financial and carbon emission savings.

Ground source heat pumps are capable of supplying 100% of your heating and cooling needs throughout the year and are exceptionally cost effective.

icon-64px-case-studiesGROUND SOURCE HEAT PUMP CASE STUDY

Discover how we’ve used ground source heat pumps to reduce costs, carbon footprint and taxes.

Case studies coming soon, please contact us for examples of our work.