Ground Source Geothermal Borehole Systems

At Drilcorp we have turned our decades of experience in borehole drilling to the emerging field of groundsource geothermal boreholes. Our extensive knowledge of drilling and geotechnical exploration has seen us work on a growing number of projects – across both open-loop and closed-loop groundsource schemes.

Find out more about our groundsource services

Why is heat extraction important?

Over recent years there has been a sustained drive to reduce human influence on global warming and seek out environmentally friendly ways to approach energy generation and temperature regulation. 

There have been great strides made in the way we heat and cool buildings using heat pumps to collect low-grade heat from a sustainable source, pass it through a compressor and multiply it to become useful for heating water or space within a building. If reversed, the heat pump can also be used for cooling. 

Sustainable sources include the atmosphere (airsource), the Earth (groundsource) and now disused flooded mine workings (minesource).

Open-loop Groundsource

An open-loop system generally uses boreholes to provide groundwater to feed the Heat Pump, which will air condition (either warm up or cool) a space. Many of the large open loop projects Drilcorp has been involved with such as the Royal Festival Hall have been designed for cooling purposes. In basic terms, open loop boreholes are really water supply boreholes which need to be drilled and developed to exacting standards for optimum performance. 

An open loop system consists of an ‘Abstraction Borehole’ fitted with a submersible pump to deliver water to the Heat Exchanger. Here heat is transferred from the groundwater to warm the premises or alternatively heat is transferred from the premises to the groundwater. 

The ‘heat altered’ groundwater now continues its journey to a second ‘Recharge Borehole’. The system is designed so that the Recharge Borehole is down flow of the abstraction borehole or ideally the recharge water is taken to a different aquifer to avoid short circuiting. 

Drilcorp’s expertise in constructing, developing, installing, and commissioning large commercial water supply boreholes gives our clients the confidence they need to commission our services for their Open Loop Systems.

Ready to get started on an open-loop groundsource project?

Closed-loop Groundsource

A closed-loop geothermal borehole system uses boreholes as a source for heat transfer from the ground into a premises. The size of the space to be heated determines the quantity of boreholes needed. A closed loop system for a single house may be just one borehole drilled to a depth of 100 metres, whereas a closed loop system for a large premises such as a school or hospital may need a grid of hundreds of boreholes drilled to around 200 metres. 

Each borehole is fitted with a loop comprised of two plastic tubes running the full depth of the borehole with a ‘u’ bend at the base. Pipework is run through trenches from the borehole to the Heat Exchanger (via a manifold where multiple boreholes are concerned). 

The loop system is filled with a liquid refrigerant and the heat pump circulates this refrigerant down the borehole, where it picks up heat that can be transferred to the premises space. 

At Drilcorp our low ground pressure rotarytop drive track-mounted drilling rigs are ideal for drilling boreholes for closed loop groundsource boreholes. 

Ready to get started on a closed-loop groundsource project?

Our Clients

Drilcorp work with a number of prestigious clients from Local Authorities, Food and Drink Manufacturers, Consultants and Contractors and Water Utility Companies.

Get in touch

Ready to find out more about how Drilcorp
can help you on your next project?