Environment Agency position on GSHC

This page summarises the full Environment Agency Position statement on GSHC:

We support the development of sustainable renewable energy whilst ensuring that appropriate measures are in place to protect the environment. Ground source heating and cooling (GSHC) systems can help to meet UK Government renewable energy and greenhouse gas reduction targets.

We encourage GSHC systems that are well-managed and designed to present a low risk to the environment and other users of water. Open loop systems require three permissions from us. Closed loop systems do not need a permit from us but clear guidance should be followed to minimise the risks of groundwater pollution.

We have published an Environmental Agency GSHC Guide which states how to comply with environmental legislation and achieve good practice.

Background and Context

Achieving UK climate change targets will require a massive shift from fossil fuels to renewable energy and other technologies with low greenhouse gas emissions. The UK is committed to generating 15% of its energy from renewables by 2020. This includes heat, of which only about 1% currently comes from renewable sources. Government projections suggest that this should increase to 12% by 2020, which is an enormous challenge.

Environmental Risks of GSHC Systems

Whilst we support the use of GSHC systems, there are associated environmental risks. Systems that are well designed, managed and follow our Guide present a low risk to the environment.

Deep open loop and closed loop systems installed can result in the interconnection of different aquifers affecting water quality and flow. These risks occur during drilling, installation and decommissioning. All GSHC systems can also result in undesirable temperature changes in the water environment with impacts on water quality or aquatic ecology. These risks can be managed by following our Guide.

Where cooling, such as air conditioning, is already required in a building (or is part of a new building design) we encourage the development of balanced heating and cooling systems as these result in lower net cooling or heating of the ground or groundwater over time.

There are additional concerns for open loop systems. Where they discharge into the aquifer there may be adverse impacts, such as localised increases in groundwater levels which could impact on adjacent structures. The main additional environmental risk associated with closed loop systems is the potential to pollute groundwater if circulation fluid leaks.

Our Role on Open loop systems

We regulate open loop systems. They require a Groundwater Investigation Consent followed by an abstraction licence and an environmental permit to discharge water. Where necessary, to protect the environment, we will set temperature limits on the environmental permit to discharge. These permits and consents allow us to ensure that systems comply with environmental legislation and avoid undesirable environmental impacts.

We have a presumption against consumptive open loop systems where discharge is to a different source of supply (including different geological strata) because water is effectively lost from one source of supply. In effect, they use the water resource, reducing its availability to other users and the environment. In practice, applicants may be unable to obtain an abstraction licence where water resources are heavily used, and if they do obtain a licence, the charge may be higher than for non-consumptive systems. Non-consumptive systems will also have localised impacts and these will be assessed during determination of the abstraction licence.

Developers of open loop GSHC systems should contact us at an early stage to discuss the intended location, proposed design, and operation of their system. Early dialogue will help ensure a faster permit determination and reduce the need for any system redesign.

Closed loop systems

Closed loop GSHC systems do not require a permit from us because under normal operation they do not introduce pollutants into the aquifer. However, we strongly recommend that these systems use non-hazardous substances to avoid pollution of groundwater in the event of a leak. If leaks occur and pollutants may enter groundwater we can serve notices to prohibit the discharge or require a permit.

Role of the installer and operator

Operators of GSHC systems must adhere to environmental regulations and any conditions we attach to permits. They should also follow our Guide.

The efficiency and longevity of a system are the responsibility of the designer, installer and operator who must consider issues such as whether the operation of a system would make the local ground or groundwater warm or cool to a point where the system no longer runs efficiently. These issues do not specifically fall within our remit as a regulator. Developers of open loop systems should contact the Environment Agency at an early stage to discuss their proposals.

This page summarises the full Environment Agency Position statement on GSHC