Register an exemption for an open-loop ground source heating and cooling system
Check if you're exempt from needing an environmental permit for discharges from an open loop ground source heating and cooling system. Then register this exemption.
Applies to England
The guidance on open loop heat pump systems: apply to install one explains:
- what these systems are
- the environmental permissions you may need to operate these systems
You may be exempt from needing an environmental permit for discharges from your ground source heating and cooling system if it is any of the following:
- a cooled aquifer system with a volume of less than 1,500 cubic metres per day
- a balanced system with a volume of less than 430 cubic metres per day
- a heated aquifer system with a volume of less than 215 cubic metres per day
But you must:
- meet all of the conditions of this exemption
- register your exemption with the Environment Agency
- have the other permissions you need for the system, such as for investigating and abstracting a groundwater source
There’s separate guidance on environmental permissions for closed loop ground source heating and cooling systems.
Conditions of the exemption
The system must:
- abstract and discharge within the same aquifer
- discharge water at a temperature that will not go above 25°C and will not vary by more than 10°C compared to that in the aquifer from which it was abstracted
- not be on a known contaminated site or one where contaminating activities used to take place – contact your local council to find this out
The water within the system must not:
- have anything added to it – for example additives used for descaling
- be used for any other purpose
The system must not discharge water within any of the following areas.
Watercourse or a groundwater-fed wetland
The system must not discharge water within 50 metres of either:
- a watercourse
- a groundwater-fed wetland (for example, a Site of Special Scientific Interest)
You can check the locations of these using Magic map. Natural England also provides a list of designated sites.
Groundwater abstraction
The system must not discharge water within 50 metres of any groundwater abstraction (for example borehole, well or spring) used for any purpose.
To get information on:
- current groundwater abstraction licences, email enquiries@environment-agency.gov.uk and include the location of your system and the search radius of 50 metres
- private groundwater abstractions, contact your contact your local council’s environment health department
Groundwater source protection zone 1
The system must not discharge water within a groundwater source protection zone 1 (SPZ1) that’s used to supply water for domestic or food production purposes.
You can find groundwater SPZs on Magic map.
Before you fill in the exemption form
You will also need to check the following before you fill in the form.
Operator status
You need to be the operator of the open-loop system to register it. This usually means you are the owner of the property where the system is located.
Location details
You will need to give a grid reference for where the open-loop system is located. This may be different from the operator’s address.
Water temperature ratio
You will need to know the 5-yearly average discharge water to abstracted water temperature ratio for your system.
To calculate your 5-year ratio, divide the average discharge water temperature by the average abstracted water temperature.
Example calculation
Average temperature of water discharged = 13.5°C
Average temperature of water abstracted = 15.0°C
The temperature ratio in this case is 13.5 ÷ 15.0 = 0.9
If you do not have 5 years of data, base your calculations on your system’s constraints. You should monitor flow and temperature to stay within these constraints.
Register your exemption
You must register your exemption with the Environment Agency if you can meet all of the conditions.
You need to register each point of discharge separately.
It’s free to register.
If your details change
You must register a new exemption if you are the operator and your details change. Such as:
- a company title change
- passing on ownership of the system
You cannot transfer a registration to someone else.
Cancelling an exemption
Email psc-waterquality@environment-agency.gov.uk if you need to cancel an exemption registration.
If you cannot meet the exemption conditions
You will need to apply for a bespoke permit for the discharge instead. Check the guidance on open loop heat pump systems: apply to install one.
Get help
Email psc-waterquality@environment-agency.gov.uk for help with the registration form.