River source heat pumps
An economical and efficient renewable energy solution — any large water source near your building is an ideal energy source for a heat pump.
How river source systems work
A river source heat pump abstracts water from a river, canal, estuary or other open water body, passes it through a heat pump to extract thermal energy, then returns the water — typically a few degrees cooler — to the same source.
The water source provides around three quarters of your heating and hot water needs, with the remaining energy supplied by electricity to run the heat pump. This dramatically reduces both your carbon footprint and heating bills.
This method can also be used with other flowing or large water sources including estuaries, lakes, seas and oceans. Although traditionally associated with rural or waterside locations, we're increasingly installing river source systems at urban sites — including canal-side developments in city centres.
Key specifications
- Water sources
- Rivers, canals, estuaries, lakes, seas
- System sizes
- 20kW to 1MW+ for large commercial
- Abstraction
- Pumped intake or submerged abstraction pods
- Discharge
- Returned to source (typically 2-4°C cooler)
- Licensing
- EA abstraction and discharge licences required
- Cooling
- Reversible systems provide summer cooling
End-to-end capability
River source projects require expertise in EA licensing, abstraction engineering and heat pump installation. Nicholls is one of very few companies that provides all three under one roof.
Why river source?
Highly efficient
Water holds thermal energy more effectively than ground. River source systems can achieve COPs of 4.0–5.0+, making them among the most efficient GSHP types.
No boreholes needed
Unlike closed-loop or open-loop systems, river source doesn't require drilling — the water body itself is the heat source, reducing installation complexity.
Heating and cooling
Reversible systems provide both heating in winter and cooling in summer from the same water source — reducing the need for separate HVAC equipment.
Scalable
Systems scale from medium residential (20kW) to large commercial developments (1MW+). Multiple heat pumps can draw from the same water source.
Lower carbon
Replaces gas or oil heating with ~75% renewable energy from the water source. The remaining 25% is electricity, which gets greener as the grid decarbonises.
Property value
Renewable heating systems add value to commercial and residential properties, particularly as energy performance requirements tighten.
Design and installation process
River source projects involve close coordination with the Environment Agency. Our combined licensing, engineering and installation expertise streamlines the process.
Feasibility assessment
We assess the water source — flow rates, seasonal temperature variation, water quality and proximity to your building.
EA engagement
Our licensing team initiates pre-application discussions with the Environment Agency for abstraction and discharge permits.
System design
Heat demand, abstraction volumes, intake design (pumps, frames or submerged pods) and plant room layout are all specified.
Licence application
Full EA licence application prepared and submitted, including environmental impact assessment and monitoring proposals.
Installation
Our engineers install the abstraction system, connecting pipework from source to plant room, heat pump equipment and full commissioning.
Compliance & maintenance
Ongoing support including EA licence compliance, monitoring, annual reporting and system maintenance.
River source heat pump — Norwich
A 435kW open-loop river source system providing renewable heating and hot water for 86 apartments on the River Wensum in Norwich, replacing gas heating entirely. This project involved close liaison with the EA for abstraction and discharge licensing.
435kW
System capacity
86
Apartments heated
~75%
Carbon reduction
River Wensum
Water source
Suitable for
River source systems suit any property near a substantial water source. Although traditionally associated with rural sites, we increasingly install at urban canal-side and riverside locations.
Near a river, canal or water source?
Contact us for a feasibility assessment — we'll evaluate the water source and handle all EA licensing.