Clean power at Farmoor Reservoir
We're on a mission to reduce emissions associated with treating and distributing water. As part of this, we’re planning to install a floating solar array at Farmoor Reservoir. This will help to power the water treatment works.
The solar array will be located within the north section of the reservoir known as Farmoor 1. It will produce enough renewable electricity to power around a quarter of the site’s needs.
We’re working to find a partner who will design, build and operate the project on our behalf. We hope to be in a position to start building in autumn 2026. Construction is expected to last around 16 weeks.
An artist's impression of how the solar array could look
A birds eye view from above the sailing club
View from the Cumnor Road
About the project
Farmoor Reservoir provides a critical store for raw water. The on-site water treatment facility processes around 100 million litres of water every day. This is then released for use by local homes and businesses.
The project will help to:
- Save up to 900 tonnes of carbon dioxide equivalent every year by producing our own electricity. This is equal to taking over 600 cars off the road
- Lock in a cheaper long-term price for electricity
- Protect customers against future price rises and wholesale energy markets
The final design will depend on which partner we choose to work with. However, our expectation is that the solar array will take up less than 10% of Farmoor 1.
Benefits of floating solar power
We already use rooftop solar at some of our sites. We don't have enough space to put solar panels on buildings at Farmoor water treatment works. It also wouldn't make a meaningful contribution to the power demand.
Floating solar does not compete with other key land uses. Instead, it takes up a small area of the reservoir surface. They also tend to generate more electricity than ground-mount and rooftop systems. This is due to the cooling effect of the water.
Similar projects have shown that floating solar projects can improve water quality. This is due to shading, which can reduce evaporation and algal blooms.
Disruption to visitors and wildlife
We recognise that Farmoor Reservoir has an active community. This includes bird-watchers, anglers, and water sports enthusiasts.
It has thousands of visitors a year, and we see no reason why that shouldn't continue. For safety reasons, there may be some temporary restrictions on site access. It may impact on and around the reservoir during construction. We expect the impacts to be minimal.
We are also working with a variety of experts to get a better understanding of the resident birds and fish. This will help to inform the final design of the project, which aims to keep any impacts to wildlife to a minimum.
Contact and further information
If you have any questions about the project, please email renewables@thameswater.co.uk.