Case Study: Decarbonising Water Treatment with
Scottish Water

Invinity has delivered a 0.8 MWh flow battery system to Scottish Water in a solar and storage first which will help the company towards its net zero targets. Find out more in the case study below.

Flagship solar and storage scheme combines the company’s largest single solar energy array installed to date with an innovative Vanadium Flow Battery.

This latest investment by Scottish Water Horizons, the commercial subsidiary of the public water utility, will reduce emissions and directly contribute to meeting ambitious carbon reduction goals. It will also significantly reduce energy costs for the site, a saving that can ultimately be passed onto Scottish Water customers.

The Brief

Scottish Water have a target to host or self-generate three times their annual electricity consumption by 2030 and reach net zero carbon emissions by 2040. To achieve these ambitious targets, the company is installing solar panels across its sites as well as bringing in energy storage technology to maximise the use of this low carbon renewable energy source.

Invinity was chosen owing to our batteries’ strong credentials in terms of safety, durability and sustainability. Flow battery technology is an excellent fit alongside solar generation owing to the fact that it can perform many cycles per day enabling maximum onsite use of self-generated solar power.

The Result

Working closely with Scottish Water, framework contractor Absolute Solar & Wind and energy optimiser Open Energi, Invinity successfully delivered, installed and energised four VS3 Vanadium Flow Batteries, capable of storing up to 0.8 MWh of energy alongside a 1 MWp solar array. The inclusion of battery storage enables up to 94% of the renewable power generated to be used on site, with the flow batteries charging from renewable electricity produced when the sun is at its peak and then delivering it to the site when it is most needed, any time of the day or night.

“Innovative projects like this not only help us reach our goal of zero emission by 2045 but also help to support the Scottish manufacturing industry, the creation of green jobs and a green recovery from COVID-19.”

Commenting further on the announcement, Tom Newell, Managing Director at Absolute Solar and Wind, one of Scotland’s leading renewable energy project developers, said:

We are delighted to have been chosen as the Principal Contractor for the renewable energy scheme at Perth Waste Water Treatment Works. This will be Absolute’s 19th project constructed for Scottish Water Horizons and the first to feature a combination of solar PV, vanadium flow batteries and electric vehicle chargers. We look forward to working with both Scottish Water Horizons and Invinity Energy Systems during the delivery phase.”

– Tom Newell, Managing Director, Absolute Solar and Wind

Scottish Water Horizons has already delivered 46 solar power projects, as well as 20 wind projects, two biomass projects and a waste water heat recovery project. Scottish Water also hosts significant additional renewable generation capacity on land that it owns across Scotland.

Perth’s waste water treatment works at Sleepless Inch is a key site for Scottish Water, serving customers across the city. By installing energy storage, we can go even further in our use of self-generated renewable power, while also supporting the operation of the wider electricity system.– Donald MacBrayne, Business Development Manager, Scottish Water Horizons


Utilization of onsite PV generation


Reduction in electricity costs


Carbon Dioxide avoided each year


Ground mounted Solar PV


Vanadium Redox Flow Battery System

Project Partners

Click the links below to learn more about who we are working with on the Energy Superhub Oxford Project

University of Oxford
Oxford City Council
Habitat Energy