Scottish Water has started to install its first combined solar power and battery storage facility near Perth’s Waste Water Treatment Works at Sleepless Inch on the River Tay.
The £2 million ($2.6 million) project is the largest single solar energy investment announced to date by the publicly-owned water company’s commercial subsidiary, Scottish Water Horizons.
The renewable energy generated is expected to provide around a quarter of the electricity needed to treat water that has been used by customers all over the city, enabling it to be safely returned to the environment.
Some 2,520 solar panels will be installed on land adjoining the treatment works, with a combined generating capacity of just over 1MW.
It will be the first Scottish Water solar project to include battery storage, in the form of four vanadium flow batteries (VFBs), capable of storing up to 0.8MWh of energy.
The project is being developed and constructed by Scottish renewable energy solutions specialists, Absolute Solar and Wind, with the batteries supplied by Invinity Energy Systems.
The system is expected to be operational in 2021.
The inclusion of battery storage will enable around 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.
By using this solar power on-site instead of exporting to the local grid, the treatment works will cut its carbon footprint by around 160 tonnes of CO2 per annum – the equivalent of offsetting 580,000 miles from the average passenger car. It will also help to reduce energy costs at the site by approximately 40% on an ongoing basis.
In addition to the new photovoltaic panels and batteries, Scottish Water Horizons’ project will also include the installation of electric vehicle charging facilities to support the transition of the company’s 1,600-vehicle fleet of vans and tankers away from fossil fuels towards clean electricity.
Donald MacBrayne, business development manager at Scottish Water Horizons, said: “This project represents an exciting step forward in our work towards Scottish Water’s ambitious goal of achieving net-zero carbon emissions by 2040.
“Perth is right at the heart of Scotland and has its own emerging ambition to become the most sustainable small city in Europe. We hope this project and Scottish Water’s continuing journey towards net zero can support that goal.”
Environment and climate change secretary Roseanna Cunningham MSP, adds: “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.”
Scottish Water Horizons has already delivered 46 solar power projects, as well as 20 wind projects, two biomass projects and a wastewater heat recovery project.