Scottish Water PV solar solution at Bathgate Wastewater Works

Project summary

Absolute Solar and Wind, on behalf of Scottish Water Horizons, has completed a £675,000 photovoltaic (PV) solar project at its wastewater treatment works in Bathgate, West Lothian. The completion of this project forms part of Scottish Water’s renewable energy drive to achieve net zero emissions by 2040.

The background

Absolute Solar and Wind was awarded the Bathgate project through Scottish Water’s Renewable Energy Framework. As an approved EPC contractor, Absolute has collaborated with Scottish Water Enterprise for several years, successfully delivering projects across multiple locations. Bathgate is the latest site to be energised, with additional projects set to be undertaken across Scottish Water’s estate in 2025.

Absolute collaborated with Scottish Water Enterprise’s operational and project management teams to identify suitable sites, conduct pre-design surveys and studies and develop tailored solar PV solutions. These solutions aim to reduce each site’s carbon footprint while supporting Scottish Water’s goal to achieve net zero emissions by 2040. Absolute managed all aspects of design, scope, supply and installation, working closely with local Scottish Water project teams and their subsidiaries to deliver an optimal renewable energy solution.

The challenges

The land at the Bathgate site was unsuitable for ground-mounted solar installations because it was largely unused and overgrown. This required an innovative solution to deliver solar power to the site, a challenge that was compounded by limited access within the site’s boundary. To ensure the wastewater treatment works remained operational throughout the duration of the work, the treatment works remained live, requiring the Absolute team to navigate a live operational site. Also, because of the age of the motor control centre (MCC) on-site (the point of grid connection), the system did not have the capacity to incorporate the solar PV installation, and an electrical infrastructure solution was needed to enable the solar PV installation to connect.

The solutions

Given that the site was a live operational facility for Scottish Water, Absolute worked closely with the local operations team to coordinate the MCC shutdown – both for the initial survey and later for the connection. In the case of Bathgate, a bespoke solution was needed to enable the solar PV connection owing to the current system having inefficient capacity. This process was carefully planned and executed to ensure minimal disruption. During the design phase, Absolute meticulously scheduled multiple contractors, including the Distribution Network Operator, to streamline the shutdown process and further reduce operational impact.

Proper land preparation during the pre-construction phase was crucial owing to the highly corrosive nature of the soil, which necessitated a specialist mounting kit. A ballasted system was chosen as the most suitable solution, but its implementation required extensive ground preparation by specialist contractors. The Bathgate site had limited access and egress, requiring careful planning for module placement. The layout was strategically designed to facilitate construction while ensuring the site remained fully functional and operational.

During the electrical survey, it was determined that the existing MCC lacked the necessary capacity, requiring a bespoke extension design. Absolute successfully collaborated with the original MCC manufacturer, BGEN, to develop a tailored MCC solution that seamlessly integrated with the capacity requirements of the PV solar system designed for this unique location.

The impact

Absolute Solar and Wind’s work on this project has played a crucial role by ensuring efficient design, seamless execution and minimal operational disruption. Through careful planning, collaboration with key stakeholders and the use of innovative solutions, a high-quality renewable energy system tailored to the site’s specific needs has been delivered.

This project not only contributes to reducing carbon emissions in line with Scottish Water’s net zero target in 2040 but also enables Absolute Solar and Wind to continue to be a valued partner of Scottish Water in the development of future PV solar solutions across its estate.

By overcoming site-specific challenges and implementing best practices, Absolute Solar and Wind is helping to drive innovation in renewable energy solutions for Scottish Water, further demonstrating that it is a key partner supporting the achievement of renewable energy goals. Beyond the technical benefits, the project will have a lasting positive impact on the community by contributing to a cleaner, more sustainable environment.