We were approached by a farm-based steel frame building manufacturer facing significant challenges with their off-grid power supply. The site had no connection to the electrical grid, relying instead on a 60kW three-phase generator to power its manufacturing operations. This generator was in use for up to 70 hours per week, often running at low loads to provide consistent power, particularly for lighting. The high fuel consumption, combined with frequent maintenance, led to substantial annual operating costs of approximately £33,500. Additionally, the generator’s continuous noise and environmental impact were concerns that the customer sought to address. Tasked with finding a more efficient, cost-effective, and quieter power solution, we set out to design and implement an off-grid solar power system tailored to the site’s needs.
Solution
Understanding the customer’s operational demands and the constraints of their off-grid location, we developed a comprehensive solar power solution. We installed 75 high-efficiency 450W solar panels on the site, taking advantage of the ample space available on the farm buildings. These panels were connected to five Victron MPPT charge controllers, which optimise the energy harvest from the solar panels, and a 6.15kW Victron Quattro inverter/charger system.
To ensure a reliable power supply, especially for the site’s three-phase equipment, we implemented a system that linked three of the Quattro inverters to provide a robust 90kW supply. However, for optimal performance and trouble-free operation, we designed the system to handle a maximum load of 60kW.
A key component of the solution was the integration of 60kWh of BYD battery storage. This storage system allows excess solar energy to be stored and used during periods of low sunlight, significantly reducing the reliance on the generator. The generator now serves as a backup, primarily needed during the winter months. From April to October, the site benefits from almost entirely free and silent solar power. During the remaining months, the generator operates for only about 10 hours per week.
Results
The implementation of our off-grid solar power solution has transformed the energy landscape for the customer. Over the nearly three years since installation, the system has performed flawlessly, providing a reliable, quiet, and cost-effective power supply. The generator, now relegated to a backup role, has seen its operational hours drastically reduced, with annual running hours cut to approximately 200, leading to significant savings in fuel costs.
The financial impact has been substantial. The annual operating costs have dropped from £33,500 to just £3,678.57, resulting in an annual savings of £29,821. With an estimated installation cost of £80,000, the return on investment (ROI) for the system is an impressive 2.68 years.
The customer was extremely satisfied with the solution, enjoying silent, sustainable power for most of the year, reduced environmental impact, and a significant reduction in operating costs. This case study highlights how our tailored off-grid solar solutions can deliver both economic and environmental benefits, ensuring reliable power even in remote, grid-independent locations.