With continuously growing operation costs, and public pressure to reduce expenditures, Hampshire Fire and Rescue Service decided to install PV systems on top of 12 fire stations and three headquarter buildings across Hampshire. It initially specified for a standard string inverter, but Solar-Voltaics, a Hampshire based specialist in commercial solar installation recommended the SolarEdge solution for several reasons:
The design flexibility of the SolarEdge solution allows connection of strings over multiple roof facets and angles. Longer strings allowed Solar-Volatics to reduce the number of strings in the system by one third in comparison to a traditional string inverter. The built-in safety solution further reduced the installation cost. “For complex roof installations the inherent simplicity of string design and the need for fewer strings provides a welcome reduction in installation time,” said Solar-Voltaics’ Mike Turner.
Many fire stations have complex roofs and shading caused by training towers and communication antennas. With module-level optimisation, each module produces maximum power, independently of other modules in the string. This solution eliminates shading and other mismatch related power losses.
To enable maximum electricity bill savings, the two largest systems, on top of the headquarters building and fleet maintenance building, are utilising the SolarEdge export limitation feature which allows maximum self-consumption while complying with grid restrictions. “The enhanced performance that the system offers and the versatility available as standard, such as the ability to connect meters and provide export limitation make the solution hard to beat and certainly worth the cost compared to conventional string inverters,” Turner said, adding: “the 25 year warranty on the optimisers and 12 year warranty on inverters reflect the reliability we have experienced and provides a reassurance that PV systems installed with SolarEdge technology will continue to provide high performance levels for many years to come.”
Installing PV on fire stations poses safety concerns. With the SolarEdge solution, whenever the AC power or the inverter are turned off, its DC wires de-energise to a safe DC voltage during installation, maintenance and emergency. The Hampshire Fire and Rescue Service chose to equip all PV sites with the SolarEdge firefighter gateway which allows central safety management for the PV systems, including automatic and manual system DC shutdown, real time indication of system DC voltage for safety assurance and emergency stop button for the entire PV system.
“I believe the SolarEdge DC optimiser solution is the most advanced and reliable solution for the safe installation of solar PV. Our customers especially value the fire safety features and the remote monitoring capability, all of which help protect their assets and investment in solar energy,” Turner said.
- Project capacity: 700kW on 15 sites
- Location: Hampshire, UK
- Installation date: 2014