Polysolar designed, supplied, installed and commissioned a rooftop solar PV system for Network Rail at the new Beaulieu Park Station in Chelmsford. The array powers the station's own electrical loads first, so the station buys less electricity from the grid.

About the Project

Beaulieu Park is a new railway station on Generals Lane, Boreham, on the edge of Chelmsford in Essex. Network Rail is the client, and J. Murphy & Sons (Murphy) was the principal contractor. We worked for Murphy as the specialist solar PV subcontractor.

The system sits on the standing seam metal roof of the main station building. It has twenty solar panels with a combined capacity of 8.7 kWp (kilowatt-peak, the system's maximum rated output). The panels feed a single inverter in the electrical room on Platform 3.

The Challenge

The station was an operational railway environment, so we could only work within restricted hours. All work also had to meet RISQS (Railway Industry Supplier Qualification Scheme) requirements for non-trackside activities. This kept the works safe and caused as little disruption as possible to the station.

The project also involved several contractors. The electrical specification. These included a separate relay to isolate the solar system automatically, DC cable trays and risers, specialist DNO (Distribution Network Operator) meters, and the main incomer and AC isolation switches. We had to coordinate with each of these packages so the finished system worked as one.

Rail-industry quality controls governed every stage. Murphy's inspection and test plans set hold points for drawing approval, method statements and health and safety documents before work could start on site.

The Solution

The twenty solar panels sit on aluminium mounting rails, clamped to the standing seam roof. We set the panels on a low 3–5 degree pitch facing south. This keeps them out of sight from ground level, so the array has very little visual impact on the new building while still performing well. Special panels were chosen to ensure rainwater didn't gather in the frames due to the low pitch.

We wired the panels as two strings of ten. Both strings run down to the electrical room on Platform 3, where we fitted a Solis 8 kW three-phase inverter. As the specification required, we chose an inverter with a built-in grid protection relay. We also supplied a generation meter with remote access, so the station can track how much electricity the system produces.

We made all the DC connections and connected the system to the switch room incomer. We set the system up so that everything downstream of the export meter benefits from it. The station's own loads, including lighting, use the solar power first. Any surplus goes back to the grid, and the station draws from the grid at night.

The Result

Our MCS-certified installation partner, Ablaze Green Energy Solutions, tested and commissioned the system. It passed all 12 test and commissioning checks to BS 7671.

We expect the system to generate about 6,773 kWh of electricity a year. The station uses that power first, which reduces its grid demand from day one. And because the panels can't be seen from ground level, the station gets clean energy without any change to how it looks.

Technical Specification

• System size 8.7 kWp


• Panel count 20 panels


• Panel dimensions 1812 x 1096 mm


• Array layout 2 strings of 10 panels


• Mounting Aluminium rails on standing seam metal roof, 3–5 degree south-facing pitch


• Inverter Solis S5-GR3P8K (8 kW, three-phase)


• Estimated annual generation 6,773 kWh

Project Details

• Sector Rail and transport infrastructure


• Client Network Rail

Installation Partners

• Principal Contractor J. Murphy & Sons

Planning solar for a station, depot or other operational site? Get in touch to discuss your project: 01223 911534