The rooftop PV has been operational since 2015. Image: ROOF.

Atrato Onsite Energy (ROOF) has invested £6.6 million into a rooftop solar PV system situated atop what it said is a major Marks & Spencer (M&S) warehouse.

At the time of its installation in 2015, the 6MW system was the largest rooftop solar system in the UK, the company said.

The system consists of over 24,000 panels and was designed to make the fully automated distribution centre in Leicestershire close to self-sufficient during daylight hours.

Francisca Wiggins, director of renewable energy at Atrato Group, said: “Soaring electricity prices have made the business case for rooftop solar energy very compelling, Atrato Onsite Energy can provide corporations with long term, fixed price, green electricity at a substantial saving to current grid prices.”

Indeed, NatWest’s Sustainable Business Tracker recently found that 10% of SMEs are intending to invest in onsite generation by 2023, while earlier this year Solar Energy UK launched a Corporate Buyers’ Guide as interest in commercial solar continues to grow as a result of the high power prices over the last year.

ROOF, meanwhile, invests in and installs behind-the-meter solar energy generation systems, with these predominantly located on the roofs of commercial buildings. These are commercialised through long-term power purchase agreements. 

In November 2021, it raised £150 million through an oversubscribed IPO.