Our most-entered category, commercial rooftops present the perfect marriage between installation footprint, energy demand and solar production.

Entries from some of the UK’s most recognised brands have dominated the shortlist, with supermarkets starting to recognise their solar potential.

Great Yorkshire Showground, Duncan Renewables

Duncan Renewables’ 245kW PV rooftop at the Yorkshire Showground is an events space run by the Yorkshire Agricultural Society. Producing 203,473kWh per year, the rooftop is part of the Agricultural Society’s aim to reduce its carbon footprint.

The site had to be built swiftly due to the frequency of the building’s use for events and was planned with local authority for minimal disruption. The site is within the Harrogate Conservation Area and is highly visible from many popular walking routes, but support from Harrogate Borough Council helped set a precedent, raising support from local authorities for renewables development.

Greggs 10 Site Solar PV Installations, Solar Advanced Systems

After winning a competitive bids process, Solar Advanced Systems has installed 10 systems for Greggs the Baker. The commercial rooftops were installed on Greggs’ manufacturing sites across the UK with only eight months from contact to installation. Solar Advanced Systems said it won the contract despite the competitive bids because of the 0% finance capital outlay plan proposed.

Solar Advanced Systems individually designed the systems, meeting Greggs’ challenging health and safety requirements. Six of the rooftops were installed with 50kWp systems between May and July, and four sites with 250kW from August to September. The installations will help Greggs to reach its sustainability targets.

Morrison's Bridgwater RDC, GMI Energy

GMI Energy installed 4MW of PV rooftop for Morrison's supermarkets' new store buildings, including 1MW at a regional distribution centre in Bridgewater.

Generating 8.69MWh a year using 235W polycrystalline Canadian Solar panels and Power One inverters, the system has a lifespan of 25 years, saving approximately 456 tonnes of carbon emissions a year and producing enough electricity to power 263 homes.

The installations are part of Morrison's targets to reduce its carbon footprint by 30% by 2020. The installations faced challenges such as meeting FiT deadlines, strict health and safety regulations, reducing construction disruption as well as planning approval and a one-day window for grid connection.

Sainsbury's Installation, Renewable Resources (Energy Solutions) Ltd

Sainsbury’s ambitious corporate environmental target aims to reduce its operational carbon emissions by 30% absolute and 65% relative by 2020. In order to realise this, the supermarket giant has engaged in a mass rollout of solar across its stores.

Renewable Resources has installed a total of 209 arrays over 183 stores, representing over 21MW of installed capacity. The solar rollout is expected to reduce Sainsbury’s annual carbon footprint by more than 7,500 tonnes as well as significantly lower energy expenditure.

Tesco Hawk, Photon Energy

Designed and installed by Photon in December 2011, the 250kWp system for Tesco generates 230MWh a year and is made up of 1,036 LDK 240Wp polycrystalline modules, arranged in 19 sub arrays of 56 rows and two modules each. One Fronius CL60, and three CL48 inverters were used – central inverters instead of string were used as well as modified S-Level mounting systems from German suppliers, K2 Systems. This was due to the lightweight construction of the roof. The rooftop is part of Tesco’s renewable requirements, saving 120 tonnes of carbon a year.

Natural Sparx, powered by Rexel Energy Solutions, sponsors of the Commercial rooftop installation category will be exhibiting at stand D22 at Solar Energy UK. Listen to Jerry Hamilton, the company’s director of renewables preview the shows presence at Solar Energy UK on the latest Solar Media Editors’ podcast here.