Solar panel system installed at DPD's HQ

The array is made up of 3,636 panels and extends over 5,284 sq metres on the roof of the parcel distribution hub in Broadwell Road.

The move is part of DPD's commitment to become carbon neutral and it is estimated the array will save 408 tonnes of CO2 a year.

Work on the project was completed last month as part of the firm's Driving Change corporate social responsibility (CSR) strategy which involves every parcel it delivers being 'carbon neutral', for all of its customers, at no extra cost to them.

Commercial solar PV developer and installer EvoEnergy designed and fitted the 999.9 kWp system, which is now mounted on the roof.

The array will generate approximately 860 MWh of clean electricity every year, with 85 per cent of the generation expected to be used onsite.

Peter Alder, head of sales and marketing at Nottinghamshire-based EvoEnergy, said: "Due to our experience in similar projects, we were pleased to be able to work with a client that possesses an outstanding reputation for innovation and technology adoption.

"The end result is a high quality building integrated system that will be a valuable asset to the company for many years to come."

The system was fitted to the site's large trapezoidal roof over an eight week period in November and December 2016 with a ten-man team using a single point of access to the building roof to minimise disruption to DPD's day-to-day operations.

The site is subject to a 500 kWp export limit by the regional Distribution Network Operator (DNO); a ruling which could have reduced the size of the finished array by half.

However, by fitting a unique high voltage sensing Export Power Control (XPC) system on site to constrain the amount of power that ever gets exported, EvoEnergy made sure DPD got the full-size array wanted; maximising energy and carbon savings.

Mark Wilkes, director of technical services at DPD, added: "The service provided by EvoEnergy has been excellent throughout this project. Their project delivery programme was well thought out and integrated seamlessly with our own operation and was delivered on time with professionalism and attention to detail.

"It is important for us to partner with like-minded businesses and for them to be able to work alongside us delivering on the needs and vision of DPD."

The system will reduce the company's carbon footprint by more than 400 tonnes a year, whilst also providing them with an income from the feed-in tariff for 20 years and significant savings on their energy bills.

The system is designed with the latest commercial SolarEdge technology that not only optimises the generation, but also provides arc fault protection to prevent fires by automatically reducing the voltage to a safe level should any faults be detected.

DPD employs around 1,500 people at its 27-acre headquarters site in Broadwell Road,

DPD is a member of one of Europe's leading parcels groups, wholly owned by France's La Poste, the second largest postal group in Europe. It also operates the Interlink Express site at Roebuck Lane in Smethwick, which employs around 500 people.

The company employs more than 9,000 people in the UK, operating more than 3,000 vehicles from 56 locations and delivers 200 million parcels a year.