20 Fenchurch Street

Home >> Case Studies >> 20 Fenchurch Street

One of the UK’s highest solar panel installations has just been completed by EvoEnergy on top of London’s 38-storey ‘Walkie Talkie’ skyscraper at 20 Fenchurch Street.

The 250-panel, 50 kWp PV system was fitted to the roof of the building between July and September. Now finished, it’s in the top 10 list of highest solar arrays in the country.

Due to the unique nature of the project – installing a completely rail-less system on a glass roof 160 metres above street level and three floors above the inverter – and it’s location in the heart of the City of London, a series of bespoke engineering and logistical solutions were required.

Because of space restrictions, materials could only be moved on to the site as they were needed, with one delivery being made as one was being used. Constant coordination with crane and delivery teams was required just to get the materials up to the roof, where the EvoEnergy team had to work around dozens of other contractors to fit the panels gradually, row by row, as the glass roof was put into place.

A specially trained four-man team carried out every part of the project, working high up in extreme and often windy conditions. Rope access techniques were required just to get to the working area because of the slope of the glass, while everyone and everything had to remain tethered to the building at all time – including every panel, every tool, every nut, bolt and screw.

Furthermore, the team wore specially designed rubber shoes in order to avoid scratching the glass roof but these made working challenging in wet weather conditions.

All of this inevitably meant that the installation team sometimes needed to pause for a number of weeks at a time while other parts of the construction process were completed. However on the most productive days the team could complete a whole row of 22 rail-less panels in a day.

Each 200W panel was fixed to the roof individually using four twisting, movable jigs instead of the mid and end clamps that are commonly used in commercial installations.

Connecting the finished panels on floor 37 to the inverter on floor 34 required more than 90 metres of cabling. 6mm DC cable was needed instead of the standard 4mm to minimise losses over such a distance – one of the biggest the EvoEnergy team has ever traversed, as commercial project manager James Sutton explains.

“This has been a unique and challenging project, from the design stage through to project management, logistics, risk assessment and completion.

“We knew that delivering a rail-less system at that height would be a challenge, but we were confident that we could create the kind of bespoke solution to deliver it, of course also taking every necessary safety precaution along the way.

“The finished solar system, sitting high above the building’s stunning Sky Garden, looks fantastic. It’s been a job well done by the whole team from start to finish.”

The latest addition to London’s skyline, the ‘Walkie Talkie’ building 20 Fenchurch Street is being developed by Land Securities and Canary Wharf Group plc. Designed by award-winning architect Rafael Vinoly, it provides 680,000sq ft of office space with unrivalled views of the capital once completed. More than 90% of the space is let.


Quick Stats

  • Location Central London
  • System Size 50 kWp
  • Panel model Suntellite 200W
  • Inverter model Kaco
  • Anuual output 27,300 kWh
  • Annual CO2 savings 13,260 kg