Challenge
We were tasked with completing one of the UK’s highest solar panel installations on top of London’s 38-storey skyscraper at 20 Fenchurch Street.
Because of space restrictions, materials could only be moved on to 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 our 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.
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 its location in the heart of the City of London, a series of bespoke engineering and logistical solutions were required.
our solution
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 times – 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.
The Result
Once completed, in order to connect the panels on floor 37 to the inverter on floor 34, the project required more than 90 metres of cabling. Additionally, 6mm DC cable was needed instead of the standard 4mm to minimise losses over such a distance.
This was certainly 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, whilst taking every necessary safety precaution along the way.
The 250-panel, 50 kWp PV system was fitted to the roof of the building during summer months. Now finished, it’s in the top 10 list of highest solar arrays in the country (as of date of publish).