After 4 years of extensive discussion and bespoke design, the first of 150 solar PV panels are to be installed on Gloucester Cathedral. It comes at a pivotal stage when, for the first time in history, solar panels are overtaking coal stations in supplying the country’s demand for electricity. With our careful and responsible approach, we’ve ensured that it is possible for even Grade I listed buildings to make conscious efforts to make the switch to renewable energy.
The Cathedral will see a 25% annual reduction in energy costs by installing the 150 REC Twin Peak 280wp solar panels onto the south facing Nave. This is an active step toward supporting The Church of England in its ‘Shrinking the Footprint’ campaign, which outlines the Church’s plans to address climate change.
This project was first brought to our attention in 2012, where we discussed with the appointed architects about the feasibility of adding solar to the 30m high Nave. We worked closely with the architects, advising them on a suitable design for the mounting system that would be both responsible and respectful to the historical building. This meant reducing as much as possible, the visual and practical impact of modern technology on traditional aesthetics.
During this same time period, the architects were commissioned to design a new ridge capping for the Nave to allow greater roof ventilation. This created an ideal platform for us to develop a bracket that would hook over and be securely fixed to. Using a mixture of hand drawings, AutoCAD plans and Solidwork details, we were able to establish a clear installation methodology.
The specialist bracket is produced from a single piece of 5mm thick stainless steel, which is bent into shape to accommodate the correct angles of the ridge capping and slope of the nave. A single piece of our strongest mounting rail is then bolted to the bracket in 5 positions to create the base layer. There will be a total of 60 brackets spaced along the ridge capping holding the base rails in place. With our efficient supply chain, we were able to manufacture and deliver these brackets to site within 7 days.
Separation material will be laid underneath the base layer where it comes to rest against the lead roof to ensure further protection of the existing Nave’s construction. A secondary layer of mounting rail is then attached across this base layer, which provides a clamping platform for the solar panels.
The competitive tendering process for the installation took place in the early part of 2016, with the contract being awarded to the Gloucestershire based solar installer, Mypower. Through our long standing partnership with Mypower, we could join together our skills to give a detailed and thorough overall project design. Mypower took the lead in developing a comprehensive shading analysis and specifying the use of Solar Edge invertors with Optimisers to off-set any potential loss of performance.
While providing on-site support in cooperation with Mypower, installation of the solar panels is hoped to be completed by early November.