Removing the weight issue from solar retrofits
20 November 2025
Ciaran Cotter explains how lightweight solar solutions can help overcome some of the key challenges associated with retrofit commercial applications and help businesses unlock some of the big benefits of solar energy.
As the global push for renewable energy gains momentum, the UK’s enormous yet largely untapped solar opportunity continues to come under sharpened gaze – and for very good reason. With 350 million square metres of warehouse space available alone, transforming these rooftops into solar self-generation hubs could play a pivotal role in reducing fossil fuel reliance and expanding clean energy generation.
Embracing solar also translates to substantial cost savings. In fact, by fully utilising the available rooftop space it is estimated that commercial buildings could save £35 billion. In energy generation terms that translates to 117 TWh of electricity annually. That’s enough to power approximately 30 million homes for a year, more than the number of households we currently have in the UK. So, the big question is – why are less than 5% of the UK’s commercial and industrial rooftops equipped with solar?
Though there may be a myriad of reasons, such as financial barriers or policy and regulatory uncertainty, in our experience it usually comes down to one – roof suitability and structural limitations.
Many of the commercial and industrial buildings that we have here in the UK were constructed long before solar technology became a viable energy solution, meaning they were not designed to accommodate traditional, rigid-form solar panels. A lot of these structures have roofs that are not able to handle the weight and load of solar panels, especially older buildings with existing HVAC systems taking up valuable space.
It’s also common for commercial buildings to have irregularly shaped roofs with unusual layouts, curves, slopes or obstructions, bringing further installation challenges. The result is that, in many cases, it simply isn’t possible to install traditional solar panels, without the need for steel reinforcements which can be costly and complex to install.
To place it into context, it’s estimated that up to 45% of commercial buildings cannot support the weight of traditional solar panels. The good news in 2025 is that we now have an innovative lightweight solar system which offers a fraction of the weight of standard solar, and the impact for operators and the green economy could be profound.
Case studies
At Solivus, we’ve installed solar on airports, stadiums, warehouses and more. In my experience, the only regret that most commercial operators have is not going solar sooner.
A great example of this still largely untapped opportunity can be found in our recent work with Europe’s leading private aviation destination: Farnborough Airport. As part of its strategy to achieve net zero by 2030, Farnborough Airport sought to reduce electricity and gas usage and invest in onsite renewable production. However, the iconic architectural curves of the airport building, as well as its low load capacity meant that traditional rooftop solar was not an option.
The solution to overcoming these challenges and installing the desired solar was found in our pioneering lightweight solar solution. Now complete, the installation, which commenced works in January 2024, has seen over 4,000 lightweight solar panels installed on hangars one and two, the terminal, the control tower, and the Airport’s award-winning 169-room hotel, the Aviator Hampshire.
Constituting one of the largest rooftop solar installations in the region, the works will enable up to 25% of the airport’s annual electricity needs to be met, as well as enabling its growing operational fleet of electric vehicles to be charged using self-generated electricity. With approximately 75% of solar energy generated to be used on site, the remaining 25% will be sold back to the energy supplier, thus making the financial case for solar even more attractive.
Our work with Northampton County Cricket Club (NCCC) is equally compelling. As part of its commitment to sustainability, the club sought to take advantage of the self-generation opportunity afforded by solar but there was a problem – like many sports centres and stadiums, the stadium wasn’t able to take the weight of traditional glass solar panels.
We were able to solve this with lightweight solar systems – which are up to 70% lighter than traditional panels yet provide an equally powerful performance – in a bespoke end-to-end project constituting a total of 221 lightweight solar panels. Eighteen months since the project’s commissioning date and initial operational data reveals the installation has seen total estimated savings for NCCC of over £20,000, with an annual ROI of 10.8%. To date, the installation has saved over 15,900 kg of CO₂e.
Join the revolution
The government has a clear target to increase solar capacity by nearly fivefold to 70GW by 2035 as part of wider plans to power up Britain with cleaner, cheaper and more secure energy sources. Unlocking the commercial solar opportunity will be a critical enabler.
With advancements in solar technology continuing at a rapid pace, there is a huge opportunity for commercial and industrial premises to take advantage of the vast opportunity on existing infrastructure, reduce emissions and costs, futureproof and play a role in helping to accelerate the clean energy revolution.
