Ciaran Cotter, technical director at lightweight solar pioneer Solivus explains the issues of retrofitting solar panels.
At one point, the concept of installing solar panels onto existing commercial or industrial infrastructure may have seemed an almost impossible task due to complexities associated with roof type, weight and windage, and potential structural reinforcement needs.
However, this is now changing as the latest generation of lightweight solar is revolutionising the self-generation opportunity for existing commercial premises.
On the surface, it would appear that the rooftop revolution is indeed upon us. Thanks to a combination of factors such as government support, falling costs, and rising electricity prices, recent years have seen domestic solar installations in the UK grow at an unprecedented rate. As of March 2025, around 1.5 million UK homes have solar panels, a massive increase from just 28,211 in 2010.
Notably though, while there may be no doubting the significance of the residential solar market, there is an arguably even more important yet largely overlooked opportunity – commercial solar. The vast, unused roof spaces available on our schools, warehouses, factories and the like offer a huge self-generation opportunity. In fact, by fully utilising the available rooftop space it is estimated that commercial buildings could save £35 billion and create enough energy to power approximately 30 million homes for a year. Yet, according to a recent analysis less than 10% of the UK’s non-domestic buildings are utilising their available rooftop space for solar energy despite such significant benefits.
But why you may ask?
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 other 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 40% 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 has more universal applications for fixing methods which have opened up new roof space opportunities.
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’s wasn’t able to take the weight of traditional glass solar panels.
We were able to solve this in lightweight solar systems - which are up to 70% lighter than traditional panels yet provide an equally powerful performance, also with a 25 year lifetime warranty – 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.
It’s clear that commercial solar must play a central role in the energy transition, as a way for companies, particularly those operating largescale industrial and commercial premises, to save costs, reduce emissions, and improve resilience and sustainability.
By leveraging the latest innovations in lightweight solar technology today, businesses can help play a leading role and reap the biggest benefits while remaining tomorrow-ready.