Floating solar photovoltaic (FPV) projects have been gaining attention in recent years. Occasionally referred to by the delightful portmanteau “floatovoltaics”, these systems function exactly as the name suggests – an array of solar PV modules are mounted onto floating platforms that are permanently moored in a body of water, usually a lake or ocean bay.
The number and capacity of these projects has been rising; analysis from consultancy firm Wood Mackenzie estimates that global floating solar capacity will cross the 6GW threshold as soon as 2031, the Asia-Pacific market having already hit approximately 3GW of floating solar projects in 2022.
A significant number of countries have put effort and investment into floating solar projects, with announcements from Belgium to Brazil, from Germany to Ghana, popping up almost weekly.
FPV installations have some major advantages over their land-based counterparts. Aside from offering a solar solution for places where available land is scarce, research from Bangor University and the University of Lancaster discovered that floating solar installations could reduce water loss from bodies of water during periods of extreme heat, and could also reduce the prevalence of damaging algal blooms in lakes. However, the UK has seen few floating solar projects take off, despite the potential they hold.
The current state of the UK sector
There are precious few floatovoltaic installations operating in the UK at present. The largest of them is a 6.3MW development on the Queen Elizabeth II reservoir, near London, with Nova Innovation’s Edinburgh development successfully powering Forth Ports’ headquarters since late 2023. Nova Innovation has since formed a joint venture with engineering specialist RSK, named AquaGen365, in an attempt to roll out more floating solar projects. Green Cat Renewables has also thrown its hat in the ring, asking Westmorland and Furness Council for a screening opinion on a potential 35-40MW project at Canvendish Dock, on the coast of Scotland.
Aside from these, and a handful of others, floating solar remains woefully underdeveloped as a sector in the UK. Despite the recent sixth auction round (AR6) of the UK government’s Contracts for Difference (CfD) funding landing record results, with 93 solar projects gaining support, no floating solar projects were funded.
The potential for floating solar in the UK
The Lancaster and Bangor University researchers looked at nearly 68,000 lakes and other bodies of water around the world and examined their potential output using historical weather data and future weather modelling. These researchers note that, if the UK took full advantage of its FPV potential – which the researchers defined as covering 10% of any eligible lake’s surface area with an FPV installation – the UK could produce as much as 2.7TWh of electricity each year from FPV. According to the most recent figures from the Department for Energy Security and Net Zero, the UK has around 16.9GW of installed solar capacity online as of the end of June 2024.
Another study, this time from the European Commission Joint Research Centre, highlighted the significantly increased benefits of pairing floating solar developments with hydropower reservoirs across Europe. Using just 2.3% of the total area of Europe’s hydropower reservoirs for floating solar installations could produce 42.3TWh of power each year.
Given that the UK has around 570 reservoirs (although not all of these produce hydropower), floating solar installations could provide a significant boost to UK energy security. According to the British Hydropower Association, the UK generates around 5.496TWh of hydroelectric energy each year across 1,657 installed hydropower schemes; installing floating solar in just a fraction of the water space from these schemes, which are already fitted with necessary power transmission infrastructure, would provide a significant power generation boost for the UK.
Furthermore, the benefits to biodiversity from floating solar could be significant. The positive impact of ground-mounted solar farms on biodiversity is well documented: studies run by Lancaster University and York University, and commissioned by Low Carbon and Solar Energy UK have gone so far as to declare ground-mounted solar farms “havens for biodiversity”.
While the effects of floating solar farms on biodiversity have yet to be fully examined, due to the sector’s relatively small presence in the UK renewable energy space, it has been noted that floating solar projects could help minimise the growth of algal blooms in large bodies of water.
In the Bangor University and University of Lancaster research paper, academics noted that algal blooms have been increasingly common in lakes around the world in recent years, something which can significantly decrease water quality and even cause health issues for those who use these water sources. FPV installations can prevent algal blooms from taking over a lake; by shading an area of the water, light can be limited and nutrient circulation prevented, significantly slowing the growth of algal blooms.
The FPV developments currently in operation or development have been designed with biodiversity in mind; Green Cat Renewable’s proposed design for its Cavendish Dock development features not only planting native wildflowers and other plants on the land surrounding the site, but also adding enhancements for coastal waterbirds, including seabird nesting rafts and additional roosting structures.
However, it’s clear that further research into the impact is needed; in a press release launching the aforementioned paper, its lead author Dr Iestyn Woolway of Bangor University said: “We still don’t know exactly how floating panels might affect the ecosystem within a natural lake, in different conditions and locations. But the potential gain in energy generation from FPV is clear, so we need to put that research in place so this technology can be safely adopted.”
While floating solar projects offer immense potential for renewable energy generation, water conservation, and biodiversity enhancement, the sector remains underdeveloped in the UK. The benefits of FPV, from reducing water loss and curbing harmful algal blooms to enhancing energy security, are clear.
Yet, the lack of investment and research, especially in understanding the ecological impact of these installations, has hindered the widespread adoption of this technology. If the UK is to fully realise the potential of floating solar, there needs to be a concerted effort to boost uptake of this tech- not to mention an uptick in research, policy support, and industry investment. Only then can the UK tap into the significant advantages FPV offers and contribute meaningfully to its renewable energy goals.
