Author: Toni Weigl, BayWa r.e.
By Toni Weigl, Product Manager Floating-PV, BayWa r.e. Solar Projects GmbH
In order to meet crucial climate targets, we must expand the renewable generation mix. Solar energy is key to this, being an extremely flexible renewable energy source as it works in a range of environments. Ground-mounted solar installations are already familiar, and the technology is highly efficient in terms of performance and production costs, making grid parity a reality. In order to extend the enormous potential of solar energy, Floating-PV is a promising solution that has an important role to play. Today, BayWa r.e., the market leader and full-service provider of Floating-PV, has built more than 100 MWp in Europe. However, the unrealized potential of this technology remains vast.
The World Bank estimates that there are 400,000 square kilometers of man-made reservoirs around the world. If converted to Floating-PV, this space has a theoretical energy production potential on a terawatt scale. A more humble goal shows that in Europe alone, accommodating Floating-PV on just 10 percent of freshwater reservoirs would create around 200 GWp*.
The potential for growth in Floating-PV is considerable. However, the application of this technology is still new. In order to take Floating-PV to the next level and beyond its current role as a niche contributor to global renewable energy production, one important topic must be further explored and evaluated: the environmental impacts of Floating-PV.
BayWa r.e.’s Tynaarlo Floating-PV park
One of Floating-PV’s greatest benefits is its simplest. By using unused bodies of water—from disused coal quarries and mineral extraction pits to reservoirs—it can make an important contribution to the green energy revolution without competing against other uses for land. This makes it an attractive solution for high-population density localities, for example in Europe, where there are heated debates at the EU-level over how land should be used by member states.
Not only does Floating-PV save on land space, but the solar panels can also provide surface shade and water cover, reducing water evaporation. For countries facing water shortages, this can be particularly valuable—it’s estimated that currently, more water evaporates from reservoirs than is consumed by humans. Water quality can also be improved, with the panels discouraging the growth of certain algae.
Before any installation takes place, however, it’s important that Floating-PV can integrate into the landscape on an aesthetic and practical level. Floating-PV arrays do not have a high visual impact as they are more likely to blend in with the surface water where they are located. Nevertheless, community outreach and alignment are vital in ensuring Floating-PV makes a positive impact on the local environment and population. Ahead of a project’s construction, many information evenings, personal discussions and feedback opportunities are organized with local residents and associations to ensure a collaborative approach to the project. Neighbours to BayWa r.e.’s Tynaarlo Floating-PV park are testament to this.
While the need for green infrastructure is clear, its creation should not come with unnecessary climate costs. The building of green infrastructure should instead be a chance to champion best practices and demonstrate the potential of carbon-free construction.
BayWa r.e. is taking steps towards a 100% carbon-free construction of all its solar parks. Our recent Floating-PV parks have been built using their own generated electricity. By combining ‘satellite’ solar parks with the use of high-capacity batteries, in terms of energy, the construction can become entirely self-sufficient. This can drastically cut carbon emissions and costs compared with traditional methods, while meeting or exceeding climate related construction regulations or guidelines.
Once a plant is constructed, to create a clear picture of Floating-PV’s environmental impact we need to understand how it affects biodiversity. Until recently, little has been known as the application of this technology is still new. As its use expands and more research is carried out, this is beginning to change.
It’s important to note that certain bodies of water—for example disused sandpits or quarries—suited to Floating-PV do not host much marine life at all. However, for those with a greater array of flora and fauna, BayWa r.e. is cooperating with several institutes conducting research into how Floating-PV impacts biodiversity.
At the company’s current flagship project, Bomhofsplas, ‘bio huts’ made by Ecocean are being submerged beneath the floating solar panels, filled with seashells to potentially encourage marine life and greater biodiversity. Meanwhile, ongoing tracking and assessment of water quality, with samples taken before and after installations, provides data on the overall impact of the installation. In the longer-term, BayWa r.e. is also working with experts from environmental consultancies at certain sites, to see how plant life and biodiversity is affected on a 5-year scale.
Bio huts at Bomhofsplas Floating-PV park
While there is much to learn, initial assessments of Floating-PV are promising. When using BayWa r.e.’s boat structures for the floating systems, there is currently little reason to believe biodiversity will be adversely affected. This is because only 15 % of the system’s total size has direct water contact footprint, allowing free water movement and avoiding polysabrobic water.
As Floating-PV becomes more commonplace, monitoring and assessing its environmental impact will be key to demonstrating how this innovative application can play an increased role in the renewable space, while also benefiting marine areas and encouraging biodiversity.
Floating-PV is an innovative application form of a well-established technology. It will continue to evolve, and thanks to the falling cost and an increased understanding of the benefits of the application, the future for Floating-PV is bright. While Japan, China, and the Netherlands have taken an early lead in the sector, Floating-PV is expanding into Germany and France, and will also get to southern Europe, as a technically and economically feasible complement to other PV applications such as standard ground-mounted PV or Agri-PV systems.
Ongoing research into the environmental impact of Floating-PV will be vital in understanding and unlocking its potential through continued innovation, as well as constant development and improvement. In terms of green energy production via the use of otherwise unused bodies of water, the benefits are clear. Beyond this, Floating-PV can create new jobs and industry in everything from business and design to construction and maintenance, boosting local economies and strengthening communities.
For now, it’s clear Floating-PV has an exciting role to play in accelerating global production of renewable energy across a range of countries and markets. The costs of installations will fall as technology and construction methods mature, as well as through economies of scale. Meanwhile, the benefits, from promoting clean energy, reducing water shortages and improving biodiversity, through to job creation, have only just begun.
Here you can learn more about “The next generation of floating solar power”.
Where Sun Meets Water: Floating Solar Market Report, International Bank for Reconstruction and Development / The World Bank, 2019, table 3.1, page 57.