Exploiting the Full Performance Potential of (Offshore) Floating Photovoltaics through Thermal Approaches: an Overview of Options

Floating photovoltaics (FPV) unlocks scalability for PV systems where onshore space is scarce. The technology reached an installed capacity of 2.6 GW in 2020 and has demonstrated accelerated growth since then [1], reaching 5.6 GW in 2022 [2]. Floating PV is rapidly gaining maturity for ponds and lakes, and the exceptional decrease of PV module prices is creating possibilities for offshore floating PV (OFPV) as well. Several OFPV pilot installations are now operational at sea [3], [4], [5]. (O)FPV could take advantage of its unique environment in several ways. From a thermodynamic point of view, the photovoltaic energy conversion on floating PV systems creates a heat source raised above a massive thermal reservoir at lower temperature. In the case of a lake or the sea, this means that enormous amounts of heat can be taken up by the underlying water without significant changes in its temperature. While current OFPV systems make passive use of this thermal gradient, possibilities for active exploitation of this thermodynamic potential can also be considered. Compared to onshore PV, large amounts of heat can efficiently be disposed of through the water beneath floating PV systems, which creates a larger potential for the integration of heat engines and active cooling approaches. This work briefly outlines the theoretical and technological potential of these two performanceenhancing methods for floating PV.