Why Floating Solar
There are several benefits to Floating Solar over ground mounted Floating Solar . Some of them are listed below.
No land occupancy: The main advantage of floating PV plants is that they do not take up any land, except the limited surfaces necessary for electric cabinet and grid connections. Their price is comparable with land based plants, but they provide a good way to avoid land consumption.
Installation and decommissioning: Floating PV plants are more compact than land-based plants, their management is simpler and their construction and decommissioning straightforward. The main point is that no fixed structures exist like the foundations used for a land-based plant so their installation can be totally reversible.
Water saving and water quality: The partial coverage of basins can reduce the water evaporation. This result depends on climate conditions and on the percentage of the covered surface. In arid climates such as Australia this is an important advantage since about 80% of the evaporation of the covered surface is saved and this means more than 20,000 m3/year/ha. This is a very useful feature if the basin is used for irrigation purposes.
More Energy Yield: The floating structure allows the implementation of a simple cooling system. Cooling mechanism is natural but can also be active by generating a water layer on the PV modules or using a submerged PV modules, the so called SP2 (Submerged Photovoltaic Solar Panel). In these cases the global PV modules efficiency rises thanks to the absence of thermal drift, with a gain in energy harvesting up to 8-10%.
Tracking: A large floating platform can be easily turned and can perform a vertical axis tracking: this can be done without wasting energy and without the need for a complex mechanical apparatus as in land-based PV plants. A floating PV plant equipped with a tracking system has a limited additional cost while the energy gain can range from 15 to 25%.
Storage opportunity: The presence of water naturally suggests using gravity energy storage mainly in the coupling with hydroelectric basins. However other possibilities has been explored and in particular CAES systems have been suggested.
Environment control: A parallel advantage is the containment of the algae bloom, a serious problem in industrialized countries. The partial coverage of the basins and the reduction of light on biological fouling just below the surface, together with active systems can solve this problem. This is only a part of the more general problem of managing a water basin generated by industrial activities or polluted by them. See for example the mining managing.
Efficiency improvement: Many studies claim that there is a significant improvement in efficiency putting solar panels over water. These studies are not conclusive and differ in their conclusion. The energy gain reported range from 5 to 15%.