Floating solar

Floating solar or floating photovoltaics (FPV), sometimes called floatovoltaics, are solar panels mounted on a structure that floats. The structures that hold the solar panels usually consist of plastic buoys and cables. They are then placed on a body of water. Typically, these bodies of water are reservoirs, quarry lakes, irrigation canals or remediation and tailing ponds.
The systems can have advantages over photovoltaics (PV) on land. Water surfaces may be less expensive than the cost of land, and there are fewer rules and regulations for structures built on bodies of water not used for recreation. Life cycle analysis indicates that foam-based FPV have some of the shortest energy payback times (1.3 years) and the lowest greenhouse gas emissions to energy ratio (11 kg CO2 eq/MWh) in crystalline silicon solar photovoltaic technologies reported.
Floating arrays can achieve higher efficiencies than PV panels on land because water cools the panels. The panels can have a special coating to prevent rust or corrosion.
The market for this renewable energy technology has grown rapidly since 2016. The first 20 plants with capacities of a few dozen kWp were built between 2007 and 2013. Installed power grew from 3 GW in 2020, to 13 GW in 2022, surpassing a prediction of 10 GW by 2025. The World Bank estimated there are 6,600 large bodies of water suitable for floating solar, with a technical capacity of over 4,000 GW if 10% of their surfaces were covered with solar panels.
The U.S. has more floating solar potential than any other country in the world. Bodies of water suitable for floating solar are well-distributed throughout the U.S. The southeast and southern U.S. plains states generally have reservoirs with the largest capacities.
The costs for a floating system are about 10-25% higher than for ground-mounted systems. According to a researcher at the National Renewable Energy Laboratory (NREL), this increase is primarily due to the need for anchoring systems to secure the panels on water.
American, Danish, French, Italian and Japanese nationals were the first to register patents for floating solar. In Italy the first registered patent regarding PV modules on water goes back to February 2008.
The first floating solar installation was in Aichi, Japan, in 2007, built by the National Institute of Advanced Industrial Science and Technology.
In May 2008, the Far Niente Winery in Oakville, California, installed 994 solar PV modules with a total capacity of 175 kW onto 130 pontoons and floating them on the winery's irrigation pond. Several small-scale floating PV farms were built over the next seven years. The first megawatt-scale plant was commissioned in July 2013 at Okegawa, Japan.
In 2016, Kyocera developed what was then the world's largest, a 13.4 MW farm on the reservoir above Yamakura Dam in Chiba Prefecture using 50,000 solar panels. The Huainan plant, inaugurated in May 2017 in China, occupies more than 800000 m on a former quarry lake, capable of producing up to 40 MW.
Floating solar panels are rising in popularity, in particular in countries where the land occupation and environmental impact legislations are hindering the rise of renewable power generation capabilities.
Global installed capacity passed 1 GW in 2018 and reached 13 GW in 2022, mostly in Asia. One project developer, Baywa r.e., reported another 28 GW of planned projects.
Salt-water resistant floating farms are also being constructed for ocean use. They have the potential to reduce spatial pressures on land or lakes. Oceans of Energy (Netherlands) developed the world's first offshore solar system in the North Sea. Floating solar can have positive and negative effects on the ocean environment: for instance, it can act as an artificial reef and protect small fish and other animals. On the other hand, the floating panels increase shading and their construction may disrupt seagrass and coral reef.
Floating solar on Federally owned reservoirs in the United States has the potential to generate 1,476 terawatt hours annually. The shading from floating solar could help mitigate evaporation from reservoirs also.
The construction process for a floating solar project includes installing anchors and mooring lines that attach to the waterbed or shore, assembling floats and panels into rows and sections onshore, and then pulling the sections by boat to the mooring lines and secured into place.
There are several reasons for this development:
Floating solar presents several challenges to designers:
floating solar oppertunities in India