Floating solar
PV arrays mounted on buoyant platforms on reservoirs, lakes, ponds or sheltered coastal waters instead of on land or roofs.
Floating photovoltaics (FPV) mount modules on high-density polyethylene floats or steel pontoons, anchored to the bottom or banks, with cables running ashore to an inverter station. The first commercial plants appeared in Japan around 2007; global capacity passed several gigawatts in the early 2020s, led by China, with large projects in India, South Korea, Indonesia and Europe. The 192 MWp Cirata plant in Indonesia (2023) is among the largest in Southeast Asia.
Advantages:
- No competition for land; useful near dense populations and in island grids.
- Reduced evaporation from reservoirs, which matters in arid regions.
- Water cooling can lower module temperatures; measured yield gains range from near zero to about 5% depending on design and wind exposure.
- Hybridisation with hydropower reservoirs lets plants share grid connections and use hydro to balance solar variability.
The World Bank report Where Sun Meets Water (2019) estimated a technical potential of over 400 GWp if just 1% of the surface of the world man-made reservoirs were covered.
Challenges include costs typically 10–25% higher than ground-mount PV, anchoring and mooring in waves, wind and changing water levels, corrosion and humidity effects on electrical components, and uncertain ecological effects on water quality and aquatic life at high coverage ratios. Offshore floating PV in sheltered seas (Netherlands, China, Singapore) is an emerging extension.
Related terms
All terms →- Agrivoltaics
The combined use of the same land for solar power generation and agriculture, such as crops or grazing beneath or between PV arrays.
- NOCT
Nominal Operating Cell Temperature: the temperature a PV module cells reach under 800 W/m², 20 °C ambient air and 1 m/s wind on an open rack.
- Pumped hydro storage
Energy storage that pumps water to an upper reservoir when electricity is cheap or abundant and releases it through turbines when power is needed; the largest form of grid storage worldwide.
- Albedo
The fraction of incoming solar radiation that a surface reflects, from 0 (absorbs everything) to 1 (reflects everything).
- Capacity factor
The ratio of the energy a power plant actually produces over a period to the energy it would produce running at full nameplate capacity for the whole period.