Estimates suggest that the global potential of floating solar could be 400 GW, or roughly the total capacity of all solar PV installations worldwide at the end of 2017.
Floating solar – the installation of solar photovoltaic panels floating on the surface of lakes, hydropower reservoirs, agriculture reservoirs, industrial ponds, and near-coastal areas – is one of the fastest-growing power generation technologies today. It opens new horizons to scale up solar power globally, particularly in countries with land constraints.
The capacity for floating solar is growing exponentially. At the end of 2014, total global installed capacity stood at 10 MW. In just four years, that figure had grown more than 100-fold, to 1.1 GW. The new report estimates the global potential of floating solar, even under conservative assumptions, to be 400 GW, or roughly the total capacity of solar photovoltaic installed worldwide at the end of 2017.
The greatest advantage of floating solar is that it avoids land acquisition and site preparation issues associated with traditional solar installations. In some cases, floating solar allows for power generation to be sited much closer to areas where demand for electricity is high. This makes the technology an attractive option for countries with high population density and competing uses for available land.
Floating solar also complements existing hydropower infrastructure. At some large hydropower plants, only 3-4 percent of the reservoir would need to be covered with floating solar panels to double the electricity generation capacity of the dam. In addition, combining hydropower and solar power outputs can help smooth the variable nature of solar power. The technology can also help manage periods of low water availability by using solar capacity first and drawing on hydropower at night or during peak demand. In agricultural reservoirs, the solar panels can reduce evaporation, improve water quality, and serve as an energy source for pumping and irrigation.
While up-front costs are slightly higher, the costs over time of floating solar are at par with traditional solar PV, because of floating solar’s higher energy yield due to the cooling effect of water.
The technology is particularly promising for fast-growing Asian economies. Interest is growing rapidly in the region, and large plants are being installed or planned in China, India and Southeast Asia.
Overcoming the challenges
Still, some challenges exist including the lack of a long-standing track record, possible effects on water quality, complications related to the anchoring and mooring of installations, and the relative complexity of maintaining some parts of the installations – electrical components, in particular.
Despite these challenges, floating solar offers significant opportunities for the global expansion of solar energy capacity.
Meet the EU’s largest floating solar plant
On Friday 21st October in the commune of Piolenc, in the department of Vaucluse in southern France, people gathered to witness the inauguration of Akuo Energy’s new 17 MW floating solar power plant.
Situated on a lake in a former quarry, the O’MEGA1 project is the largest of its kind in Europe. It consists of 47,000 solar modules using the Hydrelio technology developed by the French floating PV specialist Ciel & Terre. The modules are made from recyclable high-density polyethylene, built to withstand winds up to 210 km/h.
The floating plant has been in development since 2014, with Akuo working in tandem with the quarry operators to ensure a smooth transition. Spread across 17 hectares, the annual production of the plant will provide 100% renewable energy to 4,373 households, saving at least 1,093 tonnes of CO2 every year.
Interestingly, the project was partly financed through crowdsourcing, supplementing investment from Natixis Energéco. Further, the municipality of Piolenc itself chose to invest, meaning that the community is set to benefit from the project’s success. This kind of symbiotic relationship between a PV developer and local community could represent a sustainable business model moving forward.