Floating solar technologies are creating major new opportunities to scale up solar energy around the world, particularly in countries with high population density and competing uses for available land.
The use of floating solar – deployment of photovoltaic panels on the surface of bodies of water – has grown more than a hundred-fold in less than four years, from a worldwide installed capacity of 10 megawatts at the end of 2014 to 1.1 gigawatts by September 2018, according to the first market report on floating solar, produced by the World Bank Group and the Solar Energy Research Institute of Singapore.
The report estimates the global potential of floating solar, even under conservative assumptions, to be 400 gigawatts – roughly the total capacity of all solar photovoltaic installations worldwide at the end of 2017.
“Floating solar technology has huge advantages for countries where land is at a premium or where electricity grids are weak,” said Riccardo Puliti, Senior Director for Energy and Extractives at the World Bank. “Governments and investors are waking up to these advantages, and we are starting to see interest from a wide range of countries in Africa, Asia and Latin America.”
At some large hydropower plants, covering just 3-4 percent of the reservoir with floating solar could double the capacity of the plant, potentially allowing water resources to be more strategically managed by utilizing the solar output during the day. Combining solar and hydropower can also be used to smooth the variability of solar output.
In a number of countries, floating solar also allows power generation to be placed more closely to urban areas or other demand centers. And while up-front costs are slightly higher, the costs over time of floating solar are at par with traditional solar, because of floating solar’s higher energy yield – due to the cooling effect of water.
In water reservoirs, floating solar panels can reduce evaporation, improve water quality, and serve as an energy source for pumping and irrigation.
Asia is the epicenter for this new technology’s expansion, with large floating solar plants at either the tens or hundreds of megawatt scale being installed or planned in China, India and Southeast Asia.
“We fully expect demand to grow for this technology and for floating solar to become a larger part of countries’ plans for expanding renewable energy,” said Puliti. “It will be important to ensure that best practices are shared among countries and development minimizes any environmental impacts.”
The market report is the first in a series of reports on floating solar – titled “Where Sun Meets Water” – being produced by the World Bank Group and SERIS, with funding provided by the World Bank’s Energy Sector Management Assistance Program and the Government of Denmark.