China could develop up to 863GW of floating solar and use this to help bring more green energy to areas such as Beijing where land is at a premium, according to a new study.

China should work harder on promoting floating solar to help “preserve scarce land resources” in its population-dense east and south, the researchers argued in their paper last month.

China accounts for around a third of global solar capacity and had 392GW installed by the end of 2022 (alongside 365GW of wind power).

Consultancy Rystad Energy expected China to top 500GW by the end of last year and hit 1TW by the end of 2026.

But the Chinese researchers behind the new paper, published in the journal Renewable Energy, said that traditional land-based PV suffers from a combination of “relatively low” power output and a scarcity of available land.

The high cost of land in urbanised areas furthermore “significantly affects the economic performance” of land-based solar.

Floating solar panels meanwhile tend to produce more power as they benefit from the cooling effect of the water bodies that they sit in.

Floating panels also don’t suffer from dust accumulation, as they are washed clean by the water.

The researchers found that, even if the initial investment cost is higher for floating solar, its “lifetime economic payback” can still outperform that of land-based panels in “some solar-abundant areas or provinces with higher electricity tariffs.”

The potential capacity for floating solar in China is 706GW–863GW, found the researchers. That would otherwise occupy 7,117 square kilometres of land.

While this is dwarfed by its land-based solar potential of 68TW, the researchers found that for several well-developed provinces the potential installed capacity for floating solar is “also more than ten times that of their existing installed capacity.”

The study did not compare the cost and viability of developing China’s floating solar potential with that of its offshore wind potential. That is estimated by the World Bank at almost 3TW between both fixed bottom and floating turbines.