Assessment of floating solar photovoltaic potential in China

Solar energy has expanded rapidly in recent years, and China is the largest market in terms of installed capacity. With the aim of achieving carbon neutrality by 2060, solar power will play an increasingly important role in China. However, like many other countries, the low energy density of solar photovoltaics is one of the major drawbacks of its further development. The emergence of floating photovoltaic systems (FPV) can not only break this threshold but also generate a series of cobenefits from a brand-new energy-land-water nexus perspective. Using a GIS-MCDA model, an evaporation model, combined with a cost-benefit analysis, this paper estimates the development potential of FPV in China, and its energy-land-water cobenefits are further analyzed. Moreover, to reveal the current land constraint for developing solar photovoltaics in China, the potential of traditional terrestrial solar photovoltaics has also been evaluated. The results show that the potential installed capacity of FPV in China can reach 705.2 GW–862.6 GW with an annual 1164.9 TWh to 1423.8 TWh of potential power output, and most potential FPV stations can obtain positive financial returns. The annual water evaporation reduction is approximately 5.8 km3. In the meantime, around 7117.3 km2 of the land could be conserved, which would alleviate the land constraint for terrestrial solar photovoltaic systems, especially in the highly urbanized eastern and southern coastal areas in China.