A group of Chinese researchers evaluates the effect of floating solar power systems on radiation, energy flow and the driving forces of lakes in variable weather conditions. It found that the contribution of the PV system to the sensible heat flow of the lake is 1.5 times greater than that of a natural lake.
The novelty of their approach, they said, is the analysis of radiation and energy balance characteristics of floating solar power plants under different synoptic conditions, which previous studies reportedly overlooked. “Our study fills this research gap, perhaps to change the accuracy of solar radiation prediction, as our paper takes into account the influence of weather conditions on solar radiation,” they explained.
The experiment was conducted at the Tongwei Huantai 10 MW Fishery Complementary Photovoltaic Demonstration Base in Yangzhong, a city in Jiangsu Province, east China. Two flux observation towers – one inside the floating solar power plant (FPV) and one outside (REF) – collected data over three days in different weather conditions, recording and comparing changes in radiation and energy flux at the two sites.
According to the researchers, the effect of the floating group on the sensible heat flux is 1.5 times that of a natural lake, which they say means that solar radiation plays a decisive role in the sensible heat flux change process. In fact, they found that the contribution of solar radiation to the FPV region was 98%, while the contribution to the REF region was 77%.
The data showed that the driving force for sensible heat flow at the floating solar PV system site controlled the temperature of the solar panels, while the driving force for latent heat flow – in both sunny and cloudy conditions – was wind speed multiplied by the water-air vapor pressure deficit.
“Overall, the latent heat flux (LE) in the two locations was relatively stable, and the sensible heat flux (H) in the FPV region exhibits more pronounced fluctuations than the REF region during solar radiation,” the report said. . “This phenomenon is explained by the fact that the air temperature in the FPV area rose faster than the air temperature in the REF area due to the heating effect of the PV panel when receiving sunlight.”
Because the lake’s photovoltaic systems create a new bottom surface, the team found that the differences in radiation across these covered surfaces are due to the effects of aerosols, water vapor, terrain, and weather conditions on sunlight.
The effects of the floating system were also found to be related to the scale of the power plant. “The effects of utility-scale floating solar power plants on radiation and energy flow still need to be investigated,” the researchers conclude.
Their findings are available in the report “Effects of Fisheries Complementary Solar Power on Radiation, Energy Flow and Driving Forces under Different Synoptic Conditions” published in Scientific reports.