I'll go with the satellite measurements and the law of conservation.
5. Conclusions and discussion
By analyzing MODIS retrieved surface reflectances over the six solar-farm sites as well as their neighboring control sites, we show that the changes due to solar panel installation can be detected in surface spectral reflectances at the MODIS Bands 1–7. The case study with the DSSF site shows a 20%–25% reduction of surface reflectances at the seven MODIS bands. Radiative transfer calculation suggests that such a reduction of surface reflectance can lead to a ∼23% decrease in surface upward shortwave flux and a ∼14%–18% decrease in TOA clear-sky reflected shortwave flux.