Soil carbon loss from building photovoltaic power stations is under 2 % of their carbon reduction.

Scholars worry that the construction of photovoltaic power plants may result in higher carbon emissions and hinder global carbon neutrality goals. To address these concerns, we established eight observation stations in China to conduct long-term monitoring of meteorological indicators under and between the photovoltaic panels, as well as on natural land outside the plants, while sampling vegetation and soil. Using the Denitrification-DeNitrification Computation(DNDC) model, we simulated and validated the carbon cycling processes of the photovoltaic power plants based on observational data. The results indicate that the construction of photovoltaic power plants reduces soil carbon storage, with the values under and between the photovoltaic panels at 58.90 % and 65.40 % of that of the natural land outside the plants, respectively. Meanwhile, photovoltaic panel coverage significantly suppresses soil carbon emissions, with emissions under and between the photovoltaic panels at 38.80 % and 53.22 % of those of the natural land outside the plants, respectively. In the long term, photovoltaic power plants do not lead to a significant increase in carbon emissions and may even slow the carbon emission processes of the original ecosystem, particularly with a notable 53.99 % reduction in CO2 compared to that in the natural land outside the plants. From the life-cycle perspective of photovoltaic power plants, although the construction of photovoltaic power plants leads to soil carbon loss, the amount of loss accounts for less than 2 % of the total carbon reduction achieved during their operational period.