Benefit evaluation of multi-energy complementary projects in Qinghai province: a case study of project F

By constructing a benefit evaluation system for multi-energy complementary projects, utilizing ecological value accounting, remote sensing inversion, and cost-benefit analysis, this study explores the actual and spillover benefits of such projects in Qinghai Province, using the F project as a case study. The research findings over a 25-year period reveal the following: (1) The F project achieved a carbon emission reduction of 37.9625 million tons, with a reduction value of 2.24 billion yuan, and a carbon sequestration and oxygen release value of 77,282.39 yuan, indicating significant ecological benefits. (2) Remote sensing data analysis of vegetation coverage during different operational periods of the project shows a notable decrease in decertified land area and an increase in the photovoltaic-grassland system area. (3) The total cost of the F project was 14.7336 billion yuan, with total revenues of 21.8781 billion yuan, resulting in an investment return rate of 48.49%, indicating considerable profitability. However, there is an overreliance on government subsidies. (4) Ecological costs accounted for 1.03% of the total cost, while the benefits and spillover values accounted for 12.06% and 34.79% of the total value, respectively, suggesting that the ecological benefits of the multi-energy complementary system have substantial potential.