The Comprehensive Assessment Of Energy-Environment-Economy Of Two Typical Agrivoltaic Systems In China

The agrivoltaic system combines agricultural production with photovoltaic power generation,which not only improves the efficiency of land space utilization,but also promotes the sustainable development of agriculture and power industries in remote areas.With the proposal of the Chinese carbon neutrality goal,the agrivoltaic system will be an important direction for future photovoltaic installations.Therefore,it is of great significance to comprehensively evaluate the agrivoltaic system in terms of energy,environment,and economy.However,domestic and foreign analysis of the agrivoltaic system mostly focuses on the impact of photovoltaic panel laying on crop growth,the environmental impact of the system,or economic analysis,etc.,and there are few comprehensive assessments of the entire system in terms of energy,environment,and economy.The comprehensive benefits of different forms of agrivoltaic complementary systems are relatively rare,and it is difficult to refer to the selection of suitable agrivoltaic systems in a specific area.Based on advanced hybrid life cycle assessment methods,this paper determines the system boundaries and functional units of the agrivoltaic system,establishes a calculation model and evaluation index system,and takes a 30 MW grass-light complementary system and a 20MW greenhouse-photovoltaic system in the Tibet Autonomous Region as examples.research.Through the collection and analysis of equipment,material,currency,and manpower data in the system construction period,operation and maintenance period,planting,and harvesting stages,a life cycle inventory related to fossil energy consumption,greenhouse gas emissions,water consumption and currency has been established.Calculate the system’s energy and water consumption intensity,greenhouse gas emission intensity,and economy,and finally use a combination of qualitative evaluation and quantitative analysis based on the analytic hierarchy process The two systems were analyzed and compared.The main conclusions are as follows:（1）In terms of life cycle energy consumption intensity,the energy consumption per unit area of the grass-light complementary system and the greenhouse-photovoltaic system are0.3417 TJ/hm²·yr and 0.4664 TJ/hm²·yr respectively,mainly from the construction period and the operation and maintenance period.The reproducibility indexes of the two systems are respectively 0.08 TJ/TJ and 0.18 TJ/TJ,both of which have strong reproducibility.（2）In terms of life cycle greenhouse gas emission intensity,the greenhouse gas emissions per unit area of the grass-light complementary system and the greenhouse-photovoltaic system are 42.87 t CO_2eq/hm²·yr and 60.41 t CO_2eq/hm²·yr respectively.The greenhouse gas emissions of the former mainly come from construction.Period and operation and maintenance period,the latter mainly comes from the construction period and planting period.（3）In terms of life cycle water consumption intensity,the water consumption per unit area of the grass-light complementary system and the greenhouse-photovoltaic system are3633.39 m3/hm²·yr and 9064.08 m3/hm²·yr,respectively.The direct water consumption and indirect water consumption of the grass-light complementary system accounted for 53.40%and 46.60%respectively.The direct water consumption and indirect water consumption of the greenhouse-photovoltaic system accounted for 25.57%and 74.43%respectively.（4）In terms of economy,The net present value of the grass-light complementary system is 274,147,300 CNY,the investment payback period is 1.89 years,and the internal rate of return is 59.30%;the net present value of the greenhouse-photovoltaic system is 157,552,400CNY,the investment payback period is 3.81 years,and the internal rate of return Is 32.90%.According to the criteria for judging the pros and cons of economics,the system has good economics,strong capital circulation and strong profitability.The levelized power generation costs of the two are 0.2749 CNY/k W·h and 0.4237 CNY/k W·h respectively,both of which are lower than the benchmark on-grid tariff for desulfurized coal in Tibet.（5）The qualitative results of the comprehensive evaluation show that the energy and environmental benefits of the grass-light complementary system are better than those of the greenhouse-photovoltaic system,and the economic benefits are slightly worse;the quantitative evaluation results show that the grass-light complementary system has three benefits in terms of energy,environment and economy.Both are better than the temperature and light complementary system,especially in terms of water consumption,investment payback period,and levelized power generation cost,which have obvious advantages.Based on the results of qualitative and quantitative evaluations,in the development of agrivoltaic projects in Tibet,the grass-light complementary system has more advantages than the greenhouse-photovoltaic system.This research compares and evaluates the comprehensive benefits of the grass-light complementary system and the greenhouse-photovoltaic system through a combination of qualitative and quantitative methods,and draws the conclusion that the development of the grass-light complementary system in Tibet has more advantages than the greenhouse-photovoltaic system.It provides strong data and theoretical support for the healthy development of photovoltaic agricultural system.