Energy, environmental, and socioeconomic potential benefit of straw resources utilization under water availability limit condition

Abstract

Lots of straw resources are abandoned or burned in the open in China. It not only discharges harmful gas and carbon dioxide into the air, but also wastes huge energy. Irrigation water availability is a key factor that influences the crop yield and corresponding straw resources which is facing a severe crisis in most regions around the world. Therefore, it is very essential to conduct research about the potential benefit of utilizing straw resources from future water availability limit perspective. Xi'an City is taken as an example which is the most developed city in the west of China. This study predicts the future crop yield, and assesses the potential energy, environmental, and socioeconomic benefit of two major straw resources including winter wheat and summer maize under 6 water availability scenarios. Sensitivity analysis is further carried out for the impact of feed-in-tariff and material cost on the biomass power plant revenue and critical value determination. Key results include (1) the straw resources could generate about 5.65 × 108 kWh electricity, save about 24.33 × 104 ton raw coal, and reduce 48.12 × 104 ton carbon dioxide emission; (2) Farmers could gain about 1.35 × 108 CNY; (3) Conversion from thermal to biomass power plant could generate net benefit about 1.89 × 108 CNY considering the electricity selling benefit increase about 2.24 × 108 CNY, carbon dioxide emission cost reduction about 0.72 × 108 CNY, material purchase cost increase 0.69 × 108 CNY, and other input cost increase 0.38 × 108 CNY; (4) Higher water availability leads to more energy, environmental, and socioeconomic benefit; (5) Feed-in-tariff has to increase about 0.012 CNY/kWh for every 10 CNY/ton material cost increase to ensure the positive benefit of biomass power plant. In general, effective utilization of straw resources can not only increase farmers' income and power plant benefit, but also reduce fossil energy use and protect the environment.