Abstract:Quantitative assessment model of low cost element is first established by dividing rural energy system cost into economic cost and environmental cost.And the latter is determined based on output data of life cycle inventory.With 15 years as a life cycle,12 energy system schemes of 3 typical villages from freezing zone,cold zone in China are compared synthetically as case studies.From the quantitative result,the fossil energy(coal,LPG) system schemes have higher economic and environmental cost; straw and fuel wood energy system schemes have lower economic cost but higher environmental cost; straw gas and methane energy system schemes have lower economic and environmental cost,and the integrated cost is below 5 000 yuan·capita-1,which are the optimum schemes for the future rural energ