全球石油和天然气生产投资回报率初步调查——世界可经济开采的油气资源越来越少，人类应相应调整能源展望和经济发展目标

经济发展和能源密切相关,石油和天然气提供了世界能源消费量的近60％．但推动社会发展的能源必须具备储量丰富、能够开发,同时具有高投资回报率（EROI）的特点。文中利用美国、英国和JSH公司记录的油气生产相关数据,通过货币成本和能源成本转换等方法,计算得到全球油气生产的EROI值,1992年约为26：1,1999年上升至55：1,2006年下降至18：1,这意味着全球可经济开采的石油和天然气越来越少．人们应相应调整能源展望和经济发展目标。     

Energy return on investment, energy payback time, and greenhouse gas emissions of coal seam gas (CSG) production in China: a case of the Fanzhuang CSG project

The studies and development of coal seam gas (CSG) have been conducted for more than 30 years in China, but few of China’s CSG projects have achieved large-scale commercial success; faced with the boom of shale gas, some investors are beginning to lose patience and confidence in CSG. China currently faces the following question: Should the government continue to vigorously support the development of the CSG industry? To provide a reference for policy makers and investors, this paper calculates the EROI_stnd [a standardized energy return on investment (EROI) method], EROI_ide (the maximum theoretical EROI), EROI_3,i (EROI considering the energy investment in transport), and EROI_3,1+e (EROI with environmental inputs) of a single vertical CSG well in the Fanzhuang CSG project in the Qinshui Basin. The energy payback time (EPT) and the greenhouse gas (GHG) emissions of the CSG systems are also calculated. The results show that over a 15-year lifetime, EROI_stnd, ERO_Iide, EROI_3,1, and EROI_3,1+e are expected to deliver EROIs of approximately 11:1, 20:1, 7:1, and 6:1, respectively. The EPT within different boundaries is no more than 2 years, and the life-cycle GHG emissions are approximately 18.8 million kg CO₂ equivalent. The relatively high EROI and short EPT indicate that the government should take more positive measures to promote the development of the CSG industry.