中国中长期碳减排战略目标初探(Ⅶ)——中国能源需求暨碳排放情景分析讨论

A Preliminary Study on China′s Long and Medium-Term Strategic Goals for Reducing Carbon Emissions(Ⅶ)——An Analysis and Discussion on China′s Energy Demand and Carbon Emission Scenarios

预测世界二氧化碳排放量峰值40Gt／a出现在2025年，此后年均下降4．1％，2050年才能达到IEA Blue Map情景要求的14Gt／a，届时人均排放量为1．5t，由于总降幅未达到80％，仍需努力减排，争取2070年世界二氧化碳排放量达到10Gt／a。中国2005～2025年累积二氧化碳排放量约160Gt，2025～2050年间约194Gt，2050—2070年间约75Gt．2005～2070年间合计约472Gt，约占当时世界份额的27％。希望中国碳排放峰值出现在2025年而不是2030年。即使能控制当年二氧化碳排放量达到10．5Gt／a的水平，此后年均下降2．9％，2050年达到5Gt／a的较高水平，年人均排放量降低到3．4t，仍高于世界均值。为了与世界总降幅同步，还需要进一步减排，争取2070年二氧化碳排放量达到2．5Gt／a。为了在2050年达到期望的碳减排目标，必须优化中国的产业结构和能源结构，发电、钢铁、水泥是中国节能减排的重点。受生物质资源不足、煤化工生产油品只能适度发展、氢燃料替代目前尚无确切时间推广节点的制约．预计2050年中国替代石油燃料的比率在20％左右，低于欧美地区50％～70％的比率。但通过提倡绿色出行、提高发动机燃油效率、乘用车过渡到以纯电动汽车和混合动力汽车为主、石油替代步伐加快且替代方式多样化、提高石油加工轻质化程度、加大天然气在CHP或DES／CCHP的高效利用等措施，将2050年的原油消费量控制在6．0×10^8t仍然有可能。加工6×10^8t原油可生产1．08×10^8t化工轻油，CBTL生产的油品总量中还包含1200×10^4t石脑油，合计化工轻油量为1．20×10^8t，加之还可由煤化工MTO／MTP生产一定量的烯烃，可满足基本有机化工原料的需求。只有通过各部门的综合努力，低碳排放的A或B情景才有可能实现，任何部门的牵制都将影响全国碳减排目标的实现。

The world＇s carbon dioxide emissions are expected to peak in 2025 ,at 40Gt/a,and then to drop at an annual rate of 4.1%,to 14Gt/a required in IEA＇s Blue Map scenario until 2050.At that time,the world＇s per capita carbon dioxide emission would be 1.5t.As the overall objective of reducing the emissions by 80% were not met ,more efforts should be made to try to reduce the world＇s carbon dioxide emissions to 10Gt/a by 2070.The cumulative volume of carbon dioxide emitted by China during 2005 to 2025 would be around 160Gt,around 194Gt during 2025 to 2050,and around 75Gt during 2050 to 2070.The total amount of carbon dioxide emitted by China during 2005 to 2070 would be around 472Gt,about 27% of the world＇s total at that time.We hope China＇s carbon emissions to peak in 2025 ,not in 2030.Even if China＇s peak carbon dioxide emissions could be controlled on the level of 10.5GT/a and could thereafter drop at an annual rate of 2.9%,the emissions would still reach 5Gt/ a by 2050,equivalent to 3.4t per capita, still higher than the world＇s average level.To keep pace with the world＇s average drop in emissions ,China should step up its effort to cut emissions and strive to reduce carbon dioxide emissions to 2.5Gt/a by 2070.To meet its expected carbon emission reduction ob- jectives by 2050,China must move to optimize its industrial structure and energy mix.The power generation ,iron and steel and cement industries would be the focus of China＇s energy saving and emission reduction drive.Due to a combination of factors such as insufficient biomass resources ,the limited room for development of coal-derived oil products and the absence of a timetable for the wider use of hydrogen as a feasible alternative fuel, the share of alternative fuels to petroleum used in China is expected to reach only about 20% by 2050,lower than the shares of 50%-70% in Europe and the United States.However,it is still possible for China to control its crude oil consumption around 6.0×10^8t by 2050 by encouraging people to reduce the use of motor vehicles, raising fuel economy for engines, using battery electric vehicles or hybrid vehicles as the main passenger vehicles, quickening the pace of replacing petroleum ,diversifying sources of alternative fuels to petroleum ,raising the share of lighter products produced in oil processing and increasing the efficient utilization of natural gas in CHP or DES/ CCHP.Processing 6×10^8t of crude oil can output 1.08×10^8t of naphtha and the oil product production in CBTL also includes 1200×10^4t of naphtha;therefore,the total amount of naphtha produced can reach 1.20×10^8t. In the coal chemical sector,the MTO/MTP process can also produce a certain amount of olefin to meet the basic demand for organic chemical materials.Only by means of the collaboration between all sectors involved ,can the low-carbon scenarios A or B be possibly achieved and the noncooperation by any sector may undermine the achievement of national carbon emission reduction objectives.