从燃煤热电联产到天然气冷热电联供——中国工业和建筑物从一次能源到终端利用模式的战略转型

From Coal-Fired CHP to Natural Gas-Fired DES/CCHP——The Strategic Transformation of Primary Energy Use and End Use Models in China′s Industrial Sector and Buildings

燃煤热电联产(CHP)与天然气冷热电联供(DES/CCHP)是非常重要的能源系统技术。CHP着眼于一次能源转换效率的提高,但能采用CHP的工业有限,而建筑物用能中也只有冷季节的供暖,加之碳减排的压力,进一步压缩了燃煤CHP的发展空间。天然气的快速发展和科技进步催生了DES/CCHP技术,它以"高能高用、低能低用,温度对口、梯级利用"理论指导能源领域全过程的系统优化、能效提高,目标是高能效、经济性和碳减排。中国发展燃煤CHP和天然气CCHP都比世界迟了几十年,燃煤CHP仍将继续发挥作用,而加快发展天然气CCHP无疑更为重要。"十二五"期间新增GDP的相当大一部分是在新开发的工业园区和新城区,如果新区新增1200×108m3/a天然气用量,把发电和供冷、热、汽集成在一起,建设几百个百兆瓦级的区域型DES/CCHP,就能替代3×108t标煤/a,可比传统利用途径多替代约1×108t标煤/a。如何付诸实现,首先必须转变观念,要从能源全局和战略高度规划天然气CCHP;其次有关部门应尽快把提高能效、碳减排和碳排放份额指标分解落实到位;还要制定各种政策、法规给予支持。

Coal-fired combined heat and power（CHP） generation and natural gas-fired distributed energy system combined cooling,heating,and power （DES/CCHP）generation are important energy system technologies.CHP focuses on raising the efficiency of conversion of primary energy,but only a few industrial sectors are able to adopt CHP.In addition,as buildings need heating only in cold months,plus the pressure on carbon emission reduction,the room for further development of coal-fired CHP has been further compressed.The rapid growth of the natural gas industry and technological advancement have midwifed the development of DES/CCHP technology,which guides system-wide optimization and energy efficiency improvement for energy use based on the theories of ＂High Energy for High-End Use,Low Energy for Low-End Use,Temperature Matchup and Cascade Utilization＂ , aimed at high energy and economic efficiency and carbon emission reduction.China is decades later than developed countries in developing coal-fired CHP and CCHP.Coal-fired CHP will continue to play a role in the country and accelerating the development of CCHP is no doubt more important for China.A large portion of the GDP addition during the Twelfth Five Year Plan period will come from new industrial parks and new urban areas.If these new areas increase natural gas consumption by 1200×10^8m^3/a to establish hundreds of regional DES/CCHP systems with generating capacity exceeding 100 megawatts by integrating power generation,cooling,heating and steam supply,3×10^8t of coal equivalent of coal could be replaced annually,about 1×10^8t of coal equivalent per year more than the amount of coal replaced by traditional means.To bring the above assumptions into practice,first of all,we must change our concept and plan CCHP in the big picture of energy use and from a strategic perspective.Regulators should allocate the specific tasks for raising energy efficiency and reducing carbon emissions and quotas for carbon emissions as soon as possible and come up with various policies and regulations to support the implementation of these tasks and quotas.