Natural Gas in Megacities of China A megacity is usually defined as a metropolitan area with a total population in excess of ten million people. It can be a single metropolitan area or two or more metropolitan areas that converge. According to National Bureau of Statistics of the People’s Republic of China data, by the end of 2014, population of Beijing, Tianjin, Shijiazhuang, Shanghai, Chongqing, Chengdu are all over ten million. Among these cities, Beijing, Tianjin, Shijiazhuang constitute Beijing-Tianjin-Hebei economy cooperation region which becomes a hot spot area in recent years. In 2015, residential and electric power gas consumption increased rapidly which drove China total gas consumption growth. Residential, industry, electric power and chemical sectors gas consumption accounted for 39.7%, 30.2%, 15.4% and 14.8% of total gas consumption respectively. Natural gas use increases in residential and electric power gas consumption sectors，whereas declines in industry and chemical sectors than that of previous year. Take Beijing-Tianjin-Hebei economy cooperation region as example, motivated by environment protection policy for air quality improvement, this region change fule of industrial heating boilers from coal to gas. Now Beijing central downtown nearly realizes non-coal heating, gas heating ratio increases from 50% to 80%. Tianjin and Hebei also accelerate coal to gas heating modification projects which stimulate natural gas demand of these megacities. In 2014, Beijing consumed natural gas 11.37 Bcm, Tianjin consumed 4.549 Bcm, Shanghai consumed 7.423 Bcm, Chongqing consumed 8.215 Bcm. Beijing took up 6.2% of China total gas consumption which beyond gas use of most provinces. Share of gas consumption in primary energy mix of Beijing, Tianjin, Shanghai and Chongqing are 25%、8%、9%、15% which all higher than national average level 5%. That means there are great potential for gas use in megacity. Example—Beijing City Natural gas first introduced into Beijing in 1985, but due to the limited supply of gas resources, until 1996, the annual consumption of natural gas in this city is only 130 million cubic meters, only accounted 1% in the proportion of the energy mix. Beijing large-scale use of natural gas began in 1998 Shanxi-Beijing pipeline put into operation, and in the past 15 years, natural gas consumption of Beijing increased by more than 10 times (Fig 1) , and 14.6 Bcm, the proportion of natural gas in the energy consumption structure has reached 22%, far higher than the national average of 6%, and close to the global average of 24%. At present, Beijing's natural gas consumption is the third largest city in the world after Moscow and New York. 20 15 15 11 10 9 10 7 7 6 Bcm 5 5 3 3 1 2 2 2 0 natural gas consumption, gas natural Fig1 2000-2015 natural gas consumption of Beijing From 1997 to 2015, Beijing received 86.8 Bcm of natural gas, replacing 1.37 tons of coal, the cumulative reduction in carbon dioxide emissions is about 65.6 million tons, Beijing blue sky days increased by 60% in 10 years. According to the Beijing Gas, by 2020, Beijing natural gas consumption will be more than 18 Bcm, the gas proportion in energy structure will reach 32%. By then, Beijing will become the world's second largest natural gas consumption city in the world. .