China has a sludge problem. A big one. Wastewater plants in Chinese cities produce a staggering 40 million tons of this semi-solid slurry each year, enough to fill all of Manhattan with a 19-inch deep sludge lake. However, only one-fifth of China’s sludge is properly treated, while the rest is sent to landfills, incinerators, or illegally dumped. Similarly unsustainable methods are used to dispose of the mountains of solid waste generated by China’s urbanites. Both sludge and solid waste streams are creating significant air, water, and soil pollution, and are a leading source of urban methane emissions—a short-lived climate forcing gas that traps heat more intensely than CO₂. The U.S. EPA estimates that China’s municipal solid waste (MSW) will generate 50 million metric tons of CO₂ equivalent by 2030, about the yearly CO₂ emissions of New York City. In the United States many cities are capturing waste methane to use as a renewable gas for electricity or transport fuel, but China is just beginning tap the potential of waste emissions.

On September 20th, speakers will share stories on urban waste policies, pilots and innovation. Chen Meian will open up discussing the challenges low-carbon cities face in reigning in greenhouse gasses, and how her think tank is creating a platform for innovative, bottom-up, clean energy solutions. One of the most successful sludge-to-energy plants in China is in Xiangyang City in a plant run by Dou Wenlong. Mr. Dou will explain how his company has built partnerships with the local government to turn captured methane into CNG for a local taxi fleet. Liu Jinghao will give an overview of national-level drivers creating opportunities for methane recovery from MSW and sludge in China. Finally, Liu Xiao will tell a story of how one low-carbon city pilot is sparking climate action in the MSW industry.

The speakers are in the United States participating in a technical research exchange sponsored by the Global Methane Initiative.