With the roar of generators coming to life, a steady stream of landfill gas is being transformed into clean, green electricity—now powering thousands of homes through the local grid. The recent successful grid connection of the Xiaojianxi Biogas Power Generation and Energy-Saving Retrofit Project, developed by the Solid Waste Leachate Company under Qingdao Water Group, marks a significant milestone in the park's efforts to maximize integrated energy use.
Located in the Xiaojianxi Municipal Solid Waste Integrated Treatment Park in Chengyang District, this small-scale power plant addresses long-standing challenges in dealing with low-calorific landfill gas and odorous emissions from leachate regulation pools. Covering an area of 6.86 acres and backed by a total investment of 24.97 million yuan, the project features systems for biogas storage and purification, power generation, selective catalytic reduction, waste heat recovery, and grid connection. Once operating at full capacity, the facility is expected to generate 15 million kilowatt-hours of electricity annually.
Biogas—naturally produced during the decomposition of waste—holds considerable energy potential. Yet managing exhaust gases from municipal solid waste has long posed technical and environmental challenges. At the now-closed Xiaojianxi landfill site, the gas produced is low in calorific value and complex in composition. Meanwhile, leachate regulation pools emit highly odorous gases, rich in hydrogen sulfide and prone to large fluctuations. Traditionally, these waste gases have offered little value and been costly to treat. Converting them into renewable energy has become a key goal for the Qingdao Water Group Solid Waste Leachate Company.
According to the project lead, the retrofit takes an innovative approach by blending high-quality biogas—generated via anaerobic digestion of leachate—with landfill gas and odorous emissions to fuel a unified power generation system. The entire process is fully enclosed to prevent leakage, and the facility is capable of treating up to 7.1 million cubic meters of waste gas annually. The project follows a “self-use with surplus fed to the grid” model. It ensures a stable power supply for the park's leachate and concentrate treatment systems, while excess electricity is transmitted to the national grid—meeting energy demands, reducing operational costs, and generating economic returns. In addition, the waste heat recovery system produces steam that can be sold externally, further boosting energy efficiency and cascading use. This initiative not only improves environmental conditions within the park, but also promotes green economic development and contributes to optimizing the regional energy mix.
In recent years, Qingdao Water Group Solid Waste Leachate Company has actively embraced modern treatment approaches guided by ecological priorities and sustainability goals, accelerating the transition to a new energy system. The successful commissioning and grid integration of the biogas power generation project represent a significant step toward clean energy advancement. Looking ahead, the company plans to ensure the project's stable operation while expanding into reclaimed wastewater reuse, efficient use of hot water and steam, and unlocking the energy potential of sludge—injecting fresh momentum into the region's sustainable economic and social development.
