Kubratovo Methane Capture & CHP Generation, Bulgaria

The Kubratovo project captures methane from Sofia’s central wastewater treatment plant and converts it into electricity and heat through high-efficiency CHP units. This replaces grid electricity and on-site diesel, sharply reducing direct methane losses and lowering operational emissions. The upgrade shifts sludge treatment from open, low-tech processes to enclosed digestion aligned with EU best practice.

Under Gold Standard ID 4238, the project delivers about 61,700 verified emission reductions each year. Certified impacts include cleaner water systems, more resilient urban services, and significant climate benefits through avoided methane release and fossil fuel displacement. Excess electricity fed to the grid further amplifies the climate value.

Developed by Sofiyska voda AD, the installation modernises the plant with four digesters, a full gas-handling system, emergency flaring, and CHP engines. The result is stabilised, pathogen-free sludge, reduced odour, lower landfill dependence, and a sustained stream of high-quality VERs available to buyers seeking documented, infrastructure-linked climate mitigation.