The society officially rolled out its Zero Waste to Landfill project to its 172 food stores last week. Through the project, all food waste is sent to an anaerobic digestion plant, which turns it into renewable energy. Cardboard and plastic are also recycled.
The rollout follows a successful pilot scheme in six food stores last year, which was extended to 60 stores in November.
The pilot project led to Midlands Co-op being shortlisted for Green Retailer of the Year at this week's The Grocer Gold Awards.
"To be able to make such a claim is very exciting for the society," said head of retail trading Michael Spencer. "Not only are the benefits obvious for the environment, the switch has proved better than cost-neutral to the business."