Solar-Powered Biomass Revalorization for Pet Food and Compost: A Campus-Scale Eco-Circular System Based on Energy Performance Contracting

The integration of renewable energy and biomass valorization is essential for developing circular and climate-resilient energy systems, especially within institutional settings. This study introduces a novel campus-based model implemented at Alanya Alaaddin Keykubat University (ALKU), where post-consumer food waste from 30 different cafeteria menus is converted into value-added products—pet food and compost—via a 150-liter ECOAIR-150 processing unit powered entirely by a 1.7 MW rooftop photovoltaic system. The solar energy infrastructure was established through Türkiye's first public-sector Energy Performance Contract (EPC), enabling zero electricity cost operations. Monthly averages show the conversion of 260 kg of organic waste into approximately 180 kg of pet food and 50 kg of compost, with a measured energy consumption of 1.6 kWh per hour and an average conversion efficiency of 68.4%. The system contributes to an annual reduction of approximately 17.5 tons of CO₂ emissions. Economic evaluation estimates a monthly gain of 55–65 USD, resulting in a projected payback period of 42 months. In contrast to reviewed literature, this study uniquely combines EPC financing, renewable energy integration, and waste-to-product transformation in a replicable academic environment. The findings offer a scalable framework for sustainable campus operations aligned with the UN Sustainable Development Goals.