Experimental analysis of an institutional solar PV-powered steam cooker with sand-based thermal energy storage

Access to clean cooking solutions is a significant issue in most developing countries, where traditional biomass dominates the cooking sector, contributing to indoor and outdoor air pollution. This study has developed an institutional solar PV electric steam cooker (ISESC) that integrates sand-based thermal energy storage (TES) as a sustainable option for large-scale cooking. The ISESC converts solar PV electricity into thermal energy stored in the mine’s sand, generating steam for cooking. Various solar radiation conditions (400-900 W/m²The ISESC achieved a thermal efficiency of 38.9%, surpassing Schaeffler dish-type solar steam systems (25-26.5%) by about 12-14% at comparable load conditions. The ISESC was able to cook rice, beans, and bananas with a final chamber temperature of 105–110 °C, confirming the system’s capability for institutional-scale cooking. Lifecycle cost analysis showed that despite greater upfront investment, ISESC achieves payback in 4.5 years and reduces total 20-year cooking costs by approximately 47% compared to conventional biomass cookstoves. ISESC emissions savings include 5312 kg of carbon dioxide, 11 kg of nitrogen oxides and 7 kg of particulate matter 2.5 annually, directly contributing to Sustainable Development Goals 7, 13 and 3. The originality of this work lies in integrating sand-based TES with steam cooking at the institutional level, providing an exemplary pathway for the transition to sustainable, efficient and clean cooking in sub-Saharan Africa.