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

Abstract

• Hybrid solar PV and thermal energy storage for an institutional e-cooker (ISESC). • The sand-based thermal battery sustained cooking even during low solar radiation periods. • ISESC achieved reliable cooking temperatures between 105-110°C for multiple food types. • Experimental trials prove solar steam cooking feasible for institutional food preparation. Access to clean cooking solutions is a critical issue in most developing countries, where traditional biomass dominates the cooking sector, contributing to indoor and outdoor air pollution. This study developed an institutional solar PV electric steam cooker (ISESC) that integrates sand-based thermal energy storage (TES) as a sustainable alternative for large-scale cooking. The ISESC converts solar PV electricity into thermal energy stored in quarry sand, generating steam for cooking. Field tests were conducted at a senior high school in Ghana to assess the cooking performance of commonly consumed staple foods under varying solar irradiance conditions (400-900 W/m 2 ). The ISESC achieved a thermal efficiency of 38.9%, surpassing Scheffler dish-type solar steam systems (25-26.5%) by roughly 12-14% at comparable load conditions. The ISESC was able to cook rice, beans, and plantain, with final chamber temperatures of 105-110 °C, confirming the system's capacity for institutional-scale cooking. The lifecycle cost analysis revealed that despite a higher upfront investment, the ISESC achieves payback in 4.5 years and reduces total 20-year cooking costs by about 47% compared to traditional biomass cookstoves. The ISESC emission savings include 5312 kg of carbon dioxide, 11 kg of nitrogen oxide, 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 an institutional scale, providing a replicable pathway for sustainable, efficient, and clean cooking transitions across Sub-Saharan Africa.