Nano-thermal energy storage system for application in solar cooker

Abstract

Abstract Most of the household relies on an LPG cooking stove for meal preparation, with approximately 20 crore families across India consuming 1.5 lakh crores of LPG annually. Due to their dependency on open areas, present solar cookers are useless at night and morning, restricting usage to the afternoon despite sufficient solar radiation for 9–10 months. Phase-change materials and expensive thermal energy storage (TES) devices are needed for conventional solar thermal power facilities. An economical TES system using parabolic sun dish collectors is needed to decrease LPG import costs and pollution. In response, this project aims to design a solar parabolic dish collector coupled with a TES system, utilizing specially engineered carbon bricks to enhance heat storage and retrieval capacities while reducing initial costs. Employing ANSYS-CFX software, the TES system undergoes thorough examination. Computational fluid dynamics analysis is conducted to evaluate heat transfer coefficients for both the hot fluid, responsible for heating the bricks, and the cold fluid, which cools them. The results reveal heat transfer coefficients ranging from 15 to 20 W/m2 K for the hot fluid and 25 to 40 W/m2 K for the cold fluid, with the latter demonstrating higher coefficients attributed to air’s higher density compared to the hot fluid’s lower density. Overall, the TES system exhibits an estimated heat transfer coefficient of 20–25 W/m2 K, facilitating efficient heating and recovery of heat.