Design, Fabrication and Thermal Performance Evaluation of a Parabolic Solar Cooker in Sokoto City, Nigeria

This study investigated the design, fabrication and thermal performance of a parabolic solar cooker constructed using locally available materials for application in Sokoto city, Nigeria. The cooker incorporated a parabolic reflector and receiving vessel mounted on a supporting frame at a fixed southward tilt angle of 13°. The fabricated concentrator had an aperture diameter of 77 cm, an estimated focal length of 0.309 m and a geometric concentration ratio of 4.15. Thermal performance was assessed through a water-heating experiment involving 1.0 L of water as well as statistical correlation tests using Analysis of Variance (ANOVA). The water temperature increased from 29.3 °C to 81.4 °C over 150 minutes, corresponding to a calculated useful energy gain of approximately 2.18 × 10⁵ J and average useful thermal power of 24.2 W. A thermal efficiency of approximately 22.7% was estimated using an assumed average solar irradiance of 229.17 W/m² because irradiance was not measured during the experiment. The correlation tests showed statistical significant evidence for a strong relationship amongst the dual-based thermal performance parameters considered at the considered confidence level. The findings demonstrate that the fabricated cooker was capable of heating water under the investigated outdoor conditions. However, the absence of measured solar irradiance, repeated experimental trials and uncertainty analysis limits the reliability of the estimated thermal efficiency. Further evaluation under measured solar conditions and standardised solar-cooker testing procedures is recommended to establish reproducible performance characteristics.