Modeling and on-field testing of a Solar Rice Cooker

This paper presents modeling, fabrication and on-field testing of a Solar Rice Cooker (SRC). Modeling includes the development of a theoretical formalism to compute available solar power (qa) from different components of the system; describes suitable component materials and also includes the load dependent performance analysis of the system for rice cooking. Essential constraints on available energy and cooking time for assured cooking and their interrelationship with system parameters have been deduced and discussed at length. Using the solar geometry, the value of qa has been computed theoretically on equinox day. It varies from 82 to 120 W and its average value is about 107.8 W for the duration 10:00 to 15:00 solar time. As per modeling SRC has been fabricated and its on-field testing has been performed on various days under different conditions. The maximum temperature attained by container's top surface is 142 °C. The rice cooking time for first and second meal is found to be 2 h and 2 h 20 min, respectively. The payback period and NPV (net present value) have also been computed for SRC. With light weight 6 kg, reasonable cost 2500 INR, high NPV and short cooking time SRC is a suitable rice cooking appliance.