Parabolic Solar Cooker Cooking: Heat Pipes or Spiral Copper Tubes
Abstract
The idea of cooking with the sun is not new and most recently solar energy has been identified by many researchers as a solution to the challenges of poverty and hunger in the world. Solar coking is believed to be a contributor to the fight for the elimination of insufficient and or expensive energy supply for homes and industrial cooking. The parabolic types of solar cookers have been identified to cook faster at high temperatures and when they are used indirectly with the cooking section separated from the dish, they often abolish the exposure of the user to the sun and can thus be incorporated to kitchen designs. Despite this breakthrough, indirect parabolic cookers still faces a major problem, which is identifying the right cooking section type as most of the ones in existence often achieve a low utilisation efficiency as compared to their potentials. In order to analyse and predict the best cooking section type for parabolic cookers an experimental cooking was performed at Stellenbosch University, South Africa using two different types of cooker sections, the first being using coiled spiral copper tube and the other using heat pipes of 2 l volume. The cooking section was separated from the dish and was not exposed to the sun, the working fluid was transferred using high temperature flexible hose. Both types of cookers were found to be effective with the heat pipes boiling water in a record time but no heat control; the spiral copper tube also reached boiled water although at a little longer time but the flow of heat to it could be regulated. Both were seen to have their advantages and disadvantages and the selection would be based on the desired use of the cooker by the manufacturer, but base on cost, the use of spiral copper tube is recommended in this report.
Keywords
Parabolic solar cookers, Heat pipes, Spiral copper tube