Cooking at low temperatures: energy and time requirements

A flat plate solar collector can easily supply hot water at temperatures upto 90–95°C. At these temperatures, rice, potatoes and vegetables can be cooked without much difficulty. However, to design an efficient solar system for cooking, one must know the exact energy and time required for cooking at these temperatures. Our experiments show that the actual energy consumed in cooking rice, potatoes or green vegetables is only 0.06 to 0.10 kWh/kg at cooking temperatures of 82–88°C and the cooking time at these temperatures is 30–45 min.