Improved control strategy for forced flow solar water heating systems

The solar water heating system functioning on a fixed temperature control (FTC) mode, rather than a differential temperature control (DTC) mode (continuous water flow rate), has appreciable advantages for saying parasitic power consumption and reducing the maintenance cost. A computer simulation model, using a numerical analysis method, has been developed to study a forced flow solar water heating system taking into account the realistic conditions of operations. It is noted that the most critical parameter in designing such types of system is the water flow rate. The results are obtained, corresponding to a solar water heating system of 4000 1/day capacity working at an average temperature of 60°C.