Circulation Pump Power for Solar Water Heater

By Joseph Nowarski

Subjects: SWH, Pump Power, Solar Pump, economic evaluation, solar law, Solar Water Heater, sustainable development, energy balance, solar legislation, green development, solar optimization, Pump Energy Consumption, optimization, water heater, solar heater optimization, building standards, energy conservation, specific conductivity, thermal resistance, Circulation Pump, water heating, SDWH, thermal insulation, energy simulation, building energy, solar radiation, solar energy, renewable energy, Pump Efficiency, green buildings, Forced Circulation, solar calculations, thermal conduction, analysis

Description: This publication introduces calculations of circulation pump power for solar water heater, forced circulation system. The theoretical power is estimated as 0.5 Watt, while the nominal power of the relevant pump is 6 Watt. Energy consumption of such pump is 25 kWh/year. The required water flow is 2 liters/minute and the pump's head is 1.5 meter. The publication determines, step by step, water flow, pressure drop in solar collector and pipes, and theoretical power of circulation pump. Calculations are for solar water heater for residential unit located 9 floors from the solar collector on building's roof. The size of the solar water heater is 150 liters storage tank and 6,150 kcal/day collector. Excessive power of circulation pump increases water flow and decreases stratification in storage tank with negative impact on solar collector's efficiency and energy losses in circulation pipes. Therefore the power and specifications of circulation pump must be carefully determined.