Question

How to Design Solar PV System Exercise: An office unit has the following electrical appliance usage: • Ten 3 Watts LED lights with electronic ballast used 8 hours per day. • Four 20 Watts fan used for 4 hours per day. • One 100 Watts refrigerator that runs 24 hours per day with compressor run 12 hours and off 12 hours. • Two 150 watts air conditions runs 4 hours per day. The system will be powered by 36 Vdc, 250 Wp PV module. 1. Determine power consumption demands Total appliance use = = Total PV panels energy needed = =. 2. Size the PV panel 2.1 Total Wp of PV panel capacity needed = = 2.2 Number of PV panels needed = = Actual requirement = -------- modules So this system should be powered by at least ------ modules of 250 Wp PV module. 3. Inverter sizing Total Watt of all appliances = For safety, the inverter should be considered 25-30% bigger size. The inverter size should be about ---------- or greater. 4. Battery sizing Total appliances use = Nominal battery voltage = Days of autonomy = 1 days Battery capacity = Total Ampere-hours required ____________. So the battery should be rated __________________ for 1 day autonomy. 5. Solar charge controller sizing PV module specification Pm = 250 Wp Vm = 36 Vdc Im = 6.95 A Voc = 43.78 A Isc = 7.20 A Solar charge controller rating = (4 strings x ______ A) x 1.3 _____= ______ A So the solar charge controller should be rated ______ A at 36 V or greater.

Answer 1