How many \(50 \mathrm{~W}\) panels will the owner require assuming battery storage is \(75 \%\) efficient and all loads are DC (no inverter)?

a. For a stationary system "seeing" \(5 \mathrm{~h}\) of sunlight per day?

b. For a tracking system "seeing" \(8 \mathrm{~h}\) of sunlight per day?

The owner of a small cabin would like to convert her home to PV power. She has the following equipment and associated run times:

Power Run Time Household Equipment (W) (Day) (h) Run Time (Night) (h) Lighting (DC) 25 2 4 Stereo (AC) 40 3 2 Refrigerator (DC) 125 3a Water pump (DC) 400 1.5b 0.5b Alarm clock (DC) 8 12 Computer (AC) 250 3 Printer (AC) 175 0.25 Outdoor safety lights (DC) 48 0 Answering machine (AC) 7 12 Coffee pot (AC) 1200 0.25 2008 20 12 12 a The refrigerator is assumed to run 25% of the time. b It can be assumed that the pump and fan will not start precisely at the same instant. It is assumed that the night- and daylighting loads will not be on simultaneously.