Question

Design a 24V standalone DC PV system to power a clinic with DC fridge/freezer combination to store vaccines in addition to light, test equipment with three days of storage. The maximum daily demand of 1000 Wh occurs during summer. Assume the peak sun hour is 5.0. The available NABRA modules have VOC =21.7V, ISC= 6.5A, VMP=17.4V, and IMP = 5.8A at STC. The module de-rating factor is 0.85, wire efficiency is 0.95 and battery charge efficiency is 0.85. Use the Abri 6V, 220Ah deep cycle battery with 0.8 depth of discharge and 0.92 temperature derating.
a) What is the energy (Wh) to be supplied by the modules?
b) How many modules are required in series and parallel?
c) How many batteries are required in series and parallel?

Answer 1