MJLorton Solar Power and Electronic Measurement Equipment Forum

Solar Power => Solar Power => Topic started by: Fuzz on October 23, 2016, 12:37:13 AM

Title: Calculations On Panel Array
Post by: Fuzz on October 23, 2016, 12:37:13 AM
Ok so I've been going through the solar videos on youtube and am currently trying to figure out the size of my panel array, after some confirmation /thoughts on this.

I'm using the following information, average usage per day is 30kwh, I live in Brisbane Australia (Redland Bay) which according to the solar radiation data my region experiences 4.6kwh per day on average across the year, calculating approx 50% loss on the system as I want to run battery storage.

According to my notes from the vids:

Solar Array Size = (wh required/loss)/solar radiation of your area)
x = (30000/0.5)/4.6
x = 60000/4.6
x= 13045wh

I'm not actually using 30kwh/day at present, I'm using on average 24kwh/day however I'm building a home that will have a large pool and air conditioning added on top of what we currently are using hence the assumption of 30kwh/day.

This seems to be telling me that I need a 6.5 or 7kw system? Is this correct???

I'm sure most of the house systems I've discussed with others are 5kw e.g. 20 x 250w panels run over 6hrs..........I realise they are assuming they will get 6hrs of solar radiation which doesn't seem to be the case according to the data for my area, and they are not allowing for loss on their system, they are probably just considering a straight solar array and grid tie inverter setup.

This data would suggest I'm going to need 28 panels @ 250w, is this about right?