Solar panel power ratings aren't calculated at 12V, more like 17V (and at 20C panel temp). Realistic current output would be 12-15 amps, depending on the panel temperature.Quote:
Originally Posted by bacicat
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Solar panel power ratings aren't calculated at 12V, more like 17V (and at 20C panel temp). Realistic current output would be 12-15 amps, depending on the panel temperature.Quote:
Originally Posted by bacicat
at STC which is panel temp, not ambient at 25c. also at perfect azimuth and inclination. keep in mind you will spike with cloud edge effect.Quote:
Originally Posted by bee utey
80w minimum in summer in townsville.
but youo have to do everthing right.
120w is more realistic
I have a 130 watt solar panel fitted to my camper and can run all the leds at night, led floodies, 50 litre waeco, charging tablet, phones etc, running pump for water tank and upstairs power to my rooftop tent from 2 x 100 amp agm batts and never come close to running out, low energy developments on ebay is the dealer of choice and there regulators are very reasonable
cheers
ken
Thank you all for your input
So since posting this topic I have been offered an near new 80w watt camping style panels with all the stuff for $150. And as I am going camping this coming weekend. I did think at the price and size was may be too good to refuse.
But as some have said will help a bit but will invest in a higher one later.
Thanks again
We had an 80 watt panel about 7 years ago, bought it for $900 and sold it for $850 after our trip- they sure have got cheaper since then. We found 80 watt sufficient for 40l fridge and evening lighting. That was in the Kimberley, high ambient temps but also lots of sunlight. Spoke to a bloke at Windjana Gorge who had a 60watt panel and they were finding it insufficient.
Recently bought a 120watt panel, should do it all easier, so much more affordable now.
We have 120w folding panels, Rich Solar brand bought of eBay for $176 delivered, includes regulator. Is fine for our use and keeps the 100ah battery full whilst charging ipad/Nintendo, water pump, etc.
I'll report back on how my system does over the next 4 days - we are heading out tomorrow. Will likely be in the one spot for almost all that time, with a new Fullriver 100Ah battery and a 120w panel running a 38 litre Engel and some LED lighting. Days are getting shorter and the forecast is for cloudy, so I'm not expecting miracles, but it will be a good test for it as the last few times I've been out it has always been sunny all day.
I have 2 68W amorphous panels and they perform well. This is a mppt controller with the panels in full sunshine.
https://www.aulro.com/afvb/images/im...014/04/467.jpg
The reason it reads high is that amorphous panels reduce after the first 6-8 weeks of use so for the first few times you use them you get some good power until they settle in.
These are 2 panels connected in series so higher voltage and less amps which allows thinner wire and longer runs if required. The mppt then reduces voltage and increases the amps to the battery.
The reason I choose amorphous panels is that they lose less the hotter they get than standard solar panels, -0.21% compared to -0.5% for mono cells. Assuming your panels reach 65C in the sun 136W amorphous loses 11.4W, the mono loses 27.2W. There's downsides to amorphous as well, like they are very big.
Saying all that though as long as the beer is cold it doesn't matter, my system worked well over Easter. Full sunshine every day meant the 110AH battery was fully charged by 12-1PM. After that the mppt just cut in when the fridge cycled allowing the panels to run the fridge directly.