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Thats the HWS (north) and the east array of panels, west is identical on the other side
The day we checked the power made, we made 9kwhr, where the north only array (identical panels/inverter etc) made only 8kwhr, that was on an overcast day mind you
Havent been home and done a comparison on a sunny day, I was actually surprised we got that much on a continuous cloud cover all day, but a sunny day all day in winter was still up over 21kwhr, and in summer was over 35kwhr, so there is a major drop off in winter obviously
Madness
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Joined: 08/10/2011 Location: AustraliaPosts: 2498
Posted: 12:31pm 02 Jul 2018
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Cloudy weather is very variable, but white clouds can have a minimal effect sometimes. I have some panels setup temporarily on the ground, now the sun is at its lowest those 3KW of panels make 1-2 hundred watts on a sunny day with partial shade. When it is cloudy they make a lot more power, it is not the ideal setup but don't have anywhere else I can put them ATM.
Mark we can pick the Victorian tourists a mile off here, they are the ones getting around in shorts in the middle of our winter.There are only 10 types of people in the world: those who understand binary, and those who don't.
George65 Guru
Joined: 18/09/2017 Location: AustraliaPosts: 308
Posted: 02:01pm 02 Jul 2018
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The right level of cloud gives my panels better output than a clear day. Might sound like BS but I have seen it a number of times now. I think it is called cloud edge effect but I am often surprised when I think it's been a Little cloudy/ overcast that the generation for the day is very good or even above what it's been on clear days.
I do get peeved on the very overcast days when it does not rain. I can use the water, I can use the sun but those days when I get nothing are annoying!
renewableMark
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Joined: 09/12/2017 Location: AustraliaPosts: 1678
Posted: 09:36pm 02 Jul 2018
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You know how to tell a Queenslander in the snowfields? .........you can't.Cheers Caveman Mark Off grid eastern Melb
Madness
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Joined: 08/10/2011 Location: AustraliaPosts: 2498
Posted: 09:43pm 02 Jul 2018
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Whats snow?There are only 10 types of people in the world: those who understand binary, and those who don't.
Warpspeed Guru
Joined: 09/08/2007 Location: AustraliaPosts: 4406
Posted: 10:11pm 02 Jul 2018
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Its not just the total daily power, but east west will give you power for at least two hours longer per day than north facing panels.
For grid tie, or if running without a battery (as I am) that can make a very big difference. Its probably less important with a really large battery that can actually use a massive mid day peak.
When the weather really sucks, and its all grey and awful, any direction works as well as any other, although straight up is slightly better.Cheers, Tony.
Boppa Guru
Joined: 08/11/2016 Location: AustraliaPosts: 814
Posted: 10:56pm 02 Jul 2018
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I would say its well over two hours in summer, we are still hitting over a kw at 8am, and it remains over 1kw until about 3pm- hitting peak of about 4.8kw about 10 and staying there until after 1pm The neighbours system gets to a kw about 10, hits its peak (about 5.3) about 11, and starts dropping off about 12.30 so his peak is very short in comparison, although a bit higher (both are nominal 6.2kw of panels)
When I get home, I'll get some readings on an allday sunny day (if such an animal happens lol), but in overcast the split definitely seems to have the edge over the northers, esp in daily kwhr totals (according to the inverters panel at least)
Warpspeed Guru
Joined: 09/08/2007 Location: AustraliaPosts: 4406
Posted: 11:11pm 02 Jul 2018
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A lot depends on location.
I am in the suburbs with many large trees and two story houses around. The sun may have risen, but my panels can still be shaded for up to an hour after official sunrise where I am. It varies as the point of sunrise changes, different objects get in the way at different times of the year.
I can well believe more than two hours in a more favorable location with a clear horizon.
Thinking about it, height and a clear shot at the horizon may be more important to get the most advantage out of east/west.Edited by Warpspeed 2018-07-04Cheers, Tony.
renewableMark
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Joined: 09/12/2017 Location: AustraliaPosts: 1678
Posted: 11:25pm 02 Jul 2018
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I get perfectly clear east west in summer, but since it's turned to winter the west cops a bit of a shadow from about 4.00pm, which wouldn't produce much after that anyway. But my bigger east roof with 4500w is totally clear all year round.Edited by renewableMark 2018-07-04Cheers Caveman Mark Off grid eastern Melb
Warpspeed Guru
Joined: 09/08/2007 Location: AustraliaPosts: 4406
Posted: 11:28pm 02 Jul 2018
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That is excellent, because summer is when the sun rises much further south than due east west. Cheers, Tony.
Boppa Guru
Joined: 08/11/2016 Location: AustraliaPosts: 814
Posted: 11:51pm 02 Jul 2018
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Um back to front there Warpspeed, at least for us Ozzies summer is almost directly east west, with high overhead sun Winter is ne/nw with low sun angle (close to horizon)
This all depends on your latitude of course, further south you go, the further north your sun arc goes (and angle above horizon drops also further south you go)
Boppa Guru
Joined: 08/11/2016 Location: AustraliaPosts: 814
Posted: 11:53pm 02 Jul 2018
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And for the real northerners amongst us in Ozzieland (north of tropic of capricorn) I suspect that an east west split would really be the only option, or laying the panels almost flat LOL
Madness
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Joined: 08/10/2011 Location: AustraliaPosts: 2498
Posted: 11:59pm 02 Jul 2018
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It moves towards the north in winter and in summer more southerly, here in mid-summer it rises and sets well south of the east-west line. Someone I know had his panels up at the optimum angle for winter, in summer the sun was shining on the back of the panels early in the morning and late in the afternoon.
An app I find very useful for looking at the suns position at given dates and times is Google Sky Maps. You hold your phone up to the sky and it will identify what is there, it's time travel function lets you put in a date and time and fast forward so you can track the suns path across the sky at any location and any time.There are only 10 types of people in the world: those who understand binary, and those who don't.
Madness
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Joined: 08/10/2011 Location: AustraliaPosts: 2498
Posted: 12:04am 03 Jul 2018
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Flat panels work well in cloudy weather when you need the most power. I would also like to have panels facing east as well but where I am ATM we don't get full sun till after 8:30 AM due to trees. East facing panels would get more significant power early on which would help with the morning peak we have of washing clothes, breakfast and showers.There are only 10 types of people in the world: those who understand binary, and those who don't.
Boppa Guru
Joined: 08/11/2016 Location: AustraliaPosts: 814
Posted: 12:12am 03 Jul 2018
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I found that flat panels work better in cloudy weather myself with the old exploders solar panels. Luckily my sisters place has pretty much unobstructed views in all directions- she's pretty much at the top of a hill on the north side, standing on the roof you can pretty much see the horizon in all directions except south and s/w, although you wouldnt suspect so from ground level with hedges and tall fences obstructing your view
Warpspeed Guru
Joined: 09/08/2007 Location: AustraliaPosts: 4406
Posted: 12:44am 03 Jul 2018
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Definitely flat panels in cloudy weather and the polycrystalines seem to work better than monocrystaline panels in total cloud cover.
The monos seem to work better in clear sun.Edited by Warpspeed 2018-07-04Cheers, Tony.
Boppa Guru
Joined: 08/11/2016 Location: AustraliaPosts: 814
Posted: 09:33am 24 Oct 2018
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Just for interest, we got the elec bill today, last year for the same period was $368.23, for this year it was $155.53 This was despite this year having a 'pet heating pad'(30w) basically on 24/7 for most of the winter months (elderly cat with severe arthritis- Drewie loves her 'blanky' and basically lived on it for the entire winter) Definitely made a difference