Solar panel production figures

Ron-ski said:
I suspect your roof isn't south facing, as it should get the sun pretty much all-day as it moves from the east to the west.
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It is but it drops off considerably when sun goes round back of house around 5-6pm, south facing pitched roof, after 5:30-6pm no direct sunlight on panels.

EDIT
Closest example I could find for an uninterrupted day, at the end it kinda hangs on 200w til it got low enough to not be picked up by the All-In-One system, back then it didn't show anything below 200w on the graph for some reason.

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Thats just the nature of south facing it should be highest generation but its very peaky in summer.

Compare your graph to my SW system, it ramps up later in the day but lasts longer in the evening so you arent losing hours of sun its just hitting your panels at a different time and your peak is about 2 hours earlier. I had to scroll back a long time to find a good graph :cry:

System is 5kw but you get the idea.

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200sols said:
Thats just the nature of south facing it should be highest generation but its very peaky in summer.

Compare your graph to my SW system, it ramps up later in the day but lasts longer in the evening so you arent losing hours of sun its just hitting your panels at a different time and your peak is about 2 hours earlier. I had to scroll back a long time to find a good graph :cry:

System is 5kw but you get the idea.
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I was more referring to generating sub 700w for 2-3 hours when sun goes behind home as sun isn't hitting the panels, trying to save up to get something sorted in the garden, lot of times its a crappy day the sun comes out when its finally behind house lol
 
Here is what 9 due east and 14 due west 430W panels at 40 degrees look like with no shading in the height of June. Performance was ultimately clipped by heat here as the array can peak at over 8kw which is the maximum of my inverter.

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So I get an extra 2 hours or so of 'proper' generation but overall generate about 30% than their south facing counterparts.

East/West facing panels also get hit hard in the winter when the sun isn't really high enough to hit the panels directly for most of the day. Because of the pitch, I actually see a dip over mid day, that's not ideal when its the peak generation time. My neighbours south facing system which has 12 panels (and some shading) can out generate my 23 panel system when the sun is very low during winter. That's just when you need it the most when you have heat pump!

Hear is a clear (ish) January day:

8ZohqZG.png


Edit: I get a bit of shading in the winter from my L-shaped house, the 9 east panels are 'inside' the L and as the sun moved sound to due south, the south /north pitch shades the east slightly. It wasn't worth putting a south facing panel on, only one would fit!
 
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alphaomega16 said:
I was more referring to generating sub 700w for 2-3 hours when sun goes behind home as sun isn't hitting the panels, trying to save up to get something sorted in the garden, lot of times its a crappy day the sun comes out when its finally behind house lol
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Its all this talk of the sun going behind your house, that made me wonder if your roof really was pointing exactly south.

If the garden only gets sun early evening it probably won't be worth it, but if they'd get a lot of sun in the garden then it would be.

I just look at this and compare to Google maps without rotating the map of course.

The back off my house faces very slightly more SW than SSW, but basically back is SSW, front NNE, which means the other two are WNW and ESE

Compass-Directions.png
 
Terraced housing and just before 6pm is when the sun would be directly on the side of the house.

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The thing top left is old dug out hole in ground used for a pool when we were young that was turned into fish pond.

Not bang on dead center south but close.
 
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Very close indeed, if that's a shed on the right, you could get some panels on that, but the house may shade it, or build a gazebo across the bottom with bifacial panels, tilted west at 10 degree pitch.

Solar stats for the day, very poor, didn't think we'd get the forecasted 30, ended up with 16.77 and 11.8 exported, will have to pay for some electric today!
 
Ron-ski said:
Very close indeed, if that's a shed on the right, you could get some panels on that, but the house may shade it, or build a gazebo across the bottom with bifacial panels, tilted west at 10 degree pitch.

Solar stats for the day, very poor, didn't think we'd get the forecasted 30, ended up with 16.77 and 11.8 exported, will have to pay for some electric today!
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Dads tool shed and mums summer house, don't want to dig onto those. I was hoping to get something built at the back, some kind of storage area (the shed there now just has stuff in it, no roofing and windows are non existent, keep telling dad to take it down) and have panels put on that.

Both sheds are north/south facing though.
 
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Well a poor day only saved by two and a bit hours at tea time taking it from 9 up two 15.60 made today battery's are at 34% after a hammering with the washing and drying today and we just might and its going to be close make it over night with that

House System is East West
down in not so sunny Devon.
East 8 x 420w panels 45 deg pitch
West 10 x 420w panels 45 deg pitch
Givenergy Gen3 5kwh hybrid
2 x 9.5 battery's

Workshop system is South/East
2440w of panels two 720w strings
one 1000w string
Hybrid inverter with 4x 12v 100Amp
Battery's
Plus grid tie inverter as well
 
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