Soldato
Thats if they supply 435 panels……distance on maps says this
So by the sounds of it im going to have trouble getting even a 4kw system up there
435w panels are 1,722mm long
Solar panels and battery - any real world reccomendations?
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Associate
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same dimensions as the 395w canadian solar they originally quoted, looking to spend ~15 grand and cant get nobody to take accurate measurements lol, its a joke.
Soldato
I measured my own house and then contacted suppliers and told them what i wanted. You just need to measure the house yourself.
You said its 20ft long……so in that case with 5ft panels, you cant even fit 4 on landscape mode. Its 3 max…..so that will 2 rows of 3, so 6 panels. My house was a tad over 8mtrs long, so we fitted 2 rows of 4, making a 3.2kw system.
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If landscape would I not get 3 rows of 3? Assuming I cant have 2 rows.
Man, ive gone from possibly 12 to 10 now down to 6. Probably better off getting a building at back of garden beefed up with solar panels lol
Soldato
A lot of solar panels are 1722 x 1134, and you have a 20mm gap for the mounting clamps, these top out at 425w per panel.
So to fit an array of 3 x 2 in landscape you need a space of 5.2 by 2.29 meters plus 0.3 for a border either side taking you to a total width of 5.8 meters, so your house being 20 feet wide is 6.096 meters.
I think you should be able to fit a 3 x 3 array in landscape going by the 3.66 meters shown in your Google aerial view. 3 x 3 would be 5.2 x 3.44 meters of panels, which at 425w per panel is an array of 3.825kW, but htis does depend on the actual roof size, and how much the installer allows top and bottom of the panels.
The bigger panels are 2279 x 1134, so three in landscape would be 6.8 meters.
Whenever I've seen a normal terrace house with solar, they only ever squeezed on small arrays, you need a lot of roof space for powerful arrays.
So to fit an array of 3 x 2 in landscape you need a space of 5.2 by 2.29 meters plus 0.3 for a border either side taking you to a total width of 5.8 meters, so your house being 20 feet wide is 6.096 meters.
I think you should be able to fit a 3 x 3 array in landscape going by the 3.66 meters shown in your Google aerial view. 3 x 3 would be 5.2 x 3.44 meters of panels, which at 425w per panel is an array of 3.825kW, but htis does depend on the actual roof size, and how much the installer allows top and bottom of the panels.
The bigger panels are 2279 x 1134, so three in landscape would be 6.8 meters.
Whenever I've seen a normal terrace house with solar, they only ever squeezed on small arrays, you need a lot of roof space for powerful arrays.
Soldato
My installer said there had to be 300mm clearance top and bottom.....so if thats the case he couldnt fit a 3x3 array as that would be 3.44mtrs + 60cms ( for clearence) = 4.04mtrs
Soldato
my installer said just the bottom and sides had to be 20cm. Pretty sure uk BR say 20cm too, but unsure on MSC guidance.
Soldato
also the peak, due to wind coming over the top and possibly catching the panels......
Soldato
I know, but your not allowing for the actual length of the roof from top to bottom, his measurement was on Google maps which was the distance from the ridge to the edge of the building in a horizontal plane, the roof slopes so it will actually be longer, hence why I said what I've quoted below. Some installers insist on 300mm, some much less, the ones on my house are less than 300, possibly less than 200.
PS The wind comes over the ridge and creates a low pressure area, which can cause panels to lift due to a higher pressure underneath, in much the same way as the wing on a plane generated lift, rather than the wind blowing under the panels and causing lift.
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Man of Honour
Thats super frustrating & feels like they are just swapping bits out to see if it fixes it - chances are solarEdge need to do some software work to get it working properly (or it'll be a 2nd gen BMS)
Soldato
Indeed.
I think its highlighted that 1) the installer do not have the technical expertise/equipment to fault find, and 2) the manufacturer doesn't have good enough UK support. I kind of already knew 2 since its obvious on twitter.
TBH if they would just swap stuff out until everything had been replaced I would be happy! As of now they haven't swapped anything, just sent the spark to check it.
Although getting to the point they agreed there was actually an issue has been a hard fought battle!
Checking it was "just" taking voltage readings from batteries etc and that was IMO never going to detect the fault since its not a level of failure that would suggest a completely screwed pack.
9kwh when its supposed to be 11kwh useable means one pack cannot be completely dead. Although its possible, because the 9 is roughly 9.2 from what I can tell and whilst its a little high its just about possible the difference between a 3 pack system (8.4 useable) and what its drawing is conversion loss.
I am waiting on the other systems review they are doing. I have also gone back and said ok on BMS after this review if the other systems seem ok.
I also asked could I maybe make the changes to batteries on a daily basis to do some testing. They seem to be very much plug and play so waiting to see what they come back with.
I know they need to be balanced, but with weather as it is now its pretty easy to have the batteries at 100%. Especially if I was to for example test 2 day 1 and 2 day 2.
The main issue I have is that I am towards the edge of their install patch so they are not regularly in the area. So cannot just drop in each day to tweak the config for testing.
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lol just thought of a good way to get measurement of roof, ball+string over roof and tie up AFTER throwing the other end to the start of a tape measure and just pull it up and then whip out some binoculars 
Soldato
count the tiles going up the roof line to the peak, then find out what length yuor tiles are and add them up....say tiles are 400mm, 50/50 overlap so thats 200mm, say its 30 tiles high, then you got 30 x 200mm. job donelol just thought of a good way to get measurement of roof, ball+string over roof and tie up AFTER throwing the other end to the start of a tape measure and just pull it up and then whip out some binoculars
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I know there are 12 rows but width size and overlap no idea without taking one off completely, but dad has some paint downstairs so I could alternate color string in 1m intervals but it won't be as exact as a tape measure.
Roof has not been touched since house was built.
Soldato
But you know what type of tiles you have….can look on the internet for sizes
Soldato
No way of knowing what the overlap is from the ground, very unlikely 50%, more likely 30%, but it will vary, different pitches need different overlaps, roofer may have stretched them out a bit more etc.
Just looking more into this, I presume most setups have a setting whereby if you're on a cheap overnight EV rate you can charge the EV and Battery from the grid at the same time and not just have what's in the battery go straight into the EV, if that makes sense ?
Soldato
Yeah. If battery is charging from the grid it can’t discharge into the home. Can also stop the battery discharging at certain times if you like.
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They got the images mixed up I think but has anybody tried these?
Soldato
I have seen them on a roof at a distance, you can also get metal frames that use ballast such as paving slabs or concrete blocks to hold them down. You need to make sure you have enough weight there, and most importantly you're roof is strong enough to hold the additional weight, not forgetting it sometime snows in the winter. When I did my garage I did some calculations and decided the roof wasn't strong enough.