Congrats! Glad to have another solar roof in the "neighborhood".
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Post Your Tesla Solar Layout
- Thread starter pdx_m3s
- Start date
Congrats! Glad to have another solar roof in the "neighborhood".
Thanks! I've heard there are actually another 3 or 4 litterally within my Chantilly neighborhood, but I haven't seen or found them yet. Good to hear there is at least 1 confirmed nearby. Hope it has been treating you well!
So far, so good. In case you are interested, here's a (little too long) time lapse video of my install:
and to stay on theme with this thread, my layout is here.
That's a lot of roof penetrations! I would definitely try to move some to be SW-facing if you can.
Also, I would go as big as your utility and wallet would allow. Will 24 panels fully offset your usage?
There's not that many, probably interpreted stain marks from the satellite images as penetrations.
It will cover ~133% of our day time usage. Night time rates are really low here due to wind, and can even go negative many nights including last night ($/MW)
In that case, I would try to send them photos to get the layout cleaned up. Maybe I'm just a little particular, but a disjointed layout like that would grind my gears if there were no actual roof penetrations to work around.
Is moving the vents difficult? Expensive? Requires engineering, or just a plumber?
Depends on what the vents are for, but a roofer should be able to do it. Just call around.
Here's my proposed layout (north is up). Tesla says the estimated year 1 production is 9110 kWh I'm concerned with having panels facing in three different directions. I assume I'll get the Tesla inverter - does "four maximum power point trackers" mean that it can handle this well? Is 9110 kWh low for 24 panels?
As long as east/west/south are each on their own MPPT string, then there's no issue. What I'm not sure of, though, is what the minimum string length is (# of panels), as you only have 6 panels facing south. I believe for SE inverters, the minimum string length is ~8 panels.
Well, I guess my assumption was that each MPPT channel needs it's own "string," but perhaps that's not the case. Maybe there is not a minimum MPPT channel length? It would be worth doing some more research on.
nwdiver
Well-Known Member
Yes to both. The amount of light hitting a panel is proportional to the current the panel produces and the temperature of the panel is proportional to the voltage. Current has to be equal through all panels in a string so if two panels face a different direction their MPP current will be different. The minimum voltage for the Tesla inverters is 100v IIRC so you probably need at least 3-4 panels to reach that minimum.
There's no need to be concerned. By facing different directions, they can put more panels on your roof and better optimize the inverter. Our solar system has 5 arrays facing 4 different directions at 3 different angles. This takes advantage of nearly every spot possible on our roof and allows us to have good production throughout the day and throughout the year. If we'd limited the panels to only face one direction, our system would be 43% smaller.
Thanks for the clarification. So in the poster's layout, each orientation (east, west, and south) would get it's own MPPT channel. Or perhaps each roof plane would get its own (the poster has 2 west-facing planes).
nwdiver
Well-Known Member
Each orientation should have an independent MPPT. If the amount of sunlight received could be different it should be on a different channel.
Thanks. I'll make sure this is how they set it up (site survey is next week). And in fact, since there should be 4 MPPTs available, I'll ask for the two west facing to be on different ones, since there's a large tree in the front yard that will shade the group of 6 at certain times of the day (and even more so in low sun angle times of the year).
nwdiver
Well-Known Member
Shade isn't that big of a deal. In fact a single MPPT could actually be better. Sections of a panel that are in shade get 'deleted' electrically via bypass diodes in the panel. If you have 5 panels on a MPP channel and 3 are in shade you effectively kill that string since 2 panels won't be enough to get to the 100v minimum. BUT... if you have 10 panels on a MPP and 3 are in shade the other 7 can keep producing just fine.
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