(Cross posted on /r/diysolar)
Just thought I'd present my project.
This is in California, Bay Area, on PG&E (boo, hiss).
It's 30x 315w Canadian Solar panels (9.45kW), on Ironridge XR10 rails, with their HUG quickmount feet. I'm using IQ8+ for these panels, in three sets of 10. The Q-cables are center fed, on 8 gauge wire.
Took a lot longer than I expected, but there wasn't any point at which it felt insurmountable.
I got the plans drawn up by a pro, which was money well spent. Honestly, since you're already saving a ton of cash DIYing it, this is a cheap insurance policy to avoid messing up and having to redo work.
I managed to sneak in under the NEM 2.0 deadline, so my math means I don't need to think about batteries, which saved thousands.
If people are interested, I can present the plan pack I had done, but for now, here's the SLD:
I'm on a 100A service, with a 100A house panel, so I needed to add a 200A sub panel inside the garage to fit the solar breaker. In doing so, I ended up replacing the existing aluminum feed to the house panel. It's 1970s vintage structural aluminum wire crap, so it needed to be done (modern aluminum wire isn't the bad stuff that causes fires... this stuff is).
Side note -- my neighbor had some pros come in and do a similar install -- they didn't replace the aluminum wire, and I guess didn't tighten down the lug nut on the main house breaker. When I went to go take a look at their install, I popped open the breaker panel and was greeted by the side of charged wires, and a partially melted 100A breaker.... Not good.
I did all the work myself, so I needed a safe way of getting stuff up on the roof. I made myself a sled out of plywood, and a set of 2x4 rails on which it could ride. I then would put each panel on that, and winch it up with a pulley block.
The worst part of it all was pulling wire through EMT. Real pain in the but, especially routing it through the attic.
This definitely depends on your skill set, but for the most part it was straight-forward.
Things I wish I'd done better:
Some tips:
Bungee cable to stop panel going "bye-bye" when you work on the cabling:
New 200A subpanel, early picture. (Solar panel breaker in the wrong position, doesn't have hold-down yet, doubled-up neutral was relocated, EMT conduits were bonded to ground)
One of the arrays (gap was closed up):
Soladeck roof pentration junction box:
Early pic of the IQ combiner box:
Solar panel sled:
Some other thoughts:
I chose enphase because I literally was against the clock on the plans -- I submitted them the week of the deadline.
If I were to do it now, I might choose something like a Sol-Ark 15K string inverter (or maybe the EG4 setup). I have fairly small amounts of shading at the moment, so the string inverters don't really help me much.
I do like the per-panel monitoring though. I just wish Enphase was a bit more open with their ecosystem.
I also had to sit on the phone for about 2 hours with tech support as they tried to figure out firmware issues. I have to give it to them -- they were available and responsive. So I definitely have to give them props.
Install the CTs. It gives you so much more info. Note: If you're having issues, it may be that you have L1 / L2 swapped on one of the breakers (not just the CT being flipped).
I like the Soladecks, but they're really big and cumbersome. I would probably go with IronRidge's Jaybox. Much easier to install on the roof. Installing the Soladecks wasn't particularly hard, but I was worried I potentially might be screwing something up and compromising the roofing around it somehow.
The Jaybox don't seem to require the same amount of roofing surgery.
So far, no leaks (fingers crossed).
I'm probably at about $17,000 all-in, call it ~$1.8/watt.
But that includes stuff like probably $400 for replacement copper wire more my house panel, an extra sub-panel, etc.
I'm also probably missing a few hundreds bucks of other random Home Depot expenses.
The companies I bought from included:
altE
Greentech Renewables (local, I picked up the rails from there to avoid freight shipping charges)
Signature Solar
Ressupply
All of them were pretty good with shipping etc. No complaints.
In terms of the big ticket items:
IQ8s - $4900
Rails - $800
Feet + rail HW: $1600
City Permit: $550
PGE Permit + submitter person: $300
Panels: $4700
Plans: $250?
Soladecks: $200?
IQ Combiner: $700(?)
Wire, breakers, new panel, conduit, fittings, etc: $1500-2000?
Keep in mind a lot of this stuff was bought a year ago. It's a bit of a game to wait for sales / free shipping. Some places seem to not charge sales tax(!). Others have good prices, but freight charged will kill you.
I would recommend keeping a spreadsheet to figure out the optimal split.
Just thought I'd present my project.
This is in California, Bay Area, on PG&E (boo, hiss).
It's 30x 315w Canadian Solar panels (9.45kW), on Ironridge XR10 rails, with their HUG quickmount feet. I'm using IQ8+ for these panels, in three sets of 10. The Q-cables are center fed, on 8 gauge wire.
Took a lot longer than I expected, but there wasn't any point at which it felt insurmountable.
I got the plans drawn up by a pro, which was money well spent. Honestly, since you're already saving a ton of cash DIYing it, this is a cheap insurance policy to avoid messing up and having to redo work.
I managed to sneak in under the NEM 2.0 deadline, so my math means I don't need to think about batteries, which saved thousands.
If people are interested, I can present the plan pack I had done, but for now, here's the SLD:
I'm on a 100A service, with a 100A house panel, so I needed to add a 200A sub panel inside the garage to fit the solar breaker. In doing so, I ended up replacing the existing aluminum feed to the house panel. It's 1970s vintage structural aluminum wire crap, so it needed to be done (modern aluminum wire isn't the bad stuff that causes fires... this stuff is).
Side note -- my neighbor had some pros come in and do a similar install -- they didn't replace the aluminum wire, and I guess didn't tighten down the lug nut on the main house breaker. When I went to go take a look at their install, I popped open the breaker panel and was greeted by the side of charged wires, and a partially melted 100A breaker.... Not good.
I did all the work myself, so I needed a safe way of getting stuff up on the roof. I made myself a sled out of plywood, and a set of 2x4 rails on which it could ride. I then would put each panel on that, and winch it up with a pulley block.
The worst part of it all was pulling wire through EMT. Real pain in the but, especially routing it through the attic.
This definitely depends on your skill set, but for the most part it was straight-forward.
Things I wish I'd done better:
- Finding the rafters. I used the HUG mounts because they don't have to hit a rafter (if you use all 6 screws), but I'd have preferred if they all hit a rafter anyway.
- Lining up the roof mounts better. I just followed a line of shingles , which worked pretty well. However, there are a couple of mounts that didn't line up perfectly (maybe 1/8" off), and they cause a bit of a bow in the rails. Not visible, and doesn't affect anything, but still.
- Accidently damaged one of my inverters by tripping on it. Cracked the plastic housing / bent the metal bracket. I've sealed it up, and it seems to work, but a bit of a bummer.
- Looking under the panels, I've got some drooping cabling in places. I should correct it...
Some tips:
- Use conduit lube to pull cables through EMT.
- Use a larger conduit than you need. 1" is great.
- Use one of those adjustable bungee cords to hold panels on to the rails. This allows you to fiddle with wires, etc, without worrying about the panel launching itself off the roof.
- Make a sled / pulley system to haul them up on to the roof. Way safer / easier than lugging them up a ladder
- Buy extra structural screws, feet, UFO brackets (if using ironridge). If you mess up, or have to reorganize the layout to work around obstacles, it will be a big pain to have to reorder stuff.
- For the enphase Q-cables, buy extra drops (at least 1x per string). You might want to center-feed them (or maybe not).
Bungee cable to stop panel going "bye-bye" when you work on the cabling:
New 200A subpanel, early picture. (Solar panel breaker in the wrong position, doesn't have hold-down yet, doubled-up neutral was relocated, EMT conduits were bonded to ground)
One of the arrays (gap was closed up):
Soladeck roof pentration junction box:
Early pic of the IQ combiner box:
Solar panel sled:
Some other thoughts:
I chose enphase because I literally was against the clock on the plans -- I submitted them the week of the deadline.
If I were to do it now, I might choose something like a Sol-Ark 15K string inverter (or maybe the EG4 setup). I have fairly small amounts of shading at the moment, so the string inverters don't really help me much.
I do like the per-panel monitoring though. I just wish Enphase was a bit more open with their ecosystem.
I also had to sit on the phone for about 2 hours with tech support as they tried to figure out firmware issues. I have to give it to them -- they were available and responsive. So I definitely have to give them props.
Install the CTs. It gives you so much more info. Note: If you're having issues, it may be that you have L1 / L2 swapped on one of the breakers (not just the CT being flipped).
I like the Soladecks, but they're really big and cumbersome. I would probably go with IronRidge's Jaybox. Much easier to install on the roof. Installing the Soladecks wasn't particularly hard, but I was worried I potentially might be screwing something up and compromising the roofing around it somehow.
The Jaybox don't seem to require the same amount of roofing surgery.
So far, no leaks (fingers crossed).
I'm probably at about $17,000 all-in, call it ~$1.8/watt.
But that includes stuff like probably $400 for replacement copper wire more my house panel, an extra sub-panel, etc.
I'm also probably missing a few hundreds bucks of other random Home Depot expenses.
The companies I bought from included:
altE
Greentech Renewables (local, I picked up the rails from there to avoid freight shipping charges)
Signature Solar
Ressupply
All of them were pretty good with shipping etc. No complaints.
In terms of the big ticket items:
IQ8s - $4900
Rails - $800
Feet + rail HW: $1600
City Permit: $550
PGE Permit + submitter person: $300
Panels: $4700
Plans: $250?
Soladecks: $200?
IQ Combiner: $700(?)
Wire, breakers, new panel, conduit, fittings, etc: $1500-2000?
Keep in mind a lot of this stuff was bought a year ago. It's a bit of a game to wait for sales / free shipping. Some places seem to not charge sales tax(!). Others have good prices, but freight charged will kill you.
I would recommend keeping a spreadsheet to figure out the optimal split.
