New home owner, existing panel questions, possible upgrade paths.

[FreeMoney]

Hi Solar Gurus,

We purchased a home near Sacremento, CA area which has a Solar grid tied system, moving in early August. From what I can tell, the home has (10) panels on the roof, a Sunpower inverter. Which might be one of the following models:

SPR-4000x 4000w max
SPR-3300 3300w max
SPR-2800 2800w max. (maybe not because of Ppk recorded 3092w?)

I captured late afternoon reading E-day 5.8kWh which is pretty low. I suspect the panels (7 years old) have never been cleaned and might have bird dung all over them.

First question:
The inverter has a Ppk value recorded of 3092W and Ppk-Day of 1136w. The (3092w) tells me that (10) panels were generating about 300w each peak? Would someone estimate what you think the per panel watt ratings might be? (200, 250?).

Second question:

Looking to upgrade. Considering there is a rail for 10 panels, cheapest upgrade might be to drop in (10) 350ish watt panels (if the inverter will support it)? Any suggestions?

Thanks

[SunEagle]

Hi Solar Gurus,

We purchased a home near Sacremento, CA area which has a Solar grid tied system, moving in early August. From what I can tell, the home has (10) panels on the roof, a Sunpower inverter. Which might be one of the following models:

SPR-4000x 4000w max
SPR-3300 3300w max
SPR-2800 2800w max. (maybe not because of Ppk recorded 3092w?)

I captured late afternoon reading E-day 5.8kWh which is pretty low. I suspect the panels (7 years old) have never been cleaned and might have bird dung all over them.

First question:
The inverter has a Ppk value recorded of 3092W and Ppk-Day of 1136w. The (3092w) tells me that (10) panels were generating about 300w each peak? Would someone estimate what you think the per panel watt ratings might be? (200, 250?).

Second question:

Looking to upgrade. Considering there is a rail for 10 panels, cheapest upgrade might be to drop in (10) 350ish watt panels (if the inverter will support it)? Any suggestions?

Thanks

Remember your inverter is the limiting factor to what it will provide to your home. Find out exactly what inverter you have and how much pv wattage it will handle. Then you can start to figure what you can or can't do to upgrade your system.

[FreeMoney]

Remember your inverter is the limiting factor to what it will provide to your home. Find out exactly what inverter you have and how much pv wattage it will handle. Then you can start to figure what you can or can't do to upgrade your system.

Make sense. Any brand suggestions, places to buy, for a 6-7k inverter? Any brands to skip?

I've done my own electric wiring, breaker replacement, 240v outlet setups in past. Any reason why I cant just replace an inverter on my own? (cautious question is all). We live in California but are from the east coast, so don't judge me based on "CA"

[bob-n]

I can't tell you about the regulations in your area, but many places allow non-licensed homeowners to do electrical work themselves. If the power level of the system changes, however, you will require power-company approval and probably also a city/town safety inspection.

As for whether a handy, careful person can do it effectively, yes. You must follow procedures for safety and for quality wiring. That includes: using the right materials for the job, making connections carefully with the right tightening torques, and following the national electric code (NEC) for some things that are unique to solar, such as sizing breakers and staying within the limits of your panel for second power feed.

Disconnecting DC circuits is also slightly more complex than AC circuits. The connectors are engineered to stay together until you use a special disconnect tool (or a few sharp pointed probes and an hour of fiddling). There is also a more complex sequence for turning off power safely. But it isn't rocket science. Just follow the instructions.

Note that you'll be wiring a many-kilowatt circuit. One bad connection can lead to a house fire and/or loss of life. This isn't the time to rush, save a few pennies, reuse materials, or wing it.

A serious electrical supply house (not Home Depot) will be staffed by someone who knows the code and can guide you on the right 240VAC hardware. Solar is very popular in California, so I wouldn't be surprised if large electrical suppliers in your area also know and carry panels and inverters. Local saves shipping charges, which will be a lot for bulky items.

I can't advise you on California dealers but if you find one, ask here and someone else may know.

[FreeMoney]

Disconnecting DC circuits is also slightly more complex than AC circuits. The connectors are engineered to stay together until you use a special disconnect tool (or a few sharp pointed probes and an hour of fiddling). There is also a more complex sequence for turning off power safely. But it isn't rocket science. Just follow the instructions.

Note that you'll be wiring a many-kilowatt circuit. One bad connection can lead to a house fire and/or loss of life. This isn't the time to rush, save a few pennies, reuse materials, or wing it.

A serious electrical supply house (not Home Depot) will be staffed by someone who knows the code and can guide you on the right 240VAC hardware. Solar is very popular in California, so I wouldn't be surprised if large electrical suppliers in your area also know and carry panels and inverters. Local saves shipping charges, which will be a lot for bulky items.

.

Thanks for the advice. This one: "One bad connection can lead to a house fire and/or loss of life. This isn't the time to rush, save a few pennies, reuse materials, or wing it." stands out. I do try to save where I can, but sounds not the time to DIY when I haven't done it before.

[reader2580]

California is currently using the 2017 NEC with California amendments. If you start making changes to the solar system you might need to bring it up to current code.

[J.P.M.]

I've got a 7 yr. old Sunpower 5000x, which BTW is a rebranded PowerOne inverter. Yours is probably similar. If so, and without more info, your PPK value is the max. power output in watts your system has produced since it stated up 7 yrs. ago. What that number is telling you is that at one instant in time over the last 7 years, the system produced an instantaneous output of 3,092 W, and that is the highest power output the system ever produced. The 1,136 (W) is the peak value so far for the day that reading appeared. The (relatively) low daily reading of 1,136 W can have many causes - dirt, cloudy day, system problems, lots of stuff.

From the # of panels and that max. output, I'd guess the panels are Sunpower 327's or similar/maybe 320's. That's a common Sunpower size and has been around as one of their workhorses for a long time. I've got 327's on a 7 yr. old systems and they haven't missed a beat.

I'd clean the panels, or maybe in this case, pay to have them cleaned. BUT ONLY IN THE EARLY A.M BEFORE THE SUN HEATS THE PANEL GLAZING - COLD WATER ON HOT GLAZING CAN CRACK THE GLAZING. Try to do the cleaning on a day that has a sunny day or two on either side of it and compare daily outputs before/after cleaning for a rough approx. of any effects the cleaning has. I doubt that panels are so dirty that output would drop by ~ 2/3 on a sunny day.

Then, find out who the installer was and if day long output from a clean array on a not too hot, but sunny day is <, say, about 2,400 to maybe 2,700 W, give them a call (if they are still in business). Not doing so may void any installer's warranty if someone else works on or touches the system besides cleaning it. If you can't find the installer/they're out of business, get ahold of Sunpower. The panels and inverter are still under mfg. warrany as long as subsequent owners can prove transfer.

[FreeMoney]

I've got a 7 yr. old Sunpower 5000x, which BTW is a rebranded PowerOne inverter. Yours is probably similar. If so, and without more info, your PPK value is the max. power output in watts your system has produced since it stated up 7 yrs. ago. What that number is telling you is that at one instant in time over the last 7 years, the system produced an instantaneous output of 3,092 W, and that is the highest power output the system ever produced. The 1,136 (W) is the peak value so far for the day that reading appeared. The (relatively) low daily reading of 1,136 W can have many causes - dirt, cloudy day, system problems, lots of stuff.

No local installers wanted to do the remove & replace job - they only want to sell you new system. I cleaned the panels with mop, bucket & dish soap. The panels had bird droppings and a layer of soot, It's been smokey in CA for last 7 days, yesterday was first clear day and panels peaked at 1.76kWHh.

Confirmed with Sunpower, the panels installed are 230 watt. SPR230 NE BLK, E18/230 SOLAR PANEL

Considering the inverter is 3k, 2k sized panels makes sense.

OK, back to upgrade thoughts. the panels are 61.39" X 31.42", I want to replace the (10) panels with highest watt panels & replace the inverter to support the new panels, planning on doing this myself. If I am getting 1760 watts out of 2300 panels, (10) 405watt that would get me around 3.1kWh pushing the 3k inverter to max. (10) 380s gets us to around 2.9kWh, safe for the 3k invertor? *this* might be the best bang for buck?

(10) 380w


The input cables from panels to inverter are two strings of cables labeled as follows:

ZLH .00415 ODG
POLAR WK37/13 OK-FT

The cables themselves have 600V CSA TEW 105deg C printed along the cable.

Will the current string of cables support (10) ~400watt panels?

Would be great to find a Sunpower 5000x to swap this one out and support (10) new 405w panels. The current produced power is enough for about %50 of our household with out AC, doubling the power with (10) high power panels seems like the best bang for buck and quickest install.

When I spoke to installer about quoting me install to replace the current panels/inverter, eventually they fess up and say they don't want to do it.

Thoughts?

Thanks

[J.P.M.]

No local installers wanted to do the job - they only want to sell you new system. I cleaned the panels with mop, bucket & dish soap. The panels had bird droppings and a layer of soot, It's been smokey in CA for last 7 days, yesterday was first clear day and panels peaked at 1.76hWHh. I suspect the panels are around ~200 watts each. Going to take a camera and try to get model number of panel. Considering the inverter is 3k, 2k sized panels makes sense.

OK, back to upgrade thoughts. I need to measure current panel dimensions, but I want to replace the (10) panels with highest watt panels & replace the inverter to support the new panels, planning on doing this myself. The input cables from panels to inverter are two strings of cables labeled as follows:

ZLH .00415 ODG
POLAR WK37/13 OK-FT

The cables themselves have 600V CSA TEW 105deg C printed along the cable.

Will the current string of cables support (10) ~400watt panels?

Would be great to find a Sunpower 5000x to swap this one out and support (10) new panels. The current produced power is enough for about %50 of our household with out AC, doubling the power with (10) high power panels seems like the best bang for buck and quickest install.

When I spoke to installer about quoting me install to replace the current panels/inverter, eventually they fess up and say they don't want to do it.

Thoughts?

Thanks

What's your zip ?
What's the array orientation ?
What's the roof to panel clearance ? If it's a reasonable (say ~ 6" or more) you ought to be able to get a peek at the panel nameplate info. that'll have panel STC ratings and other info such as voltages/current ratings etc.
I'd make sure the inverter is the problem before I swapped it out.
If the panels are ~ 61.4" X 41.2 " outside dimensions they're probably > 300 STC W rating.

I spite of the problems you're having finding someone to troubleshoot/fix, I'd take my own advice of your 07/24/20 1420 hrs.

[FreeMoney]

What's your zip ?
What's the array orientation ?
What's the roof to panel clearance ? If it's a reasonable (say ~ 6" or more) you ought to be able to get a peek at the panel nameplate info. that'll have panel STC ratings and other info such as voltages/current ratings etc.
I'd make sure the inverter is the problem before I swapped it out.
If the panels are ~ 61.4" X 41.2 " outside dimensions they're probably > 300 STC W rating.

I spite of the problems you're having finding someone to troubleshoot/fix, I'd take my own advice of your 07/24/20 1420 hrs.

zip:95762

Panels facing West

Called Sunpower and they were able to lookup the model of panel: the panels installed are 230 watt. SPR230 NE BLK, E18/230 SOLAR PANEL

http://cdn2.hubspot.net/hubfs/500705...=1446241810548

I just want more power out of the panels with out forking over thousands of dollars.

[J.P.M.]

zip:95762

Panels facing West

Called Sunpower and they were able to lookup the model of panel: the panels installed are 230 watt. SPR230 NE BLK, E18/230 SOLAR PANEL

http://cdn2.hubspot.net/hubfs/500705...=1446241810548

I just want more power out of the panels with out forking over thousands of dollars.

How much more room do you have ? The annual output per m^2 of panel surface of the newer S.P. 360's will be about 20 % more than the older 230 W panels. So, for the same footprint you might get ~ 2.5 kW or maybe 7 panels and a lot of design considerations you're unaware of that'll bite you in the butt if the AHJ doesn't.

A basic and necessary first step question or two: What's your annual electrical load and how much of it do you want to replace w/ PV ?

Also, check w/ your POCO. If you do have the roof space, know that existing systems are limited to < 10% or 1kW increase in size (whichever is greater) w/out a reapplication for a new NEM agreement and all the hassle that goes with it. The local AHJ will also probably need to get involved.

I appreciate that you want to save money and not waste materials. Hell, I'm so cheap I take my glasses off when I'm not looking at anything. However, for all the B.S./hassles, you may just might want or be required to start from scratch. The way the jurisdictional bore-ass could go may mandate you do that anyway, and considering that most vendors won't touch an exiting system, if you want a bigger system, that may be the only practical way to do it.

[Ampster]

Hi Solar Gurus,

We purchased a home near Sacremento, CA area which has a Solar grid tied system, moving in early August. From what I can tell, the home has (10) panels on the roof, a Sunpower inverter. Which might be one of the following models:
.............
Looking to upgrade. Considering there is a rail for 10 panels, cheapest upgrade might be to drop in (10) 350ish watt panels (if the inverter will support it)? Any suggestions?

Thanks

If the upgrade path including new inverter looks too expensive you can always add some capacity with a second circuit of microinverters.I added 1kW of capacity for less than $1,000 using used Sunpower panels and new IQ7 microinverters that are RSD compliant.
Perhaps while in Escrow the sell will give you production reports from Sunpower and a copy of the Net Energy Metering agreement that is either with PGE or a local utility. That will tell you how much capacity you can add without triggering a new NEM agreement. If they were installed several years ago they are probably on NEM 1.0 which is more favorable than NEM 2.0. I am speaking of PGE NEM rules so until we know the electrical provider it is all a guess.
You can go to PVWatts and run some simulations of existing system to compare with production reports, You can also run some simulations of hypothetical systems.

[foo1bar]

I just want more power out of the panels with out forking over thousands of dollars.

How much room is on your roof?

There's (at least) 2 ways to increase the power you're generating.
1> replace the panels that are there.
2> add new ones.

For replacement, it's still basically like a new installation - only thing you won't (probably) have to replace is the rails the panels are mounted on.
You'll have to make sure there's sufficient space at the edges of the roof to meet the requirements for fire code.
And you'll have to meet the rapid-shutdown requirements.

For adding new ones, the new ones will need to meet those requirements, but the old ones should be grandfathered.