Solar install failing - curious

[Deschodt]

Any experts here ? I'm curious as to the pattern...
My 2y old system (warrantied) started producing 30-40% max of normal output... There's a pretty obvious cutoff on the graph where one day to the next the bar is 30% of normal (similar sun exposure), so I don't imagine it's dirty panels (I cleaned them anyway). If I was guessing it would seem 1/2 the panels would have disconnected but that seems impossible, it's not like a loose plug. Are inverters knows to fail that way ? Delivering less than 1/2 the juice ? I would have thought the thing would work or die completely...

About to find out how good the service is, and what they do for my bill while the system is not making $ for me. Ugh. Also less than impressed with the monitoring. I spotted the issue, called, and then and only then did the system display "underproduction issue being monitored" LOL. I'm the sensor apparently. All in all I'd buy a smaller system cash, instead of leasing a big one like I did, in hindsight.

[Evans, Marv]

I would suspect it might be an issue with the reporting equipment. I had an ongoing problem with mine seemingly going offline periodically and indicating no generation. The company sent techs out, but they couldn't identify a problem, and the system was actually produciing full power into the grid. I just couldn't see it on my end. In the end it was me who corrected it by figuring out it was one of the monitoring modules between the panel and my conputer. I got the numbers off the modules, replaced the one inside the house, and the problem was solved. If your system is still under warrantee (or not), whoever looks at it can tell you if it's generating 100% and not reporting it or if there is some kind of discontinuity in the wiring at the panels.

[Deschodt]

Originally Posted by Evans, Marv

I would suspect it might be an issue with the reporting equipment. If your system is still under warrantee (or not), whoever looks at it can tell you if it's generating 100% and not reporting it or if there is some kind of discontinuity in the wiring at the panels.

Thanks for the reply.. I wish it was reporting.. I can look at the Power utility report (not the solar app) and I am sending power to the grid like mad in march. In April, peanuts. I'm apparently consuming whatever little I make and sending nothing out for credit. There's definitely something that went pop... I guess if they ever show up as promised I'll find out ;-)

[3rd_gear_Ted]

The newer panels have an inverter on each panel.
Get a clamp on AC amp meter to check each panels output.

[Deschodt]

yeah apparently the inverter is fine.... but one set of panels have a bad "optimizer" if I heard/remembered right, and that shuts down whatever's downstream or that line. So I'm running on 50% of panels and 10% of that goes to the battery in the first place.. The system was not "mapped" properly upon install so they need to come back and remap it and then replace the bad bits. Lovely... I'm hearing they do reimburse for underproduction - we shall see... Looks about as reliable as those solar garden lights I buy and throw away after one year ;-)

[red-beard]

Looks like you have your issue solved.

Originally Posted by 3rd_gear_Ted

The newer panels have an inverter on each panel.
Get a clamp on AC amp meter to check each panels output.

Not as common as you think. The cost for the install is much higher for microinverters than a string inverter. You are running a split phase line at 220-240VAC from panel to panel instead of just using the solar panel connectors to run a single line typically at 600VDC-1000VDC.

If you have shading issues, or anything that can cause a single panel to drop out, microinverters are better. If you have a battery-based system, DC charge controllers are much better. The "optimizer" thing never made much sense to me.

[Deschodt]

Originally Posted by red-beard

Looks like you have your issue solved.

yes and no... sill 1/2 broke but issue may be identified. More delays, more parts, they need to remap the thing.. you'd think a company that does nothing but solar installs would have those parts in stock.... And then the contract stipulates that if they underproduce, it's only measured at true up time by calendar year end - I may get a refund, but really what it means is since I was over producing before, and now is the best time (sun and no AC) I will lose a lot of juice that I was getting before and probably not get any $ back.. I am unhappy I signed on the dotted line for the way they do business, so let this be a warning to all: if you want solar, PAY for it. Yourself. Own it. If is means you can afford only a smaller system, so be it.. but own it

[Evans, Marv]

I paid for my system. I didn't think it wold pencil out any other way. I think people need to be careful choosing a company. The solar industry is going through some instability - if I read the situation right. Not doing your researh and using a company that may not be around could put a crimp in your warrantee situation down the line. The local utility here (SDG&E) pays what I guess is standard for extra generation. Their whosale rate is two to four cents per kWh. I gave them back close to 3 mWh yearly (my system was sized at a 10% overage) and got paid back a big $100 give or take. So for me, getting paid for extra at true up was a bust. That was one of the determining factors in buying an EV. I have to pay a little now, but I'm not giving my extra power away.

[red 928]

Originally Posted by Deschodt

... Looks about as reliable as those solar garden lights I buy and throw away after one year ;-)

Don't know about solar panels as such,
but I do know about cheap garden lights

They have a rechargeable battery in there (AA or AAA)
and that is usually what goes bad after a year.
Each light can have one or more battery, the bigger lights
or strings can have three or four batteries.

I buy replacement rechargeable batteries at amazon for not much $$$,
usually get many times the life from my garden lights.
Plus I upgrade to a more powerful battery than
the cheap ones they can install from new,
which makes the lights stay on longer.
I have some string type lights similar to those pictured below
going around the patio cover and they sometimes stay on
until dawn in the summer.

[red-beard]

Batteries are about to get a WHOLE lot cheaper

Sodium-Ion batteries are now in commercial production. When they scale up, they will operate similar to LiFePo4 batteries, lower cost and cannot catch fire.

[Rusty Heap]

Bought 2 "800 watt" solar panels.......yeah right, 100 watt panels with false advertising.

Still, as a EE I'm pretty damn impressed as yesterday I tested a cheap no-name flexible membrane panel for actual output. Going to put Solar on a RV trailer.

In full noon day sun, it was outputting ~20 volts with no load.

I put a 10 watt 3 ohm resistor across the panel output as a load. Hah, resistor started to get real warm. Measured 3.5 amps under load at ~12vdc. So it was outputting about 42 watts.

That was with one panel, I have 2. So will be able to trickle charge the 4, 6VDC golf cart batteries at about 6-7 amps which is a pretty high trickle charge!

Not too shabby for under $200.

https://www.amazon.com/dp/B0D1KL1FLK?ref=ppx_yo2ov_dt_b_product_details&th=1

[wdfifteen]

They are out here installing a new inverter on my system now. The original lasted 13 months before some internal failure.
I noticed a bird trying to build a nest on top of the cooling fins. Don’t know if that had anything to do with it.