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[rover67]

These what I see for now, its a 5kw system FWIW. 5kw inverter and 18 x 295w panels with 18 optimizers. My power will clip on a real sunny day in summer since the inverter is a 5kw unit and the panel output is slightly higher.

 

[rover67]

Example of clipping:

 

[DaveInDenver]

Example of clipping:

What inverter(s) are you running? Wondering specific model or specs, if you know them.

I'm leaning towards Tim's system is 17 x 250 VA (W) inverters is what's going on.

 

[rover67]

Its a SolarEdge SE5000H-US With 18 x SE P320 Optimizers and 18 x Solarworld Sunmodule Plus 295W Panels

https://www.solaredge.com/sites/default/files/se-hd-wave-single-phase-inverter-with-setapp-datasheet-na.pdf

 

[DaveInDenver]

Its a SolarEdge SE5000H-US With 18 x SE P320 Optimizers and 18 x Solarworld Sunmodule Plus 295W Panels

https://www.solaredge.com/sites/default/files/se-hd-wave-single-phase-inverter-with-setapp-datasheet-na.pdf

That makes sense. That model is 5000 VA and that's exactly where you're clipping.

You also have plenty of input margin, 18 * 295 = 5,310 watts.

 

[rover67]

Yep, that's how I figured it was going to work when I designed the system with headroom for more panels... I only wish I would have gone with a 7600w inverter given the efficiency they are rated at but hindsight is 20/20. Initially I had the system designed around a 3kw inverter and 2950w worth of panels and did the initial build with 2950w worth of panels with a 5kw inverter instead.... I thought that was decent. Pretty immediately after I finished I added 8 more panels since the cost was negligible. Anyhow, That's also why I just looked at Tim's graph and instantly just thought "clipping" but I wasn't looking at units.

 

[DaveInDenver]

I believe Tim said he had Enphase so just picking arbitrarily the IQ7.

Knowing the exact model would determine if this line of reasoning makes sense.

But 240 VA x 17 = 4080 VA and looks like they can handle up to 350 watts, so would be safe with his 320 watt panels. So perhaps they were supposed to use the IQ7+ at 290 VA, like I was saying, like a BOM mistake (simple typo) or supplier mistake or sourcing issue with the one sales promised.

 

[nakman]

Marco that's exactly what I was curious about, thank you. So your system on paper is 5,310 watts, almost the same as mine actually a little bit smaller (5440). So at a 90% threshold saving a little room for spikes, that's 4779 watts, or 4.8 kW. And dangit wouldn't you know it, your graphic example of "clipping" has that mark right at 4.8.. maybe even a little higher. So your system is doing exactly what it should be, IMO.

And down here, I'm capped at 4.1.. I was told today there's a software update they're pushing to my inverters, and to give it 30 hours or so to catch up. So I've got another call scheduled for Monday with the tech guy.

 

[DaveInDenver]

Call me weird (yes, I know, I know) I'd put eyeballs on name plates to make sure I got what I paid for.

Marco's is clipping at 5 kVA because that's what his inverter is designed to do.

 

[nakman]

Dave you're correct on the IQ7, I have had a few calls now trying to understand why they aren't IQ7+ which would have given me the expectation I had. But I'm also tripped up on the AC to DC conversion here, so apparently shouldn't be looking at the data so closely. The fact that I am clipping for 80% of the day is supposedly a positive, and my kWh numbers seem really good for this time of year. Anyway my attempt to push back and get my inverters upgraded was essentially denied.

Looking at kWh per year, my usage is about 7100. My system is supposed to get me 8000, average 22kWh per day. yesterday I made 25. Bottom line is my system is doing better than I was promised and I need to shut up and be happy with it.

So I'll now switch gears back to Xcel energy, and figure out when I'll start to receive credit for solar production.

 

[Romer]

My system is 9.9kWh max system of 27 370 Watt panels. I did have an issue were Namaste came out and quickly replaced a defective optimizer

I have seen the system peak at 7.4 watts, typically around 6.8 wkH around noon). There is no clipping that I can see and expect more when the days are longer and the angle of the sun is more in line with the panels

On a good day I am getting 32kWh of production which exceeds my use

It could be I am limited now and just not hitting the part where it clips, but I don't think so. Namaste has been real good about describing the system to me and explaining my questions

I also learned through them why the inverters were off between midnight and before sun down

The system will utilize a single battery overnight until it gets close to 50% and then will transition over to the other battery, so looking at just the day plots (since Midnight) has mostly 1 battery through an inverter until the sun takes over. That made Inverter 2's production seem out of whack with Inverter 1. When I then looked over a two day period and saw the ways the batteries discharged, it made sense to me

Not sure if this helps you at all Tim

I find myself watching the status during the day like I need to know constantly what is going on

 

[nakman]

Ken, what kind of inverters to you have?

 

[Romer]

To split the loads between the two batteries I have two SolarEdge SE6000H EnergyHubs along with the SolarEdge Power Optimizers. My Panels are 27 LG370N1C-A6 370 Watt PV Modules along with two LG ES RESU16H Batteries

 

[Romer]

This is the design and as you can see the two inverters are wired in Parallel at the main box which doubles the available power. That enables me to have more loads on if the Grid goes out. The only things I lose in a Power outage is the Oven, Dryer and AC Compressors. I can change that if I want later on if I want to. I will see what the draw over the summer is

 

[nakman]

Ok a couple months in and I've decided to ride out the year then assess if I want to go through the trouble of swapping out my inverters, to boost up my output. I have also learned that adding a hot tub and EV has about doubled my electricity usage, at least in February, to the point where our bill is about the same now as it was before we added solar. Just doesn't feel like I'm netting much savings here, but not ready to make any decisions yet based on only a couple data points.

I did call Xcel though after my lasts bill, wondering how I used 1300kWh this year when last year I used 700kWh in the same period, thinking something may not be right with their net meter? And can they tell me how much electricity they received from my system... I was promptly correctected that Xcel has no idea how much solar energy I produce- all they know is what the meter tells them, so if it spins one way that's me making power, if it spins the other way that's me using power, and I pay for what they measure that I use.

So now I'm back to looking at my output and trying to decide if there's an ROI in upgrading the inverters- would be a ~$2k event so my gut says it's probably not worth it. But here's a typical graph now on a sunny day:

As you can see there are a good 4 hours now where I produce 4.1kW, or 4100 watts. My panels (17x320) could technically max out at 5,440, but we could peel that back to 5100watts just to be a little more conservative, and to make the math easier. So right now in April there are 4 hours per day where if I had better inverters I'd get another 1000 watts/hour. Currently I top out at around 35kWh in a good sunny day.

So just trying to run the math out here, if there are 20 days/month for 6 months where I could net another 4000 watts, that's another 480 kWh of electricity, right? I think I pay $0.158 per kWh, so that's $75? that's a 26 year ROI on swapping the inverters... doesn't seem right.

 

[coloradoadams]

I'm curious if anyone else on the forum has a complete off grid solar or wind system? We have an older system, 2500 watts worth of panels, lead acid batteries, 2 wind turbines, old school Trace inverters. The system works pretty good, but definitely has some quirks. We are pretty power conscious in the winter and during longer periods with low sun/wind. It would be nice to have someone with a similar system to troubleshoot issues and share ideas with...

 

[RayRay27]

Ok a couple months in and I've decided to ride out the year then assess if I want to go through the trouble of swapping out my inverters, to boost up my output. I have also learned that adding a hot tub and EV has about doubled my electricity usage, at least in February, to the point where our bill is about the same now as it was before we added solar. Just doesn't feel like I'm netting much savings here, but not ready to make any decisions yet based on only a couple data points.

I did call Xcel though after my lasts bill, wondering how I used 1300kWh this year when last year I used 700kWh in the same period, thinking something may not be right with their net meter? And can they tell me how much electricity they received from my system... I was promptly correctected that Xcel has no idea how much solar energy I produce- all they know is what the meter tells them, so if it spins one way that's me making power, if it spins the other way that's me using power, and I pay for what they measure that I use.

So now I'm back to looking at my output and trying to decide if there's an ROI in upgrading the inverters- would be a ~$2k event so my gut says it's probably not worth it. But here's a typical graph now on a sunny day:

As you can see there are a good 4 hours now where I produce 4.1kW, or 4100 watts. My panels (17x320) could technically max out at 5,440, but we could peel that back to 5100watts just to be a little more conservative, and to make the math easier. So right now in April there are 4 hours per day where if I had better inverters I'd get another 1000 watts/hour. Currently I top out at around 35kWh in a good sunny day.

So just trying to run the math out here, if there are 20 days/month for 6 months where I could net another 4000 watts, that's another 480 kWh of electricity, right? I think I pay $0.158 per kWh, so that's $75? that's a 26 year ROI on swapping the inverters... doesn't seem right.

So the BS thing with Xcel is that they don't read the meter monthly. They use your estimate or average usage from the past. So if you go a full year of solar usage you should see a significant usage drop. I noticed this too with my system because my first couple of bills were way off and I had to call Xcel almost weekly for a while if felt like. Xcel takes a complete hands off approach to residential solar.

Quite frankly I think as customers we are getting ripped off and should probably file a class action suit against Xcel for not charging us for what we actually use vs. estimated usage. Maybe I am way off and over reacting?

 

[DouglasVB]

So the BS thing with Xcel is that they don't read the meter monthly.

You guys still don't have digital meters that are read electronically, remotely, and automatically? https://en.wikipedia.org/wiki/Automatic_meter_reading

Back before PG&E came through my grandma's part of Fresno, CA she had an ancient mechanical meter inside her garage that she had to read herself every month and then set the dials on a cardboard representation of her meter that sat in the window by her front door. Some months PG&E would estimate her usage rather than come read that piece of cardboard. Then they got a new meter reader and some months stretched into some years when the meter reader was finally busted for sitting at a coffee shop every day and faking all the meter readings. After the person got caught, my grandma's meter was read accurately. The bill was quite a surprise but was shortly followed by a lawsuit from local residents who were impacted. As I recall she ended up only having to pay a portion of that bill and her area was shortly thereafter converted to the new digital meters that automatically report usage to the power company.

 

[60wag]

Your newer solar systems may be different than my former system in that it produced lots of power in the summer when the arc of the sun was high in the sky compared to the winter, when the sun path was lower, it produced much less power. This may have been due to the angle that the panel were set on the roof. Either way, I expect you will see some noticeable change in power production throughout the year.

 

[thelal]

Interesting reading all the R&D and real usage ye guys are seeing.
Not quite in the same sunny climate (I'm in Ireland ) but longer term hoping to have some solar capability. Green party here pushing but still not enacted getting paid for excess back onto the grid

Anyway back to 80s wrenching!