diy solar

diy solar

Adding storage to my Enphase system

This one was a bit odd. The Schneider XW-Pro log file lists it as a "AI Under Frequency".
Too much power generation and grid frequency increases to compensate (which is why the IEC has DERs curtail power when the frequency rises), too much getting sucked out of the grid and frequency drops (the IEC is coming up with rules for ESSes to increase power export in that situation). I think it was just saying it went into anti-islanding because all your neighbor's AC came on at the same time. A peaker plant somewhere was probably having problems. Rolling blackouts should occur automatically if the frequency gets too low (if the grid destabilizes to far I've heard it's a nightmare to get going again).

But what made this one odd is that my internet router crashed and had to reboot.
I have mine on a small UPS just so inverter resets and the like don't lose communications.

What makes this one look very odd is that the fail at 7 pm looks like it switched clean... But ... the battery current stayed at zero for the full 5 minutes.
I hope you have logs somewhere for that so you can see what happened. Sort of sounds like a flaw in the logic, sort of... oh the grid came on so let's switch to it. Then after 5 minutes (as the minimum no-change time) it realized the TOU said to be on inverter so it switched back.

My guess is the router crashed when the grid came back up and the inverter shut off.

That sounds entirely plausible.
 
This is plausible, maybe the grid frequency did dip, and SO Cal Edison had to shut off our area to reduce the load.

I tried looking through the Enphase log to see what it did, but since it is on the output of the Schneider, it is not seeing the grid all the time. And it looks like most of the iQ7 inverters had already shut down due to sun set. This was probably happening to all of the roof top solar power systems in my area, so yes, we were losing all the solar, as people were all getting home from work.

But then at 6:57 pm, vey close to the time of the outage, the Enphase log has this entry.
"PLC security feature enable set to true" then
"PLC security mode active set to true" and
"PLC security use 256-bit keys set to false" and the last entry of the day
"Microinverter failed to report" which I normally see for all 16 after sun down, but this was the last one to shut off at 6:58 pm, and the only one after the odd PLC messages, all of the others had shut down in the 5 minutes before. The time in the Enphase does not match the time in the Schneider, I think they are about 3 minutes off.

There are no grid power instability messages at all. The next log entries are when the inverters wake up the next morning at 6:40 am.

My small UPS failed. I have not gotten around to replacing it. I was not in a hurry as the system had dropped to the XW 3 times without any glitches before this one.
 
But then at 6:57 pm, vey close to the time of the outage, the Enphase log has this entry....
Well well... doesn't that look familiar!

There are no grid power instability messages at all. The next log entries are when the inverters wake up the next morning at 6:40 am.
I can get the frequency the microinverters are seeing from the ivr data (i.e., http://envoy.local/ivp/meters/readings), not sure if that will help you.

...My small UPS failed...
Failed? If you have a 12V battery handy might hook it up to see if all it needs is a replacement.
 
You have a lot of power outages. I haven't had an outage since I got my system up.
I have a lot of learning to do when we do have an extended outage.
 
svetz
I ran your link on my network and got back 8 blocks of data. I see each one ending with "freq" : 60.000
So right now it looks like I am at 60 hz even. I see the first and 4th block show about 241 volts. Is this the Envoy readings? If it was the inverters, I should have more entries.

The battery in the UPS was very weak, but it seems to hold a charge, but I tried connecting another lea acid AGM battery, 17 AH instead of the 6.5 it had. It won't even try to turn on, just reports battery error beep tones. I think the charge circuit failed. The old battery charges up, but only has about 25% capacity now.

ArthurEld
Actually, it is very odd that we had 2 outages in a month. We have gone years here without one. I think the first was caused by them doing maintenance a few blocks away. I think they tripped something. It was not a planned outage, there was no bad weather, and the closest fire was no threat. The grid was down 90 minutes in the early morning as people we heading to work, and solar power was just ramping up. The second outage happened when it was quit hot out, and it was right as all the solar was shutting down at dusk. My area has a lot of solar. Not just on homes, there are several decent size arrays at the schools, the water treatment area, and even a huge group of arrays all along a south facing mountainside. So one theory was everyone has air conditioning running and as the solar went away, the load on the grid climbed and caused the frequency to dip. But I have no actual report of a cause on either one. The second one lasted a bit over 90 minutes. Annoying for sure, but not long enough to be a big problem.
 
I ran your link on my network and got back 8 blocks of data. I see each one ending with "freq" : 60.000
My bad. The frequency might be a setting rather than a measurement, hard to imagine that many zeroes when measuring an actual system and mine is 60.000 too. I'll sort through my notes and see if I can find anyplace else, feeling a bit dubious about it now.
Update: The Enlighten App "Live Vitals" view shows a frequency, so the data's there somewhere.

Mine shows two sections (production/consumption) each section has 3 subsections. The topmost section represents a 240V "combined" view, it has three sub-sections which are the L1, L2, and L3 (for 3 phase, the bottom block should be 0 volts for a two-phase system).

Is this the Envoy readings? If it was the inverters, I should have more entries.
I'm pretty sure these are the CTs readings fed into the Envoy.
 
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My production graph this morning was a little odd. I never saw this before.
iQprod10-04-21.PNG
The two line graphs are the production yesterday, and the production a year before. The bar graphs are today. The weather has been odd today, with odd clouds and cool moist air. It did end up raining after 4 pm. The real odd part is that spike at 9:30 am. Hmmm. That is more pow than I should be able to make with the sun still that low in the sky, so what happened? While the sun was low in the sky, there were no clouds between th sun and the solar panels, so I would have expected it to produce close to the two historical line graphs. But no, it over produced by more than 20%. There were nice white clouds above my panels, and the low sun was reflecting off of them and back down onto the panels as well as the direct low angle light. Pushing 2,500 watts at just 9:30 am is pretty amazing, especially for into October. Even back in May, my best month of production, I was only hitting 2,400 watts at 9:30 am. And yes, I even double checked, both of the days are in daylight savings time. The cloud bounce also gave me a kick of power from 10:45 to 11:15. Obviously total production is down for the day due to the clouds also blocking the direct sun some of the time, but it was interesting to see the boost happen like that.
 
So Cal Edison is at it again.
In effect, they just made my battery system pay off slower, but, no, not really. It just made solar panels worth a lot more.

They just upped the rates again. Not sure when the change went through as I have such low electric bills, I have not been looking at the break down, but here is what they did now.

My lowest off peak rate went from $0.17 to $0.29 per KWH. That is a huge increase amounting to a 70.5% rate hike. So this really makes me want to get the DC charging panels up right now. The extra power my Enphase will push back during the day becomes more valuable. The peak rate in winter did not change, it is still $0.41 per KWH, but the summer rate did go up to $0.47 on Weekdays, but only $0.38 on the weekend. So I want the DC panels to power all of the peak rate, and also keep powering my home overnight. Now that the off peak has gotten so much higher, the overnight is now a cost concern. We are in the winter rate now, and my Sept. bill looks like it will be under $10 thanks to some good sun in col weather, and not needing to run the AC at all.

The EV rate is looking a little more tempting, but then they throw in a fixed $12 a month fee. When my current bills actually fall under $12, that does not sound like a good idea at this time.
 
Ouch, that's quite the increase!

Are you going to permit your DC panels?
I've got a road block on the Arc Fault Detection requirements.

PGE doesn't charge any extra for the EV rate, I should look into those rates again. I don't think it's enough to swallow a $12/month fee.
 
I am kind of torn on the whole permit issue with the DC panels. I want to build it safe and meet or exceed all the codes. But going through the city is a huge expensive hassle here. That "Arc Fault" protection is looking to be a pain. The only charge controller that seems to include it is the MidNight Solar. It runs about $1,000 and obviously won't integrate into the Schneider monitoring software. Adding Arc Fault to the Schneider MPPT looks pricey as well. I found a solar combiner box from Beny that includes Arc Fault protection, but it costs nearly $1,000 without a charge controller at all. You know it is bad when the web site does not have prices, and just has a click for a quote button. And their box is just the arc detection and breakers.
And while looking for this, I may have found something. OutBack Power has a new FLEXware combiner solution.
I wonder if we could use this with the Schneider MPPT unit?
 
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In my searching I did come across the Outback solution, but I forgot about it. I just looked it up again. Wow! I think it's $1400
The Beny seem similar to the "Solar Bos" that keeps popping up in my searches.
I think part of the reason for expense is that they all include the extra expense of a Gigavac contactor.

The Schneider version is $700, no contactor in the box. It does shut down with the RSD at the panels.


Either way, I/we would need RDS at the panel, those are something like $30/panel.

Outback and Midnight both have SCC that integrate AFCI. Both are more expensive than the $500 Schneider charger controller that fits my needs.
I can't see spending $500 on a charge controller and $700 on the AFCI box.
 
That is exactly where I am at as well. The safety system is going to be about 50% of the whole system cost. That is hard to swallow. I get the desire for arc fault protection. DC arcing is a huge danger, but the DIY market just has not gotten there yet. I am at the point, I may just slap a cheapo EP EVER MPPT on a few panels and get it working for now, and then in a couple years, maybe Schneider will have a proper arc fault protected system for a not too crazy price. Or someone will have come out with a stand alone add on system for any MPPT unit.
 
...They just upped the rates again. Not sure when the change went through as I have such low electric bills, I have not been looking at the break down, but here is what they did now.... That is a huge increase amounting to a 70.5% rate hike.
Wow! I recently saw a 9% increase in the cost of electricity and thought that was crazy! Fuel prices were up 60.8% in July from the previous year (FPL breakdown).
 
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My brother and his wife both drive an EV. With the new rates, their electric bill DOUBLED. They were charging over night when their solar does not produce, and they don't have a storage battery. His wife is now only using the level 1 charger while the sun is out. And my brother is doing a partial charge and topping up at work. The Charge Point station near his work is now cheaper than the off peak at home. I bet that will change though.

I had a really sneaky idea.
My home storage batteries are in cabinets, on wheels. There 13 charge stations in my valley, that if you are willing to watch a commercial, you can get a Level 2 charge, for 30 minutes, for free. How tough would it be to add a Level 2 charger input for my home battery? 30 minutes of Level 2 would totally top me up every day. Can my battery bank take 30 KW charging?? And sadly, a 30 KW 240 AC to 48Volt DC charger is going to be expensive. My easily mobile battery bank is 6P14S of 60 AH cells, rated for a 1C charge rate. So they can "safely" charge at 360 amps at 50 volts, or 18 KW. Of course, my BMS in that unit is only rated to 40 amps x 2, so that would need to change. Not to mention, these are also the cells that should not be fast charged to full, or it might catch fire. But it is fun to think about the possibility.
 
Does your brother get less than 100% credit from net metering? So they need to use it when they make it for best value?
 
I'll have to check the detailed electric bill, but what I remember seeing before the rate hike is that they would pay the same generation fee back, but obviously not the taxes. I do not remember about the delivery charges.

Hmmmm.
I am looking over my previous month bill, and I am confused to say the least. There is a new section talking about wildfire prevention cost recovery. So they are charging us for turning off power to reduce the chance of wildfires. It is rolled into a bond fee.

My previous bill included a lot of very hot days, so my A/C ran a lot.
On peak I used 107 KWH but also exported 43 KWH
Mid Peak I used just 41 KWH, and exported 23 KWH
Off Peak I used 439 KWH and exported 189 KWH

In the end, I used a total of 332 KWHs net. And paid $85.07 total after all of the taxes fees NBC etc. That works out to my cost per KWH that I took from So Cal Edison cost me $0.2562 per KWH on average.

On my old bills, I could figure out where all of the numbers cam from, but on this bill, it is very confusing. Here is the energy I exported (-) and the energy I imported in each rate area in Kilowatt Hours.

On peak -43 +107 NET 64
Mid Peak -23 +41 NET 18
off peak -189 +439 NET 250

Totals -255 +587 332

So I expect to see these numbers in the multipliers, but none of them are there. That is why I think there is a rate change mid month. But even then, the totals of the two numbers on the bill never add up to these numbers.

I also see a Baseline Credit split onto two entries. 56 KWHs and 276 KWH at slightly different rates -0.07299 and $0.07368 respectively. This totaled to a credit of -$24.43 and then my service charge of $0.93

There were three lines of NBC's
Nonbypassable charges (NBCs)
CTC, NDC, PPPC 168 kWh x $0.01846 $3.10
CTC, NDC, PPPC 400 kWh x $0.01823 $7.29
DWR bond charge 568 kWh x $0.00580 $3.29 <--- This one seems to be the wildfire charge

Where did those KWH numbers come from? I can't twist my numbers to get 168 or 400 anywhere. I even tried figuring in the baseline credit numbers. It just seems odd. Out of my entire $85.07 bill, these charges are $13.68 of it. That is over 16% of my bill.

Here are the energy charges

Delivery charges - Cost to deliver your electricity

Basic charge 30 days x $0.03100 $0.93
Baseline credit 56 kWh x -$0.07299 -$4.09
Baseline credit 276 kWh x -$0.07368 -$20.34

Energy-Summer
On peak 27 kWh x $0.22703 $6.13
Mid peak -4 kWh x $0.22703 -$0.91
Off peak 33 kWh x $0.17349 $5.73
On peak 37 kWh x $0.23016 $8.52
Mid peak 22 kWh x $0.23016 $5.06
Off peak 217 kWh x $0.17662 $38.33

Generation charges - Cost to generate your electricity

SCE Energy-Summer
On peak 27 kWh x $0.18269 $4.93
Mid peak -4 kWh x $0.10086 -$0.40
Off peak 33 kWh x $0.07379 $2.44
On peak 37 kWh x $0.18381 $6.80
Mid peak 22 kWh x $0.10122 $2.23
Off peak 217 kWh x $0.07341 $15.93

At least these numbers do seem to add up. The two On Peak number 27 and 37 KWHs added up does equal my NET 64 KWHs used, as does the Mid Peak 22 - 4 = 18, and Off Peak 217 + 33 = 250. So my exported did offset imported 1:1 here. So I am being credited the generation and delivery charges. So it is just the NBCs that are one way only. I imported 587 KWHs, but the NBC's were calculated off 568 KWHs. I guess I got 19 KWHs without paying the NBC's on them? And my State Tax was also charged on just the NET imported energy. But that is also just a total of 10 cents.
 
I bought my wife a KIA Niro EV to take advantage of extra energy my system is producing.
Our bill didn't change. We still just pay the connection fee and my wife pays for some kind of surge protection that probably isn't necessary.
We get 100% credit for net metering but once a year they settle and pay us a small amount for any extra. So it is smartest to use it all.
I plan to get another electric car. If my bill ever goes up, I will add more panels.

You have so much motivation Gary. I don't understand much of the information you post but it is very interesting.
Thanks for taking the time to share all of the details.
 
How are your wife and you liking the Niro EV? How many miles have you put on it so far? Any problems yet?
My girlfriend is looking for a new car, and the Niro Hybrid, or plug in are on the short list. I got a hybrid as a rental car for 2 days. I came away with some mixed feelings.

On another thought.....
I was away for work for 3 days, and so my inverter didn't go into charge mode for the whole time. The first day, the inverter stopped powering the house when the battery fell to 52.5 volts, as programmed, and the voltage stayed there for about 32 hours before it dipped at all on the Schneider XW battery summary graph. But then it did start to droop. In 12 more hours it dropped from 52.5 to 52.4 volts. That is still a very light drop, but the next day it fell another 0.1 in 12 hours, and then 0.07 in the next 12 hours. It is not a lot of droop, but it was odd that it didn't start until the battery sat for over 32 hours.
 
The idle load of my XW inverter is variable, at least by my BMS. I believe it also changes abruptly when the charge block or grid support block times hit.

Depending on battery voltage and settings it will pull somewhere about 15-110 watts.
I don't know how much if this is used by the XW vs how much is inverted into AC...

Also, with how the inverter ramps down current to hold battery voltage, that 32 hours could have all been at 100 watts and that was the emptiest 52.5 volts, then once depleted, the battery voltage slowly started dropping quicker.

Does your BMS store history data? Can you see what the current drain looked like?
 
How are your wife and you liking the Niro EV? How many miles have you put on it so far? Any problems yet?
My girlfriend is looking for a new car, and the Niro Hybrid, or plug in are on the short list. I got a hybrid as a rental car for 2 days. I came away with some mixed feelings.
We are happy with the car and we haven't had any problems. I like the full electric better than the hybrid.
My biggest complaint is that we bought at the worst time. The shortage of vehicles caused me to pay full price.

I plan to buy an EV for myself in the next year or so.
 
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