diy solar

diy solar

Adding storage to my Enphase system

It's official, my Sept. to Oct. electric bill is -$47 for the first time in 4 years of having solar panels, I got a credit this month instead of a charge. The battery system and the weather had a lot to do with it, but the week with the DC panels working also helped. In 2020 for this same month, my consumption was 607 KWHs and that was with the solar panels already installed. Last year, with the battery sort of working, but needing the manual charge cycle, I did far better, getting it down to just 103 KWHs of usage. Then this year, with the PLC controlling the the XW charging and a week of the additional DC panels, the month ended at -43 KWHs of net export.
 
Guy wires from high corners of array over to parapets, just above the roofline?
I'd like a rigid truss structure, but I'd take a parasail over the alternative.

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It's official, my Sept. to Oct. electric bill is -$47 for the first time in 4 years of having solar panels, I got a credit this month instead of a charge.
Didn't you also had a climate credit on your bill ?
My utility gave me a $59 credit this month on behalf of state of California.
I will take it though ;-)

This is from my transportation provider only (SCE)
Screenshot from 2022-10-19 22-20-37.png
Screenshot from 2022-10-19 22-20-55.png

On top of that I have my CPA where I get the generation charges from.
 
Time for a small update.
We had some real nice sun today, up until 3:45 pm that is. Here is the production trace from the Enphase panels.
Enphase10-19-22.PNG
You can easily see the dip in production when the clouds moved through. but the peak power hit 3,300 watts or 68.75% of the panel DC rating. Panel angle is not ideal for this time of year. Here are a pair of screen grabs from the Bouge RV DC charge controller. It does not provide a trace like Enphase does, but it has some useful data.
IMG_2149.PNGIMG_2150.PNG
The image on the left was taken just after noon, 12:17 pm on the phone screen. Peak power by then was at 660 watts, it was currently producing 638 watts, pushing 11.48 amps into the battery bank, with the battery at 55.6 volts. The voltage reads a tick higher than my Fluke, but not enough to make a huge difference. At that point, it had only pushed 1522 wat hours into the battery. The right hand snap was taken just before I started typing this up, 10:43 pm so the sun is long gone. Solar input is 0 volts and mode changed from MPPT to NULL. Peak power did manage to hit 669 watts. That is 66.9% of the 1,000 watt array, so about 2% below the Sil Fab / Enphase panels. Total energy pushed into the batteries totaled up to 3,731 watt hours, or 3.73 sun hours. The Enphase did 20.1 KWH or 4.19 sun hours. Again, only 89% of the total production of the Enphase. I know I have some morning and evening shadows, but so does the main array. This shows how good the Enphase inverters are, and how well my Sil Fab panels are holding up to their specs after 3 years of So Cal sun. I think part of it is the MPPT routine in the Bouge controller just seems to sweep too far as it is constantly searching for the maximum power point. As you see, the peak power looks really good, why is the whole day production so much lower?? It's not horrible, but I was hoping to hit 95% of the Enphase gear. How much is the panels not making their full rating, and how much is the cheap charge controller?

The XW-Pro inverter/charger took just 8.6 KWH's from the Enphase system to charge the batteries. And here is why...
XW-Batt_10-19-22.PNG
The batteries reached my absorb setting of 56.98 volts at just 1:33 pm. Absorb only lasted 3 minutes and the XW went to standby. Technically it actually went to "Grid Sell" but since the Enphase was selling more than my current setting, it just sat there. But then a funny thing happens. For the first time ever, I see the battery voltage go up while the XW is not charging. So the charge power coming from the Bouge RV charge controlle did cause the voltage to go up. AND it hit 57.2 volts. The is the setting I have in the Bouge for max bulk charge. I think the production was only 90% of the Enphase sun hours because it may have dropped down to absorb mode for a while before the XW started pulling decent current.

From 3:49 to 3:53 pm, the XW actually pulled 3 amps from the batteries, to keep the grid power zeroed when the clouds went over and the production from the Enphase panels dropped. That was not enough to dip the battery voltage at all. At 4:50 pm, the sun was going down enough that the XW current finally starts to ramp up to keep the grid power zeroed. Before this point, I was still exporting for 50 minutes into the peak rate time. It took almost another hour for the battery voltage to fall again to 57 volts. The XW was only pulling 9 amps, as the DC panels were ramping down as well, but they were still helping a little. After 6 pm we used the microwave. That always yanks the battery down a bit.

And here is the real proof that the DC panels are making a big difference. XW-Energy_10-19-22.PNG
This is current, right now at 11:29 pm. Th XW only charged 8.6 kWh into the battery, and it has discharged back out 10.1 kWh. For the week so far, it has discharged 2.3 kWh more than it has charged. The "Grid Energy" at the bottom is a bit misleading as it measures all the Enphase export as well. Today w took in just 9 watt hours, but exported 6.9 kilowatt hours. The whole week so far is 2.4 kWh in and 22.7 kWh out. The load meter only counts what goes out to the load from batteries. So that is 9.6 kWh today and 39.1 kWh for the week so far. But the total output from batter also includes a chunk of the Grid Energy (Sell), but without the sell from the Enphase.

This is where it gets a bit odd trying to keep track of 3 separate systems that don't talk to each other.
 
Didn't you also had a climate credit on your bill ?
My utility gave me a $59 credit this month on behalf of state of California.
I will take it though ;-)

This is from my transportation provider only (SCE)
View attachment 117104
View attachment 117105

On top of that I have my CPA where I get the generation charges from.

You are correct, that is a good catch, I had to look closer and found that on there. And our numbers are very close, because this is just the taxes and "non bypassable charges". Since that credit made the bill go negative, they did not show my energy production credits. That is shown lower on the bill. I had -43 kWh's of net export, so I also have $12.80 credit roll over to next month. So they gave me 29.8 cents per kilowatt hour, and charged me 11.63 in all the fees and taxes etc. So without the "Climate Credit", I would have still had a negative bill of $1.17

This is my first month of the new Net Metering plan year, so my entire credit is the $12.80 but I have them bill me any positive balance each month. So if the bill totals up positive, they apply the credit that month. Since my original grid tie system was not able to over produce, I really hated the full year true up. It took a few months of the $6 and $10 bills before I realized I was only paying the taxes. And my energy usage that first year was totally up. At the end of the full year true up, I got slammed with a nearly $1,200 bill. It's only $100 per month on average, so I would much rathe pay that. But now that I added the battery and the DC panels, I will net out much closer to zero. This was the first time I got a net export total for the Sept. - Oct. billing month. And the DC panels were only up for the last 6 days of the month. Next month may be interesting. But we are getting shorter days, and more likely to have some cloud cover as well. The Enphase panels produced 596 kWh's in Oct 2021, In Sept. 2021 it was 687 kWh's, so it will likely fall off about 90 kWh's this coming month. My home energy usage does not drop that much, in fact if I have to run the furnace in will go up a bit. But the DC panels are adding about 18% to the Enphase production. By that estimate, I could possibly see 107 kWh's from the DC panels. So I just might zero out Oct. - Nov. If I get the additional 10 x 100 watt panels, it will easily do it.
 
It took a few months of the $6 and $10 bills before I realized I was only paying the taxes. And my energy usage that first year was totally up. At the end of the full year true up, I got slammed with a nearly $1,200 bill. It's only $100 per month on average, so I would much rathe pay that.

Apparently that's how the rooftop PV companies manage to disappear down the road before customers realize their bill didn't derease as much as expected.

If you paid $100 for consumption some months, and in later months had net exports, would those offset prior consumption so utility would have to refund you in cash?

Utility offers levelized payments for people who don't want larger bills some months. Once you understand how much is accruing each month you could just let the cash you would have paid pile up in your bank account until true-up.

Most of my bills are on autopilot. Credit cards auto-debit minimum due so if I misplace a bill it won't be late, and I can choose where to pay the balance from if it is big. Just AmEx with full amount due at once I handle required payment manually. Some larger annually billed expenses go on a credit card so the auto-debited amount is modest.

"Slammed" by $1200 electric bill (once in a year)? You don't wanna see my water bill ;)
"Water is life; don't waste it." I haven't figured out how to make H2O from photons.

Now that you have DC as well as AC charging, does all surplus power after battery full get exported to grid? Or would it be necessary for you to slow charging from AC, allow export, to leave room in battery for DC coming later in the day?
 
Now that you have DC as well as AC charging, does all surplus power after battery full get exported to grid? Or would it be necessary for you to slow charging from AC, allow export, to leave room in battery for DC coming later in the day?
Right now it is a manual balance act. The DC source is still quite small compared to the total, so yesterday was the first day I think it may have gone to absorb and didn't actually use all of the power from the panels. But the maximum lost power was small if it happened. The problem is that it is difficult to predict exactly how much I am going to get from the solar panels. If I miss too low, the battery won't get full, if I miss too high, the DC charge could curtail. With a little code change in the PLC, I could have it increase the offset value to have the XW also export a little more power to match what is coming in from the DC panels once the batteries go above my desired maximum voltage. I might have to ad a modbus DC current or power meter to get all the data I need to do it perfectly. Once the battery voltage hits 57.1 volts, raise the export power by the same wattage as the DC panels are producing. If the battery voltage drops by 0.1 volt, remove the offset again to stop the export. That keeps the battery full until all solar stops making power while exporting any excess production. It's doable. I am still well below the safe charge limit for the batteries, so for now, I think I will lower the max voltage from the XW by 0.05 volts. I still want to fill up the battery as much as possible while the electric rate is cheap, and then if there is going to be export, have it happen as much after 4 pm as possible to get it at the higher rate. That 0.05 volt should give me enough "room" for the extra now, but come spring, when production increase without the A/C running, I will need to get "smarter".

I guess I am a bit soiled here, my water bill is cheap. I don't remember having a monthly water bill over $250. This month was just $60 since the lawn sprinklers barely ran. And my son moved out, so it is only 2 people taking showers, and half the laundry. We also lost his gaming PC and XBox electric loads. But I have to send him rent money now.

I have not gone negative on electric use for a whole plan year. Any credit balance carries to the next month, and has been getting used up. If I do end up with a credit balance at the end of a year, they would send me a check for it at my billing year end. That is the Aug.-Sept. billing period for me, which coincidentally happens to be my worst consumption month, so it has typically burned up any credit balance.

As I started typing this, the DC solar panels were already making 70 watts, pushing 1.4 amps into the battery bank, and the Enphase inverters are just now starting up. So I got 35 watt hours (not a whole lot) from DC before I got any from the Enphase system. But just in the last 15 minutes, the old panels are now up to 350 watts. 5 times the power is right where they should be. If the arrays were the same size, that early start would mean a lot more.
 
I had the first odd thing happen with the new DC panels and the Bouge RV charge controller.

I worked a long day 2 days ago, so I was not able to check in on the system. When I got home, it showed that it only stored 2,447 watt hours from the DC panels. That is not bad, but I was expecting over 3,500 as it had done every day before, and it was a good sunny day. The Enphase did well at 19.8 KWHs, so I was not sure what happened. Then yesterday we had heavy clouds and rain, so the production was horrible. Both systems did all they could, and it did get enough charge that it made it past 9 pm on battery, so I was ok with that.

Today was nice and sunny, so I was watching it again, but I went out to lunch. When I got back and checked it about 3 pm, instead of MPPT mode, I saw it show BOOST mode. Even though the voltage was not up to my battery voltage setting, it was in their absorb mode and limiting the current way down. The solar input voltage was way up at 97 volts, but only showing 5 watts. I went into the settings page, and it had reverted all back to factory default. It was back in "GEL" cell mode and auto detected 48 volt system, so the Bulk limit was set to only 56.8 volts. I don't know how long it was in the "BOOST" mode and limiting current. The battery voltage in the XW hit 56.8 volts at 2:33 pm, but the Bouge controller tends to reed a bit higher, so I think is started limiting even earlier. I can see a slight drop in the voltage slope starting around 2:11 pm. I am guessing that is when it started to current limit.

I went into the Bouge settings on the app and set it back to "USE"r mode and had to re-enter all of my settings. When I did, it went back to pushing around 600 watts. Now as the sun is setting, it has pushed a total of 3,801 watt hours today. So the production is back to what I expect. I don't know what might have cause it to lose the settings. I will have to watch it and hope it does not do it again. At least it is a fairly "Safe" failure. I would much rather have it stop charging than push the voltage up too high.

The Enphase system did amazing today, pulling 21.7 KWHs. That is the best the system has done on this date ever. Too bad, I may have lost an 30 minutes to an hour of production from the DC panels. But they still did well at 3.8 KWHs. That brings my total solar production today up to 25.5 KWHs. The extra solar from the Enphase panels put 12.7 KWHs into the battery bank. Add in the Bouge DC charge and that is 16.5 KWHs went into the batteries. With the bad production yesterday, they were drained down to 51 volts before 10 pm last night. With the good solar production, even with doing laundry and the dishes, it still topped up the battery bank to 57 volts at 3:17 PM. The Bouge kept pushing it's 10 to 11 amps while the extra Enphase power was exporting. The days are getting shorter though, it stopped exporting and had to start using some battery power before 5 pm. When we go off of Daylight Savings Time, that will mean, running on battery right at 4 pm.
 
My only guess at this point is maybe I hit some kind of reset on the app?? If it does it again, I will then be writing to Bouge to see what they say.
 
My system hit a new milestone today. The NewPowa panels an Bouge RV charge controller exceeded 4,000 watt hours. It was fairly cool today, so the panels performed better, and there were virtually no clouds as well. I started typing this at 5:50 pm, and both the SilFab / Enphase and the NewPowa / Bouge RV systems are still making a little bit of power, but the fun part is, the 4,800 watts going into the Enphase system is making virtually the same power as the 1,000 watts going into the Bouge. Both are showing 20 watts. The sun is very low in the sky, there is a huge shadow across half of the SilFab panels, and all production will be done very soon. And sure enough, at 5:54 the Enphase system reported zero power. The Bouge is down to 13 watts. I have to wait abut 6 more minutes for Enphase Enlighten to update for the total watt hours today. The Bouge is still counting up, but it is basically done at 4,019 watt hours with only 0.27 amps still going into the battery system. Since the Enphase is no longer helping, the XW-Pro is pulling 11 amps out of the batteries, so the small current from the DC panels is just barely slowing the discharge now.

Here are a couple interesting pictures.

IMG_2169.jpg

It's a little hard to see in this picture, but when I took that at 4:36 pm, the front row of panels is casting a shadow onto the very bottom row of cells of the back row. So I think from even before this, I was pretty much down to just the front row doing all of the work.

I have not changed the settings in the XW-Pro yet. It is still set to charge to 56.98 volts. With the help of the DC charging, it hit 56.9 volts by just 12:37 pm. At that point, I cap the max charge rate to 25% from the XW. But with the 25% still, and 12 amps coming from the DC charging, it only took 11 minutes to get to the 56.98 volt Bulk Charge limit, so the XW fell down to absorb, and the Enphase power started exporting over 2,000 watts. Absorb only lasted 6 minutes until it saw the voltage was holding with the current down to zero. Here is the graph as of 6:13 pm

XW-Bat_10-24-22.PNG
But this graph also shows something else. At 2:35 pm, more than 1.5 hours after the XW stopped it's charging, the battery voltage, being reported by the XW stats to show the voltage climbing. The DC panels are really doing their job here. Since the old solar panels are still fully powering the house, the battery bank is under essentially no load and even the small 8 to 10 amps coming in from the small DC array is enough to keep them charging higher. Now, I still don't want to push then too high, but this is not enough for concern. The original rating for these cells it 4.2 volts per cell which would be 58.8 volts for the 14S battery bank. I se the Bouge charge controller to 57.6 volts to keep it from going back to BOOST mode. The highest voltage the XW reports for the battery is 57.25 volts, and the BMS showed it at 57.20 volts. The Bouge RV charge controller was showing 57.4 with a peak reading showing 57.5 volts. Each cell in my old battery bank, with the JK BMS was showing from 4.085 to 4.087 volts, yes just 0.002 volts from lowest to highest cell. And the BMS is reporting that as 92% charged.

IMG_2168.PNG
That was back at 4:32 while the DC panels were still making a little power, charging at 1.2 amps into the old bank, a little more is going into the new bank as well. But that is the highest voltage reading I was able to capture. Shortly after 6 pm, the voltage starts dropping as the XW starts using battery power to run my house. Here is the 1,000 watt array again as the power fell to 10 watts, look how the shadows are barely visible under the panels, it is just the light scatter in the clouds making that little power.
IMG_2170.jpg
And as the Bouge controller finally shuts down, the total DC charge power fo the day ended at...
Screenshot 2022-10-24 at 6.27.47 PM.jpg
4,025 watt hours. Peak power hit 706 watts. 70.6% of array rating, and 4.025 Sun Hours of production.
Meanwhile, here is the final production for the Enphase panels today.
Enphase10-24-22.PNG
Peak power averaged for 15 minutes hit 3,500 watts or 72.9% of the panel rating, so still beats the DC setup there. And total energy for the day hit 21.1 KWH out of 4.8 KW of panels for 4.396 sun hours, again, still beating the DC system. It has been pretty consistent, the new DC setup is getting just 91.6% of the sun hours of the old panels. My guess is that both the NewPowa panels and the Bouge charge controller are only getting 96% of their ratings. That is within the "fudge factor" range on a spec sheet, within 5%. So the panels are really just 95 watts, and the 98% efficient charge controller is really just 92% efficient. They might be a tick better than that, and my angles and the shadows are holding it back a hair, but even if that is the best they can do, it is decent for the price to my door, with the free shipping etc. This is a lot better than you get with a lot of the cheaper Chinese made stuff out there. And it also goes to show that my higher tier SilFab Enphase equipment is holding up just fine after 3 years in the hot So Cal sun.

I am temped to take over one of the SilFab panels for a day and see how it performs on the Bouge charge controller. I just don't think I have enough cable to reach the old array, and I don't want to move the panels. If I also then connect 4 of the new panels to the Enphase inverter in series parallel, it should work fine, but by my math, it will clip the iQ7 inverter. The peak sun I got today, even saying they are 95 watt panel, the power of 4 could hit 277 watts. It won't hurt the inverter, but it should clip it at 240 watts for over an hour. But that might not tell me the peak power capability. I would get less power, but a more realistic measure if I series just 2 panels alone. Then the peak power will be around 139 watts. The maximum input voltage of the iQ7 is 48 volts, 2 of these panels will only total up to 45 volts. MPPT tracking range is 27 to 37 volts. I was seeing 80 to 90 volts for 5 panels in MPPT mode on the Bouge. That works out to 32 to 36 volts for a series pair. So it should gather every watt. This experiment could tell me if the panels are week, or the charge controller is not efficient.
 
Here is a small update on my system.

I am 2 weeks into my next So Cal Edison billing cycle. Last year, I had a $120 electric bill for Oct. - Nov. but so far, I am averaging -3 KWHs per day for the first 2 weeks. I only used some grid power on 2 days when we had heavy clouds. It has been getting cold enough at night that my furnace has been kicking on. It looks like it draws 10 amps when the hot surface igniter is on, then drops to just 5 amps after the gas is lit. Last year, without the DC panels, this was causing me to consume 2 to 4 KWHs each day. I would have expected the extra panels to just get me close to zero, but it has pushed it into negative. I am not sure why it seems to be more productive than the numbers suggest. I am only getting 3,000 to 4,000 watt hours a day from the new DC panels, but my So Cal Edison consumption appears to have dropped almost 7,000 watts hours a day from last year. The only real difference is that my son is not here, he is now at college. Was he really using another 3 to 4 kilowatt hours a day? He would leave his TV on all day, and he had a PC and XBOX in his room too. I guess it's possible. Here is last years Oct. to Nov. consumption from SCE.
SCE-Bill-11-21.PNG
I did have the battery sort of working then, but I had to manually start the charge cycles and it did not self track the power. But I was still able to time shift about 10 KWHs from noon time to the evening. So some of the improvement is probably due to the PLC controlling the XW-Pro, but this is a lot more than that. The weather may also have a little to do with it, but still, this seems huge.

Here is the first half of the same time period so far this year.
SCE-Bill-11-22a.PNG
The 29th should also be exporting a bit, but the data is delayed for some reason. So I am using 7 KWHs less each day. It just does not seem possible, not that I am complaining.

Oh, we also did get a new dryer. The old one was also gas, so the difference is really just going to a more efficient motor to spin the drum. And since it holds more, we do less loads, but even that is not enough for this difference. I am thinking, maybe it got warm enough on those two bad days that the A/C ended up kicking on??? If the inside temp goes over 81F, it will switch to A/C mode. It has to get pretty hot out for that.
 
I am only getting 3,000 to 4,000 watt hours a day from the new DC panels, but my So Cal Edison consumption appears to have dropped almost 7,000 watts hours a day from last year. The only real difference is that my son is not here, he is now at college. Was he really using another 3 to 4 kilowatt hours a day?
FWIW, my home office uses about 3.5kWh/day with the lights off and no "projects" running. It can roughly double that with long days and/or doing various little projects.
 
Here are the plots for what my system did on Oct 31, 2022.

Enphase PV Solar production...
Enphase-10-31-22.PNG
The bars are the current day, and the line over the top is how it did the day before. You can see how the clouds rolled in after 9 am. Production dropped by about 1/3.

Here is what the XW-Pro battery did with the PLC controlling it...
XW-Batt_10-31-22.PNG
Since production was good the day before, the battery was powering the house all the way until the sun came up. It was discharging into the inverter at 9 to 15 amps. Then after 8 am, PV solar started taking some of the load, and by 8:50 am, it switched to charging and battery voltage started to climb after 9:10 am. All the places that charge current falls to 7 amps, means the solar production was falling below 400 watts. When that happens, the battery voltage stops climbing. About 2:30 pm, the solar production was not keeping up with the loads, and the PLC turned charging off completely. It turned it back on again for a little after 3 pm. Battery voltage didn't even make it to 56 volts, full charge is 57 volts. At 4 pm, charge current is turned off, no matter how much the PV is producing. The XW starts pulling current from the battery to provide power to the house to try and keep the grid at zero current. I actually do have a little offset built in, so it leans a little to exporting power. Because of the fairly large 1% charge current steps, I have it seek to 100 watts of export. A 1% change is about 70 watts. So if the export exceeds 100 watts, increasing the charge current 1% drops the export to 30 watts. If export falls below 20 watts, it reduces the charge current 1 %, so it jumps to 90 watts of export. I leave the window a little bigger, and I have adjusted the values to make it hold more stable and not keep flipping up an back all the time.

Looking at those 2 graphs, it is obvious that the energy from the PV panels is moving a lot with passing clouds. The Enphase report is only showing the average production for each 15 minute time slice, but the XW graphs shows each minutes, and my system is adjusting the current every 5 seconds. Yes it is over kill, but I do it to be able to respond to load changes. The microwave oven is a good example. It may only run for 1 minute, but it pulls 1,600 watts. The only way the XW knows it has come on is that my PLC sees the power jump in the main panel. And it only sees that when it asks for a measurement. That only happens every 5 seconds. So I am consuming grid power until I take a reading and tell the system so compensate for the power change. The same happens again when the over turns back off. It starts exporting that 1,500 watts until the PLC checks and sees the power draw dropped. Then it commands the XW to reduce export again. So the 5 second polling works well, without being too crazy. If I polled much slower, it might completely miss a short load like the microwave. Or it could miss a cloud going over and cutting solar production also.

The end result is the power consumption from So Cal Edison. Here is the same day, with their hourly power use readings...
SCE-10-31-22.PNG
Because the power peak is so small, the graph scales it up to still fill the height. Look at the left side. My peak export power only hit 0.1 KW or just 100 watts average for the 11 am and 1 pm hours. That is when the sun is shining and the PLC is adjusting the charging. The 2 pm and 3 pm bars show that when the solar production tanked to nothing, I ended up using 0.02 KW from the grid. Yes, that is just 20 watts for 2 hours. At 4 pm, I stopped all charging, even when the sun did poke out again. But it really was not much, hitting just 50 watts of export. From 5 pm, all the way to the next morning (just like this morning) the house runs on the battery and I have it leaning a tick to export, pushing out 20 or 30 watts out to the grid for 15 hours. So all night, I exported a whopping total of 400 watt hours from battery to grid. That is about what it takes to get credit to cover the connection charges and taxes.

This was a bad production day with a lot of clouds, and it managed to cover it. The extra 2 kilowatt hours from the DC panels certainly helped make it happen. But as you can't see, these graphs do not show that DC production at all. On a day with better sun, the battery will become fully charged before 3 pm, and then the extra solar exports a lot more. It can even export quite a bit after 4 pm, getting credit at the higher rate. But none of that is from battery. It is only when solar power is exceeding consumption, AND the battery is already full, or it's after 4 pm, and exporting is worth more than charging.
 
It's impressive how well you have the system tuned! What are your current rates for mid/off/super-off peak? Do you have to change anything on the PLC as you switch to winter tariff?
 
I just went and checked again to be sure I had the current numbers.
NewSCEwinterRates.PNG NewSCEsummerRates.PNG

This is rounded off, and estimates the taxes on just buying power. The credit I get back for exported power is a bit less due to the NBC's and taxes etc.

I never exceed the baseline credit, so I like their new way of showing it on the bill. My rate is actually the lower cost rows.
So now, in winter, weekday and weekend rates are the same at $0.24 from 8 am to 4 pm, then up to $0.38 4 pm to 9 pm, and then $0.27 from 9 pm back around to 8 am again. Ideally, I want to only buy at the 24 cent rate. Most days do make it close to 8 am on battery. But I am not going to go crazy on more panels and battery for just the 3 cent savings. But 14 cents difference is decent. And remember, when I sell, I don't get to keep the full 24 cents even. So the saving from using my own power is even a little more than this shows. When I time shift 12 KWHs. from 24 cents to 38 cents, that is $1.68 saved each day. We are now on that rate for 8 months x 30 days = 240 days x $1.68 = just over $400 saved. Then in summer, the weekday rate goes from $0.25 from 9 pm to 4 pm, and then jumps up to $0.45 from 4 pm to 9 pm. So for 80 days, shifting 12 KWHs it saves me about 12 x $0.20 x 80 = About $190 on Summer weekdays, and the weekend is 25 cents to 35 cents. So saving 10 cents for another 12 KWHs for about 30 days is another $36 or so. I should actually do better than this, but it is a decent rough estimate. $400 + $190 + $36 = $626 USD just from the time shifting. The DC panel power is almost all being used at the high rate, and coming in for free, not coming off of the low rate time. That is 3 KWH of power every day for nothing = 3 x $0.40 average cost x 340 days (might not produce a few days, so be honest) = Nearly $400 worth of power. So between the battery doing the time shifting, and the DC panels, I might be chopping around $1,000 off my electric bill each year. Last year with the battery manually charging, to this year with the PLC doing the charging, my bill dropped nearly $700 with nearly $300 of that savings in just one summer month. This is not taking into account how much is being chopped off the bill from all the SilFab / Enphase panel production to begin with. That is 8,000 kilowatt hours a year, but it is all being produced at the cheapest rate, 24 or 25 cents. The battery is tasked with time shifting it to the expensive evening rate. But even at the cheapest rate, that production represents 8,000 x $0.24 = $1,920 worth of electricity.

I know it is really sort of cheating, but as they keep raising the rates, it keeps making the solar power look better and better. Bu I can't help but remember that before I put in the solar panels, my base rate was only $0.17 per kilowatt hour, all day long. It only jumped up to $0.34 if I used more the 400 KWH in a month. My original solar install pay back was calculated by keeping me remaining electric bill at just the base 17 cent rate, as the solar feed would keep from going into the second tier, let alone tier 3. But NOPE! You now have solar panels, so now you get ToU rates that start at 24 cents.

As long as the production is able to keep up with my demand on the battery, there is no need to change how the system operates from summer to winter. In all cases, I just make sure I don't ever charge from 4 pm to 9 pm and try to zero the grid from stored solar power. The only change I might make, and it would also be year round, would be to block it from using any battery power before 4 pm, even when there is no solar production. If production is that bad, like it was doing today, I don't want to use what little battery power I did save up to zero my power meter before 4 pm. But right now, it is still doing that. It is easy to block selling to the AC1 grid input based on time, but it is actually difficult to keep it from covering the loads in the backup panel. If I force it to "Standby" will it keep the transfer relay closed to pass grid power to the output side?

Today, it used some battery power to run backup panel loads from 2:30 to 3:30 because the Enphase solar was not able to keep up. Yesterday, it was making 1,900 watts at 3 pm, today it was only making 100 watts at 3 pm. That is a huge loss of production. I am pretty sure it will easily make it to 9 pm on battery, so it is not that big of a deal, but it may run down and have to use grid power before 8 am tomorrow when the sun should rise. Today, even with these clouds, the Enphase system was still able to make over 14 KWHs, and it is still producing 197 watts at 5:20 pm. The DC panels have made 2,744 watt hours, and it is still making almost 50 watts. All of that 2.7+ KWHs from th DC panels went straight into the batteries. When you take the house load from the Enphase production, that leaves it putting 7.9 KWHs into the battery bank. So I stocked up over 10.5 KWHs to use this evening, even with the clouds. That is a bit lower than a good day, when I can store as much as 16 KWHs, but it's not bad.
 
those rates are HUGH. I knew their rates where awful, but you are the first customer I have seen share the prices. Just wow

My first 1,000 kwh from the grid is 9.4 cents and over 1,000 is 10.5, no TOU at this city owned power company. Small city in utah
but I usually consume some 20 to 30 kwh per month, as my electric range/oven is the only thing on grid and when my battery is fully discharged and the grid does the backup operation
 
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I never exceed the baseline credit, so I like their new way of showing it on the bill. My rate is actually the lower cost rows.
Don't forget when you generate more then you use, the baseline credit will become a COST (negative x negative = positive)
eg my tracked charges:
Screenshot from 2022-11-02 19-32-51.png
This is just for transport, I use CPA as the generator for electricity
Luckily I have a buffer ;-)

Screenshot from 2022-11-02 19-39-34.png

My new winter rates:

Weekday Winter Rates:
Off-Peak: 39 cents from 8 a.m. to 2 p.m., and 8 p.m. to 10 p.m.
Super Off-Peak: 18 cents from 10 p.m. to 8 a.m.
On-Peak: 48 cents from 2 p.m. to 8 p.m.

Weekend Winter Rates:
Weekend Off-Peak: 39 cents per kWh from 8 a.m. to 10 p.m.
Super Off-Peak: 18 cents from 10 p.m. to 8 a.m.
 
In just 1 month, you Exported 1.8 Megawatt hours of energy out to the grid! Wow. That is on top of what you actually used. My entire PV solar array in perfect conditions will fall under 1 megawatt hour of total production in a month, and my total for a year is only 8 megawatt hours. How many watts of solar panel do you have? Assuming you are getting a similar amount of sun as I am, you must have over 14,000 watts of solar panels.

Yes, I saw the "Baseline Credit" as a charge when my month total was negative, but when I looked at how it is calculated, it makes sense. It is a discount off of the electric rate when you use less than a certain "baseline" amount. I still have not been able to find what my baseline limit is, but I think it is about 200 KWHs a month. Might be a little more. What that means is if I consume 40 KWHs at peak time, I am initially charged 47 cents per KWH or 40 x 47 = $18.80. But then they credit me at 9 cents per KWH so 40 x -9 = -$3.60 So the total for that bill would be $15.20 or the same as if they had just charged 47 - 9 = 38 cents x 40 = $15.20 Now when you over produce and get a credit, it has to do the reverse. If you send them 40 KWHs, they credit you $18.80, but then have a charge of $3.60 so the end result is a credit of $15.20 for the exported 40 KWHs. So yes, it does look funny to see a credit turn into a charge, but I see why it is like that.

Here is the same portion of my bill. It looks like you ae on the EV "Prime" rate. So you have the cheaper charging time, but then a more expensive and longer peak rate time.

SCE-charges-Oct22.PNG
This is my first month of a new year.
 
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In just 1 month, you Exported 1.8 Megawatt hours of energy out to the grid! Wow. That is on top of what you actually used.
Yep, and I try and do everything electric.
EV driving, heating, cooling, cooking etc.
My entire PV solar array in perfect conditions will fall under 1 megawatt hour of total production in a month, and my total for a year is only 8 megawatt hours. How many watts of solar panel do you have? Assuming you are getting a similar amount of sun as I am, you must have over 14,000 watts of solar panels.
I just pushed 17.1kWh back into grid between noon and 1pm ;-) I have about 21kW DC installed atm.
Yes, I saw the "Baseline Credit" as a charge when my month total was negative, but when I looked at how it is calculated, it makes sense. It is a discount off of the electric rate when you use less than a certain "baseline" amount. I still have not been able to find what my baseline limit is, but I think it is about 200 KWHs a month.
From SCE:
Each customer has two baseline allocations, one for summer and one for winter usage. Baseline allocation is the same as the baseline allowance found on the standard residential rate plan. Your allowance can be found by reviewing the “details of your new charges” section of the bill statement. Under “additional information” you will see your summer baseline allowance, your winter baseline allowance, or both, depending on which month’s bill you review.

I am in baseline region 9, so 16.5 kWh daily allocation

Might be a little more. What that means is if I consume 40 KWHs at peak time, I am initially charged 47 cents per KWH or 40 x 47 = $18.80. But then they credit me at 9 cents per KWH so 40 x -9 = -$3.60
Imo: the kWh is 1:1 but you always have a transport part from the grid to you of about $0.028/kWh
So the total for that bill would be $15.20 or the same as if they had just charged 47 - 9 = 38 cents x 40 = $15.20 Now when you over produce and get a credit, it has to do the reverse. If you send them 40 KWHs, they credit you $18.80, but then have a charge of $3.60 so the end result is a credit of $15.20 for the exported 40 KWHs. So yes, it does look funny to see a credit turn into a charge, but I see why it is like that.
My true-up (annual bill) is in may of each year.
My april 2022 SCE bill showed this:
Screenshot from 2022-11-03 15-20-48.png
This is what was mentioned on my May SCE bill
Screenshot from 2022-11-03 15-22-29.png
In red what they paid me with a check.
$341.69/7911.247= $0.0432/kWh of surplus energy.
Minus the $230.77 that SCE billed me during those 12 months I netted a whopping $111
No natural gas used, I still do have a gas pickup for my business but the Lightning is ordered, delivered Q1 23. Then I will be fossil fuel free.
 
Yup, you have nearly 4.5 times as much PV Solar panel than I did. I added 1 KW of DC panels, and may add another 1 KW soon. But even then, I will only have 6.8 KW of raw STC panel rating. That is just under 1/3 of your system still.

So my annual true up was still a charge. It was about $1,000 the first year, so I got it changed to bill me monthly. Credits still build up, and if I end up with a credit balance, they will roll it to the following year unless I ask in advance for a pay out. Otherwise, the credit just pays for the following month. Before I added the DC panels, I still had to pay a bit for several months. With the extra 1,000 watts, I zeroed an additional month, maybe 2 or even 3 by the math. With 2 KW of DC panels, I just might net out below zero for the year, until I get a plug in car. Based on the performance I have been seeing from the DC panels, the 1,000 watts I have now should end up producing close to 1,500 KWHs in a full year. Doubling that with another set of panels should do the trick.

Yes... Even with the 1:1 credit for the exported power, they still hit us with charges we can't recover. That is why I am trying to make as little power as possible go out and back in through my SCE Power Meter. I do my best to only export extra when I won't be needing it later. I put as much as I can in the batteries, before allowing export past a few watts.

I still can't find my actual baseline amount. I have looked all around on the SCE web site, and read through all that stuff about where to find it. The map they have online has poor resolution, I could be in region 9 or 16. Might be opposite sides of the road, can't tell. Here is that "Details of your new charges" section of my bill...
SCE-details1.PNG
Under "Additional Information" where it should be, it is not listed. Since I am exporting less than 3 KWHs a day, and hardly importing at all, I know I am not even close to the "Baseline Allocation" but it would be nice to know what it is.

I see how they are at using up the NEM credit with all their little charges. I had several months where I averaged exporting every day, and still ended up having to pay a little. I know I am not going to ever make money, but I am really trying to just make it go zero. But I don't want to do it by exporting a crap load around noon. That is the big excuse they are using for the new NEM 3.0 rules to screw over home PV Solar customers. I am minimizing my effect on grid stability and both pushing and drawing as little as possible. If every house did what I am doing, it would vastly reduce the demand on the existing grid. I like having the grid there for when I need some power. So if I end up paying a little here and there, I am cool with it. But when they start adding charges because I have a solar panel that does not ever push power to the grid, something is wrong.

I am waiting for someone from SCE to contact me and ask how I am not using any power from 4 pm to the next morning. And why my PV Solar has essentially stopped exporting. SCE does not know I added the battery system, but the bill does make it seem pretty obvious. I did not permit my battery addition, because I can't move my non UL battery out to a separate fireproof building 5 feet from the house. So until I change to a UL rated battery, I am kind of stuck like this.
 
We finally had a good near cloud free day with cool air. The days are getting shorter, and the sun angle is too low for my panel angle, but this is a good average Fall day here.
This is what the Enphase solar did.
Enphase-11-03-22.PNG
Producing 21 KWHs out of 4.8 KW of panels is a decent 4.375 sun hours. And that is the AC output after the Enphase inverters. Production that day before was weak at just 14.4 KWHs with the clouds, you can se the line graph where production was down in the morning and afternoon. The result was that the battery bank did not reach full charge the day before, and it ran down to the 5.1 volt cut off just 15 minutes before the sun was able to take over. Here is what that looked like in the XW-Pro.
XW-Batt_11-03-22.PNG
At 7:52 am the inverter went into standby so I used grid power until the battery voltage came back up at 8:02 am. But that was not the Enphase panels. That was the DC charge coming from the NewPowa panels and BougeRV charge controller. The voltage only went up 0.04 volts, but it too the XW out of standby and it helped run the house as the Enphase solar started making some power as well, but not enough on their own. This is one of the first times I have been able to see this happening. The DC panels and the AC panels are working together, driving the loads in the house to keep the grid current at zero. It is not until 8:49 that the Enphase panels alone are making enough power to run the house and have some left over to start charging the battery bank. I see the 7 amp charge start up and the battery voltage starts to climb faster. With both the BougeRV charge controller and the XW in charge mode, the voltage climbs pretty quick. The battery bank ends up getting fully charged to 57 volts at 2:13 pm. The XW goes back into standby, the Enphase inverters are powering the house completely, and the excess AC production is being exported to the grid. At the same time, the BougeRV charge controller is still pushing 10 to 12 amps into the battery bank, but we can't really see any of that here. But the JK BMS does show the current coming in and the voltage did still go up about 0.06 volts. Here is what SCE shows for the consumption this day.
SCE-11-03-22.PNG
Since the battery did run out, there was a little grid consumption in the 7 am to 9 am area, but it never even reached 200 watts, so the total was easily exported back once the sun did come up. MY small 100 watt export went for 4 hours as the battery charged, then the 2 pm, 3 pm, and 4 pm hours see the extra Enphase energy export. Then the house ran on battery all the way to the next morning, and this time, since the battery was full, it did keep going until the sun was up, and never used any grid power.

The end result was another day of net export. In this case, it was 3.23 KWHs of export total for the day. Here is the fun part. Without the 1,000 watts of DC panels, I would have had to consume grid power on this day. The BougeRV controller did this..
Screenshot 2022-11-04 at 10.51.50 AM.jpg
That shows it pushed 3.602 KWHs into the battery bank on this day. Slightly more than my total export to SCE. Without this extra energy, I would have fallen short. And that is exactly what I see, day after day last year. Just that extra 1,000 watts is making the difference between NET export and NET consumption. As the days keep getting shorter, it still won't be enough. The plan is for another 1,000 watts of panels. That should keep me as a net exporter all winter.
 
those rates are HUGH. I knew their rates where awful, but you are the first customer I have seen share the prices. Just wow

My first 1,000 kwh from the grid is 9.4 cents and over 1,000 is 10.5, no TOU at this city owned power company. Small city in utah
but I usually consume some 20 to 30 kwh per month, as my electric range/oven is the only thing on grid and when my battery is fully discharged and the grid does the backup operation
Electricity rates are a hidden tax here in the People’s Republic of California.

State has a virtual monopoly on power distribution.

State sets the rates.

State decides who cannot afford the inflated rates and should qualify for discounts to bring net rates back closer to rational levels.
 

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