Enphase equipment readings and accuracy

[foo1bar]

My netmeter reading doesn't correspond to enphase consumption reading. It's probably some strange estimation but I would like to know.

Looking at where the CT is in your box, and the enphase is stating that production == consumption (within ~2kwh), I think the "consumption" that you're seeing in your phone app is really the production as measured by that CT.
Either that - or there's another meter/CT that's measuring just production and it's being called "consumption".

[Wavelet8]

020D73F3-CCB0-4576-B468-08CE17046C3B.pngWell, I still feel it's a calibration or setup issue between the production and consumption reading. On days that I don't generate much solar power, the enphase consumption readings really don't seem that far off from my my hose energy monitor.

[Wavelet8]

In any event, I have the installer looking into it. And hopefully the new monitor I installed will help clear up what's going on. Hopefully, it's calibrated properly, but as tomorrow is going to be cloudy, it may take a few days to verify.

[Wavelet8]

So, I figured out was going on with my solar consumption values. I have a single ct in my enphase combiner box measuring the solar production. I have two ct's In the solar connection junction box. The problem is the placement of the two consumption ct's. They are supposed to be positioned before the solar connection so that they can measure consumption from the netmeter. I have one ct before the solar connection and one after the solar connection. So, one is measuring my consumption from the grid and one is measuring my consumption from the grid and my solar production. See attached photo.

[LPG]

You also may want to ask your installer if the envoy is configured to get the production readings off the micros reported output or the production ct. It's one of the settings on the envoy in the installer section.

[Wavelet8]

I know the envoy is getting its production values from the revenue grade ct. I know that I can purchase access to the micro-inverter output and diagnostic information from enphase at an additional cost. I'm just more interested in analyzing my consumption than production.
Do you feel the information generated from the mice-inverters would be more accurate or beneficial than the single ct in the combiner box and would register a higher output reading for some reasons I'm not aware of?
One of the reasons I believe they don't just give you access to the additional information by default is because of all the additional questions they would have to field as a result. Just my opinion.

[Wavelet8]

So, I'm having trouble attempting to start a new topic so I figure i'll Just add to this existing one. I have a 34 panel LG 360 w panel enphase system. So, simple math 34 x 360w = 12,240kw for my 10 kw output sized solar system in Massachusetts. 10 kw is maximum for maintaining 100% net-metering. Larger system are subject to adjustments to the net-metering ratio by the power company. See attachment:
So, I love the idea of placing the power onto the grid but don't want to maintain a large battery bank onsite since i'm Currently max'd Out per net metering rules. So, i'm Considering the following.
1) adding 7-8 additional solar panels too the roof.
2) monitoring both phases of the output of the solar system so that when I generate 10kw output at peak power I switch the extra 7-8 panels over to a battery bank.
3) when the solar production drops below 5kw at night in the afternoon I would discharge the battery bank back onto the grid.

As far as I can tell, as long as I do not exceed 10kw level of output to the grid I should be ok. I would produce longer/greater periods of output in the morning and night but would not exceed the 10 kWh output level at any period throughout the day.

Does this seem correct or am I missing something?

[Ampster]

............
Does this seem correct or am I missing something?

I assume your new panels will also have Enphase inverters. The Enphase inverters won't work when you switch them off the grid.

Before you go back to the drawing board and come up with another idea I suggest you read your NEM agreement. Most of them are pretty restrictive in terms of any additional equipment that you can add without their permission. The 10k limit is a pricing limit but there are a lot of other details in your NEM agreement that also restrict what you can do. I think it is unlikely that you would be able to add panels and a battery that can discharge to the grid anyway. Most NEM agreements are pretty specific about needing to get permission to change a system that they have approved.

[Wavelet8]

The new system doesn’t necessarily have to have micro-inverters. It might be better to have them as a string with optimizers that way it limits losses between converting voltages for the batteries or used as a supply to a single output inverter to be able to connect to the grid.

The system design will have to get approved and additional controllers breakers,inverters, etc equipment added.

So, maybe I should ask some basic questions first. Before I get too deep into a set process.

1) Has anyone heard of residential customers from mass installing a PV system larger than 10 kw? What was the resulting effect on the net-metering rate? Large or small?

2) Is it true that it doesn’t matter the amount of PV panels installed as long as the system designed output to the grid doesn’t exceed the 10kw output limit?

[Ampster]

The new system doesn’t necessarily have to have micro-inverters. It might be better to have them as a string with optimizers that way it limits losses between converting voltages for the batteries or used as a supply to a single output inverter to be able to connect to the grid.

The system design will have to get approved and additional controllers breakers,inverters, etc equipment added.

So, maybe I should ask some basic questions first. Before I get too deep into a set process.

1) Has anyone heard of residential customers from mass installing a PV system larger than 10 kw? What was the resulting effect on the net-metering rate? Large or small?

2) Is it true that it doesn’t matter the amount of PV panels installed as long as the system designed output to the grid doesn’t exceed the 10kw output limit?

1) I am on the Left coast and the best answer would come from your power provider to find out how much of a haircut they give you on the purchase of power above 10kW. You will need that answer first hand from the source anyway so your assumptions about the economics are correct.

2)That would depend on your NEM agreement. My NEM agreements from utilites in California allow me to add 10% with out asking their permission. I still need to get building permits though.. I don't think there is a solution with micro inverters.but it may depend on the version of Enphase Inverters you have. I have read that they have a modular battery system. If that includes software like my bimodal hybrid inverter and it gives you control over how much you export, you may be able to store the excess for use later when the sun doesn't shine.
If Enphase isn't there yet the only solution I see is a standalone inverter. . That would be expensive and and involve batteries. Depending on the rate you pay and are reimbursed for power it may be a very low rate of return on your investment.

[J.P.M.]

As far as I can tell, as long as I do not exceed 10kw level of output to the grid I should be ok. I would produce longer/greater periods of output in the morning and night but would not exceed the 10 kWh output level at any period throughout the day.

Does this seem correct or am I missing something?

What part, if any, does the long term cost effectiveness play in what you are considering ? Sounds like a pretty expensive proposition for what, if anything, you may gaining in terms of financial cost/benefit.

[Wavelet8]

I guess it’s all how you look at it.
1) I looking into getting a Chevy bolt electric vehicle.
2) My understanding is I can deduct 30% off the cost of a solar electric backup generation system should I loose electric power as long as it’s not tied perminately to the grid.
3) if I utilize the backup storage system to power my electric vehicle with a manual transfer switch it’s a win since i’m Likely charging the vehicle at night.
4) should I loose power due to a winter snow storm I would be able to use my storage battery system w/ inverter to power my house with a
generlink and use the dc charging port on my Chevy bolt as a power wall.
5) power loss in my area is infrequent so when my batteries are fully charged in summer I would want to discharge at least 30 -40 percent back onto grid when i’m Over producing onto the battery system.
6) a small inverter for a 7-8 solar panel system shouldn’t be an excessive cost when compared to the cost and maintenance of an gas/natural gas/propane backup generation system.
7) I should be able to integrate the battery system into my enphase combiner box when the batteries are fully charged or over producing using a small inverter in parallel with my micro inverters.

[Ampster]

Yes it is all about how you look at it. Without more information I can't even tell what it is that you are looking at. Tell us more about the rate structure you are dealing with. You have brought up this concern about overproduction again but didn't answer my original question about how much of an economic haircut you will get. How many kWhrs do you think you will over produce and how much will that cost you? I usually look at the financial pros and cons before I contemplate an idea. Simple Google searches are a good way to test some of your assumptions about cost and feasibility. .
Depending on the answer about the rates you may be able to further rationalize the purchase of a Chevy Bolt by letting it solve your over production problem. Simply charging it during times when you are concerned with over production could be a cost effective solution.

[ButchDeal]

I guess it’s all how you look at it.
1) I looking into getting a Chevy bolt electric vehicle.
2) My understanding is I can deduct 30% off the cost of a solar electric backup generation system should I loose electric power as long as it’s not tied perminately to the grid.
3) if I utilize the backup storage system to power my electric vehicle with a manual transfer switch it’s a win since i’m Likely charging the vehicle at night.
4) should I loose power due to a winter snow storm I would be able to use my storage battery system w/ inverter to power my house with a
generlink and use the dc charging port on my Chevy bolt as a power wall.
5) power loss in my area is infrequent so when my batteries are fully charged in summer I would want to discharge at least 30 -40 percent back onto grid when i’m Over producing onto the battery system.
6) a small inverter for a 7-8 solar panel system shouldn’t be an excessive cost when compared to the cost and maintenance of an gas/natural gas/propane backup generation system.
7) I should be able to integrate the battery system into my enphase combiner box when the batteries are fully charged or over producing using a small inverter in parallel with my micro inverters.

it could be all about how you look at it but some of your concepts are based on inacurate assumptions.
1) ok
2) you get a tax credit on solar equipment regardless of it being connected to the grid
3)if you have net metering there is no need and in fact you would have a lot of power loss charging batteries from other batteries.
4)if you had a bimodal system you would be able to power part of your house (without your car). If you had an off grid system you would be trying some Rube Goldberg type stuff.
5)the power loss frequency makes the other points about backup, rather silly. Why would you want to discharge your battery? You likely are NOT allowed to discharge the battery to the grid as well.
6)an off grid system with batteries is likely much more costly than a genset for similar production.
7) This would require a more expensive bimodal system not a cheap off grid system.

[willow1]

I have a 12.95 kW system in Massachusetts with a Storedge inverter fed by 29 LG 350 panels and a Chem Resu 10 battery for backup only; this is combined with 8 LG 350 panels using Enphase microinverters. This was an expensive but effective way to maximize roof capacity without a second inverter, and get the backup subpanel circuits I was looking for. Netmetering has not been an issue with credits covering my electricity billings to-date.
BTW, I know the Storedge/battery combination was an expensive backup option, but was not able to bury propane tanks for a generator due to wetland conservation issues, and didn't want to run a natural gas line just for a generator.