Zero export system without interconnection agreement

[jaggedben]

I absolutely agree that the utility already has to deal with load variability.

But I'd counter that once you add consumer PV into the mix the utility sees increased variability in the context of lower kWh through the meter. So the cost of accommodating that variability has to be carried with lower sales.
...

I wonder how much variability there really is anf the extent to which it matters. Also for solar+storage the utility will often see less variability, at least at times.

But the purpose of the differential rates is to make sure that the POCO stays covered for their infrastructure, yes?

Perhaps, but I would say that's come about by happenstance. It's the easiest way to adapt existing rate structures to DG. But DG really upends the entire thinking behind the rate structures, and they arguably should be overhauled from the ground up.

 

[analog8484]

You may view the grid as a "battery" but that has no connection to reality. Power has to be consumed as created, or stored in a real battery. There isn't a bucket with your name on it containing "your" electrons that they can just pour into your service connection.

Of course it's not a real battery although some POCO's are building out battery farms. It's a logical or virtual battery no more disconnected from reality than aggregated house load reduction as a virtual power plant that has been implemented by some POCO's.

 

[tortuga]

Interesting discussion, the take away for me is if one owns solar generation panels they are your property, and the grid operator of course has a right not to be messed with by your system.
A cafe I go to has a sign that says 'we have the right to refuse service to anybody for any reason' or something more clever. It seems there is no obligation (or legal precedent) to sell your energy to the grid for a bad deal,
therefore
I think there might be a market for a NEC complaint 'DC island system' or UPS or whatever we want to call a 100% non export system. It would have to be 'air-gaped' from the utility source via a DC buss and a battery bank. like a generator install the payback from such a system would not be financial, but neither is buying a yacht..
Cheers

 

[ggunn]

Interesting discussion, the take away for me is if one owns solar generation panels they are your property, and the grid operator of course has a right not to be messed with by your system.
A cafe I go to has a sign that says 'we have the right to refuse service to anybody for any reason' or something more clever. It seems there is no obligation (or legal precedent) to sell your energy to the grid for a bad deal,
therefore
I think there might be a market for a NEC complaint 'DC island system' or UPS or whatever we want to call a 100% non export system. It would have to be 'air-gaped' from the utility source via a DC buss and a battery bank. like a generator install the payback from such a system would not be financial, but neither is buying a yacht..
Cheers

If you do not want to enter into an interconnection agreement with your utility I am pretty sure you can build any kind of system you want as long as it does not connect with their service conductors.

 

[tortuga]

I would be stupid not to interconnect here in Oregon, I am talking about others whom live in areas that have utilities that do not give favorable terms or any terms to solar, in my area the local utility will buy back the solar at almost 14 cents per kWH and help pay for the installation up to $0.40/AC output watt with a maximum incentive of $2,500.
However in these other parts of the country where its a bad deal or a hassle to export solar, there could be a niche 'zero export' product marketed to them.

 

[GoldDigger]

Showing my age but I remember a phone lineman coming out to my house one time and noting that I was only renting one phone but had two phones in the house, and how that was going to be a problem with AT&T. They have their ways.

The easiest way is to measure the current while ringing the line. The series impedance of ringer and current limiting capacitor was pretty much standardized back then. One phone drew one "ringer equivalent" of current. Measure the current to count the phones.
The DC resistance of the phone lines was small by comparison, and the AC resistance was measurable with all the phones still on hook.

 

[tallgirl]

So then the solution is to migrate the price structure to more accurately reflect the cost structure. For everyone, not just solar owners.

They need to call out all of the major costs - generation, regulation, spin and no-spin reserves, distribution, maintenance, A&O, etc. Pick the top 3 or so, merge the others into that, separate on the bill, move on with life.

 

[pv_n00b]

The easiest way is to measure the current while ringing the line. The series impedance of ringer and current limiting capacitor was pretty much standardized back then. One phone drew one "ringer equivalent" of current. Measure the current to count the phones.
The DC resistance of the phone lines was small by comparison, and the AC resistance was measurable with all the phones still on hook.

I remember when you could first buy phones that they had a ring equivalent number and you had to make sure the total of all your phones and answering machines did not add up to more than the number specified by the telephone provider. This was because the phone company powered your phones and could only power so many. On the upside that is also why the phone would work after utility power was lost. Phone companies were some of the earliest adopters of PV to power the battery systems they used. I have not thought about RENs in a long time.

 

[pv_n00b]

They need to call out all of the major costs - generation, regulation, spin and no-spin reserves, distribution, maintenance, A&O, etc. Pick the top 3 or so, merge the others into that, separate on the bill, move on with life.

I've been a proponent of making residential billing match commercial billing where there is an energy charge just for the energy and a demand charge that represents the amount of infrastructure used to supply the service. Then everybody would pay for the infrastructure and PV can NEM the energy charge. It was just easier for utilities to bundle everything together on residential bills before electronic meters were on everyone's homes. The problem with this is that utilities could inflate the infrastructure charge and make the energy charge small to make PV less financially viable. This is the all-you-can-eat energy model as it does little to incentivize reducing energy usage.

 

[analog8484]

Based on some recent conversations it seems that there have been zero export systems without interconnection agreement well before the rise of the more recent portable units. I learned that many RV/boat inverters (e.g. Victron, etc.) have had a "Power Assist" (https://community.victronenergy.com/questions/29128/power-assist.html) feature for quite a while. Basically, the feature allows the inverters to sync up to shore power (much like grid-tied inverters) and produce additional power from batteries to help power loads requiring more power than what the shore power can provide. So, the feature effectively works like an interconnected zero export system. Clearly these systems have been connecting to the grid at various RV parks and marinas without interconnection agreements for years. Now I am less certain as to when an interconnection agreement is required for zero export systems. Perhaps interconnection agreement does not apply to plug-in systems? I don't find any clear explanation in my POCO's interconnection docs.

 

[jaggedben]

Based on some recent conversations it seems that there have been zero export systems without interconnection agreement well before the rise of the more recent portable units. I learned that many RV/boat inverters (e.g. Victron, etc.) have had a "Power Assist" (https://community.victronenergy.com/questions/29128/power-assist.html) feature for quite a while. Basically, the feature allows the inverters to sync up to shore power (much like grid-tied inverters) and produce additional power from batteries to help power loads requiring more power than what the shore power can provide. So, the feature effectively works like an interconnected zero export system. Clearly these systems have been connecting to the grid at various RV parks and marinas without interconnection agreements for years. Now I am less certain as to when an interconnection agreement is required for zero export systems. Perhaps interconnection agreement does not apply to plug-in systems? I don't find any clear explanation in my POCO's interconnection docs.

Probably still illegal.

There are really three questions here:

1) Can it be done in a way that is really hard for utility to tell for sure what's happening, especially if not given a particular reason to send someone out to look at the service in question? Answer: yes

2) Supposing they realize it's there, will the utility care, and how much? Answer: in many cases they probably don't care enough to do anything, but if people started doing it with solar en masse they'd probably care a lot more.

3) Do they have a legal ground to force you to stop? Answer: probably in nearly all cases yes.

 

[analog8484]

Probably still illegal.

Do you mean violation of federal or local laws? I have been looking and have not found any such laws. It would be great if anyone can point out such laws. Violation of POCO rules/policies is more plausible. The reason why I am now more skeptical is because even if there are laws/rules I would like to know how an RV/boat can be compliant. There are thousands of RV parks and boat marinas in the US and many more mobile RV's and boats can theoretically plug in to shore power at any of these places depending on the trip. What would a practical compliance system look like?

These inverters have been around for years and many have UL458 certification and yet no reports of jurisdictions/POCO's disallowing/punishing these inverters have been found through web search. Wouldn't UL have put something in their standards if it's a real safety issue?

Now that I think about it, any inverter that supports grid power input (usually for charging) could technically be in operating parallel with the grid?

3) Do they have a legal ground to force you to stop? Answer: probably in nearly all cases yes.

Assuming there is such a law, if the law has a history of not being enforced in general then it actually becomes less enforceable in courts.

 

[jaggedben]

Do you mean violation of federal or local laws? I have been looking and have not found any such laws. It would be great if anyone can point out such laws.

State level.
For example in California there's this:

Codes Display Text

Violation of POCO rules/policies is more plausible. The reason why I am now more skeptical is because even if there are laws/rules I would like to know how an RV/boat can be compliant. There are thousands of RV parks and boat marinas in the US and many more mobile RV's and boats can theoretically plug in to shore power at any of these places depending on the trip.

But how many have actually installed the equipment you mention? Hundreds? Dozens?

What would a practical compliance system look like?

Probably much like the one for NEM.

These inverters have been around for years and many have UL458 certification and yet no reports of jurisdictions/POCO's disallowing/punishing these inverters have been found through web search. Wouldn't UL have put something in their standards if it's a real safety issue?

No. That's well beyond the scope of the UL product standards. That's like saying 'wouldn't UL have done something if people aren't following NEC article 705?' The NEC and and utility interconnections cover a different area of safety and reliability than UL product standards do, and are enforced by different people.

Now that I think about it, any inverter that supports grid power input (usually for charging) could technically be in operating parallel with the grid?

No, that's disingenuous semantics. Clearly the relevant regulations only apply to generation, not consumption/charging.

Assuming there is such a law, if the law has a history of not being enforced in general then it actually becomes less enforceable in courts.

Perhaps. I don't disagree that if non-export systems were installed en masse without interconnections that it could lead to some interesting lawsuits or political interventions. But don't be naive enough to think the utilities will have no case in court. Not to mention the ability to spend more money on lawyers. Speaking of which, if you insist on trying this experiment, a lawyer who hates utilities might be the appropriate client to install it for.

 

[analog8484]

State level.
For example in California there's this:

Codes Display Text

Thanks for the link but I was looking for something more specific to zero export systems. In any case, the law's explicit intent is to avoid backfeeding so zero export systems would comply with the intent.

But how many have actually installed the equipment you mention? Hundreds? Dozens?

Good question. Based on some quick searches, there are over 11 million RV's in the US (https://www.rvia.org/media-resources) and more than 1 million people live in RV's full time (https://www.washingtonpost.com/business/2018/11/12/million-americans-live-rvs-meet-modern-nomads/) who are more likely to have inverters. The numbers are much higher than I had expected. Also, it seems inverters started becoming standard on at least some RV's in the early 1990's (https://www.irv2.com/forums/f44/when-did-rv-start-using-inverters-and-battery-banks-497651.html). So, I would not be surprised if the number of RV inverters in use would be in the tens if not hundreds of thousands.

Probably much like the one for NEM.

So an RV owner would have to have an interconnection agreement with the POCO for each RV park that he uses? Doesn't seem practical.

No, that's disingenuous semantics. Clearly the relevant regulations only apply to generation, not consumption/charging.

Well, if you look the law you referenced it's not so clear. I think an inverter would be classified by most as primarily an "electric generator" and its charging function is just a secondary function. The law doesn't provide explicit exemption for electric generators used in charging mode. To make it even more unclear, many inverters literally use the same circuit components to generate or consume electricity via dynamic control that can change the mode frequently. It seems the law was written with primarily gas generators in mind so the specific clauses don't work well for modern inverters especially when it comes to zero export systems. If you follow the intent of the law then it seems clear that zero export systems are exempt as they do not cause materially significant backfeeding. However, if you follow the literal clauses then it seems zero export systems would not be exempt. I think more clear laws are needed.

Perhaps. I don't disagree that if non-export systems were installed en masse without interconnections that it could lead to some interesting lawsuits or political interventions. But don't be naive enough to think the utilities will have no case in court. Not to mention the ability to spend more money on lawyers. Speaking of which, if you insist on trying this experiment, a lawyer who hates utilities might be the appropriate client to install it for.

I am mainly playing Devil's advocate so I can have better responses ready for people challenging interconnection agreements

 

[Hv&Lv]

Thanks for the link but I was looking for something more specific to zero export systems. In any case, the law's explicit intent is to avoid backfeeding so zero export systems would comply with the intent.


Good question. Based on some quick searches, there are over 11 million RV's in the US (https://www.rvia.org/media-resources) and more than 1 million people live in RV's full time (https://www.washingtonpost.com/business/2018/11/12/million-americans-live-rvs-meet-modern-nomads/) who are more likely to have inverters. The numbers are much higher than I had expected. Also, it seems inverters started becoming standard on at least some RV's in the early 1990's (https://www.irv2.com/forums/f44/when-did-rv-start-using-inverters-and-battery-banks-497651.html). So, I would not be surprised if the number of RV inverters in use would be in the tens if not hundreds of thousands.


So an RV owner would have to have an interconnection agreement with the POCO for each RV park that he uses? Doesn't seem practical.



Well, if you look the law you referenced it's not so clear. I think an inverter would be classified by most as primarily an "electric generator" and its charging function is just a secondary function. The law doesn't provide explicit exemption for electric generators used in charging mode. To make it even more unclear, many inverters literally use the same circuit components to generate or consume electricity via dynamic control that can change the mode frequently. It seems the law was written with primarily gas generators in mind so the specific clauses don't work well for modern inverters especially when it comes to zero export systems. If you follow the intent of the law then it seems clear that zero export systems are exempt as they do not cause materially significant backfeeding. However, if you follow the literal clauses then it seems zero export systems would not be exempt. I think more clear laws are needed.


I am mainly playing Devil's advocate so I can have better responses ready for people challenging interconnection agreements

I haven’t read all the responses. Just the last couple..

interconnection agreements…

If you produce electricity from your electrical infrastructure onto ours without an interconnect agreement and a PTO document, and we find it, we can disconnect you from our infrastructure without any questions or further discussions.
And it’s legal to do so.
Should your system for some reason or another export to our system and cause damage or death, there will be criminal liability on your part.

 

[wwhitney]

Thanks for the link but I was looking for something more specific to zero export systems. In any case, the law's explicit intent is to avoid backfeeding so zero export systems would comply with the intent.

Section 119075 calls for any generator, other than one designed to operate in parallel with and approved by the utility (i.e. under an interconnection agreement) to be separated from the utility by an open switch. So I would say that a zero export system that relies on CTs meets neither the letter nor the intent of that section--the intent is to provide a more definitive level of separation than that.

Cheers, Wayne

 

[analog8484]

Section 119075 calls for any generator, other than one designed to operate in parallel with and approved by the utility (i.e. under an interconnection agreement) to be separated from the utility by an open switch. So I would say that a zero export system that relies on CTs meets neither the letter nor the intent of that section--the intent is to provide a more definitive level of separation than that.

Cheers, Wayne

That's a specific clause not the intent which is "The Legislature intends to prevent electricity generated by permanent or portable electric generators from backfeeding into a utility electrical distribution system ..."

 

[analog8484]

I haven’t read all the responses. Just the last couple..

interconnection agreements…

If you produce electricity from your electrical infrastructure onto ours without an interconnect agreement and a PTO document, and we find it, we can disconnect you from our infrastructure without any questions or further discussions.
And it’s legal to do so.
Should your system for some reason or another export to our system and cause damage or death, there will be criminal liability on your part.

It could certainly be violation of POCO rules and I am sure there is a legal way for POCO's to disconnect service. But do you have any actual case of doing so? A real case would be great. Given the surprising number of RV's I am pretty confident if you go down to your nearest busy RV park you could find someone violating the rule. And who do you punish? The RV park? It seems such rules are rarely enforced if ever.

 

[Hv&Lv]

It could certainly be violation of POCO rules and I am sure there is a legal way for POCO's to disconnect service. But do you have any actual case of doing so? A real case would be great. Given the surprising number of RV's I am pretty confident if you go down to your nearest busy RV park you could find someone violating the rule. And who do you punish? The RV park? It seems such rules are rarely enforced if ever.

POCOs do disconnect.
About all of them, including us, have an actual case or two where someone has a bootleg system grid tied.
Just because you don’t hear about it or see it on the 6:00 news doesn’t mean it’s rarely enforced.

 

[analog8484]

POCOs do disconnect.
About all of them, including us, have an actual case or two where someone has a bootleg system grid tied.
Just because you don’t hear about it or see it on the 6:00 news doesn’t mean it’s rarely enforced.

That's good but it would be even better if these cases are highlighted in the POCO interconnect docs/web sites for better understanding by the public. I see much more clear info from POCO's regarding service disconnect for non-payment situations.