Solar PV power to a specific meter

[Grouch1980]

Hi,
I'm working on a residential building; it will have 4 electric meters... 2 for the rental apartments, 1 for the owner, and 1 for the base building areas (I'm currently deciding if it's allowed to combine the owner meter with the base building meter... is that allowed?).

My actual question is: the solar PV inverter will connect to either the owner or BB panel... the solar PV consultant mentioned that they can talk to the POCO and the POCO has the ability to make sure the solar PV array / inverter output is only providing power to the owner / BB panel. the 2 rental apartments will not receive any power from the solar PV array. Is this possible to do? My impression was that the inverter output would provide power to all the meters. I wasn't aware the utility company can route it to a particular meter. Is this possible by using a net meter for the owner, and the rentals would not get a net meter?

 

[jaggedben]

Let's separate the physics & engineering aspect from the billing & accounting aspect.

The PV can only backfeed the meter it's connected to (unless there are meters in series, but I don't think you're saying that). Once the PV energy passes out through that meter, it will likely go to the other meters 'first' in the sense that if you had another meter upstream for the whole service then that meter would only see backfeed if the PV output exceeded the load of all four meters. However, from the point of view of those other three meters, there's no telling whether the energy is 'coming' from the PV or POCO. (In fact, there's really no telling at all which energy comes from where except in the sense that you can put meters at various locations and determine which direction energy is going at that location for a moment in time.)

So much for the actual physics of power and energy flow.

Now as for accounting and contractual agreements for how to deal with the meter readings, that's all human stuff. Physics does not dictate that any money changes hands, or doesn’t. If the POCO and PV system owner and meter customers and state government all agree that the POCO can credit one or more or none of the non-PV meters' bills for exports on the meter with PV, that's just accounting. It says nothing precise about where the physical energy went, it's just an agreement about how meter readings will be billed for.

Hope that helps.

 

[Grouch1980]

Ah. If I understand you correctly, the solar PV power will go to all the meters (backfeeding the owner's meter, and then going out to the other meters). It's just that, in my case, only the owner will receive any credits or discounts due to the owner having a net meter, and the other rental apartments having regular meters only. Did I follow correctly?

 

[Grouch1980]

Wait a minute…. I’m glad I asked this question, I didn’t know this…. It just clicked I think… the meters where the inverter does NOT backfeed into, those are regular meters correct? So the only net meter is the meter wherever the inverter backfeeds into.

So regarding credits received by all tenants… that’s just a matter of an accounting agreement by all parties? Do I have this correct now?

 

[wwhitney]

Yes

 

[ggunn]

Wait a minute…. I’m glad I asked this question, I didn’t know this…. It just clicked I think… the meters where the inverter does NOT backfeed into, those are regular meters correct? So the only net meter is the meter wherever the inverter backfeeds into.

So regarding credits received by all tenants… that’s just a matter of an accounting agreement by all parties? Do I have this correct now?

Yes. Any energy that is fed back to the utility through the meter that is ahead of the PV interconnection then belongs to the POCO, so it makes no difference to the other meters where it comes from.

 

[Grouch1980]

Great! Thanks everyone.