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Would adding off grid panels trigger change to NEM 3.0 in CA?

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I live in CA (SCE territory) and currently have a 10kw grid tied system installed in 2019 under NEM 2.0.

I realize that adding panels to my existing system would trigger a change to NEM 3.0. I am considering the possibility of adding a smaller off grid system (panels + batteries) to exclusively power my pool and spa. Aside from the question of the economics of doing so, would it also trigger NEM 3.0 for me even though it’s not tied to the grid?
 
I live in CA (SCE territory) and currently have a 10kw grid tied system installed in 2019 under NEM 2.0.

I realize that adding panels to my existing system would trigger a change to NEM 3.0. I am considering the possibility of adding a smaller off grid system (panels + batteries) to exclusively power my pool and spa. Aside from the question of the economics of doing so, would it also trigger NEM 3.0 for me even though it’s not tied to the grid?

While it would require permits, it should not require approval from the Electric Utility, and thus should not trigger a change to NEM 3.0.

That being said, there is basically no way this could make $ sense.

You would be better off adding a much larger grid tied system, with more battery, and moving to NEM 3.0 vs trying to make the pool off grid IMHO.

-Harry
 
I live in CA (SCE territory) and currently have a 10kw grid tied system installed in 2019 under NEM 2.0.

I realize that adding panels to my existing system would trigger a change to NEM 3.0. I am considering the possibility of adding a smaller off grid system (panels + batteries) to exclusively power my pool and spa. Aside from the question of the economics of doing so, would it also trigger NEM 3.0 for me even though it’s not tied to the grid?
It won't, but there are many fewer installers who are willing/able to do off grid. You might want to consider having a charger attached.

Off grid is much more of a DIY thing, but as Harry points out, you will need permits, and one of the biggies in the permitting process is getting the wind load calculations signed off by a PE.

All the best,

BG
 
While it would require permits, it should not require approval from the Electric Utility, and thus should not trigger a change to NEM 3.0.

That being said, there is basically no way this could make $ sense.

You would be better off adding a much larger grid tied system, with more battery, and moving to NEM 3.0 vs trying to make the pool off grid IMHO.

-Harry
I wonder if the day is soon approaching where this could make some sense for very specific scenarios with the right equipment, esp if small enough to be a DIY project. I mean, a single grid-tied Powerwall is still about $15K ($11K after federal tax credit), but pretty much half the cost is for installation since it needs to be tied into the grid and your home loads, so meet many code and safety requirements.

My sister's pool has a small standalone 3' high shade structure to protect the pool pump and filter area from the elements, that I've long wondered whether racking a string of 2-4 panels on it directly to a DC pool pump would provide a decent off-grid solution. But these days, the all-in-one battery systems make it even simpler, and could work with their existing AC variable speed pump.

I've seen Ecoflow's already approaching <$500 / kwh on sale recently, with some Chinese LFP batteriy stations coming down as low as $250 / kwh. These batteries already come with a MC4 connector and solar inverter built-in, and an AC inverter for the output. Most feature passthrough capability, so they themselves can be plugged in to supplement cloudy days with shore power if there isn't enough solar production. Much of the solar production will be directly consumed by the pump during the day, so you only need a battery sized large enough to carry over the excess production at mid-day peak to later afternoon - so maybe 1-2 kwh battery would be sufficient. The variable-speed pump flow could be adjusted accordingly to balance this out, as well as make sure the startup wattage doesn't exceed the battery inverter's surge capacity.

So 3-4 panels attached to a low shed, a 1 to 2 kwh all-in-on battery unit, a variable speed pump, possibly minimal permitting costs...
 
My pool consumes about 3 kWh (<$0.75 if it came from the grid) per day with a VS pump, so any solution would have to be very cheap to make the payback worth it. It might make a fun project though.

Yeah they sell whole kits… looks like you can even install on a purgola if there’s no county or city inspection heh.

 
I posted this on the NEM3 thread. Looks like at least one installer is trying to do this

So there is a guy selling solar telling people that want to add to their solar systems that he can keep them off NEM3 with the upgrade. I guess there are a lot of new house developments where solar was included, but the systems were sized pretty low. Not sure what the rules are for new construction. Aanyway this guy will put in a "standalone" new system and not tie it to the grid so they won't export from the new system. I guess he is putting in solar plus battery and setting it in Off Grid mode. Seems a bit sketch to me and I can't quite picture the wiring since it will be powering the house and the house is tied to the grid. He is NOT suggesting that they could be 100% Off Grid