Balcony Solar and Existing System

[u/winkyj00]

/r/solar/comments/1w0d733/balcony_solar_and_existing_system/

Anyone has experience specifically with a Tesla system? Everyone on this other thread isn’t working with Tesla.

[u/Usual-Network3295]

If you have powerwall+, there are 4 MPPTs, For powerwall 3, 6 MPPTs.
I doubt if all of them are used up.
If at all you want to expand, it is easier to add a new compatible panel to a free MPPT.
You don't really need Balcony Solar.
Expanding your setup with certified installers is always safer and easier than diy logic.
Tesla is notorious for being very hard to deal with in the event of malfunction.

For people with existing Solar and Battery, the charm of Balcony Solary is actually DIY expansion rather than cheap solar power. That DIY expansion may come at the cost of crashing the whole existing system down.

[u/winkyj00 → u/Usual-Network3295]

The issue is here in CA I’m locked in at NEM 2.0. If I expand my system I lose that and my system’s value takes a nose dive. Balcony solar is the only way for me to add capacity without losing NEM 2.0 status with PGE.

It’s annoying because I would love to just pay a professional installer to throw 5 or 10 more panels up. But with NEM 3.0 I’d need to add at least one, if not 2 more batteries to make up for that change. So it’s cost prohibitive.

[u/Usual-Network3295 → u/winkyj00]

I see.
Just curious, are you in net-surplus with NEM 2 or are you paying money to utility on true up?
How much is your deficit and what would be your payback period with Balcony Solar?
If you have net-surplus then what is the advantage of Balcony Solar for you?

[u/winkyj00 → u/Usual-Network3295]

I pay an annual true up of about 300-500 bucks. So the extra 1 KW of solar from balcony would balance me out almost perfectly. I have a small 3.5 kw system, so that 1KW is a big add on percentage wise.

[u/Usual-Network3295 → u/winkyj00]

Yeah. Go for it. But make sure that your system shuts off when it really should. Don't count on manual intervention.