Let's do this.

@anthropy I know you mean well, but best to stay with single phase battery instead of plugging in 3 batteries in different phases, still requiring a meter cabinet change and even more difficult and less up to code rewiring keeping a single phase inverter and just pumping power around the house, overloading all cabling. Ahaha xD

BTW, a fixed installation can't be taken with you yes, but it is sort of part of the house value so.

We still got to see, but probably one somewhat larger battery that can perhaps stop most exporting so we don't have to pay is the simplest solution and when we want to use it in the evening the grid is not overloaded anymore would be the simplest solution, even if it's not approved. At least till one of our inverters dies of old age.

@maruno if you have a rather standard digital meter, it SHOULD in theory be possible to just get the state through the P1 port, see whenever you're starting to send power back to the grid, and put that power into the batteries instead.

The battery I linked you actually has a P1 meter dongle you can just tack on for 25€, which should work with a large share of the meters out there.

but again yea, you can do it any way you want, all I'm saying is it neither has to be expensive, nor complicated

@anthropy I know how these batteries work, yes that is how I would set it up. There is still some issues not solved by it though and it's not exactly according to the rules. But yes a lot cheaper

Edit: the only thing not coming from the P1-meter directly though is resistance from the grid when it's overloaded. So it would actually need to store even when I am using energy on a different phase to prevent the solar panels from completely shutting down >.>

@maruno well regarding the "overloading": if you put them on less filled power groups you will not have this issue, and honestly most cabling is purposely overspecced; they want you to use 2.5mm^2 cabling for 10-16A but that can easily carry 27A, as example, and you'll find it's hard to get there.

As for solar shutting down due to grid overloading: the only real option there is off-grid unfortunately, your batteries won't cause the grid voltage to drop enough for the inverters to turn back on.

@anthropy It already is on a overspecced cable, there is something really think going there saying 50A or something on it, but it's not helping much. xD

And yeah, I can put all my energy users on that phase and rewire half my house LOL, that ain't easy either and can cause other issues. There is a reason why this is no longer an allowed setup, with a 3 phase inverter the export resistance is a sqrt3 of a single phase and it doesn't cause grid imbalance. A modern smart inverter can probably even generate more power to one phase based on usage perhaps?

Anyway all expensive solutions with the economically cheapest solution still being to just disconnect the solar panels and perhaps get rid of them is insane. >.>

Off grid is cool and makes sense with all the issues, but also feels like giving up and definitely a bit shady for a city house. All because our government sucked at anticipating the energy transition.

@maruno Off grid doesn't have to be as complicated as it sounds honestly! My inverter is actually a 'bit of both' and can even return energy to the grid if needed.

The main thing you need for offgrid is for the incoming mains, and solar panels, to be diverted to the inverter, and the breaker panel that feeds the rest of the house being connected to that same inverter through a single wire that would otherwise be your mains input. It's basically just 2/3 extra (admittedly chonky) wires.

@TechConnectify So a few clarifications nobody will ever read: 1. Hydrocarbons are dead trees which are renewed but very slowly. The tree is the best solar panel with integrated battery. Just takes say 100.000 years to renew. 2. You cannot replace organic energy with metal energy, because you cannot create metal from scratch without coal, oil and gas; and recycling it is only partly a solution. 3. Nuclear (and fusion) is just boiling the planet with atoms instead. 4. The real problem is food.

@TechConnectify Couldn't do 90 minutes, but plenty of great info. Realistically, if communities don't push their local officials to reserve a chunk of land for solar, instead of selling it off to developers for AI or PUDs, then residents are stuck having to pay the costs individually to privatized money hungry utility companies and opportunists slinging panels.

Separate the grid into a residential circuit (solar) public owned utility and commercial circuit (whatever the fuck they want) privatized utility and the cost won't be so prohibitive for the average person. When the community needs more energy it buys it from the private circuit, when it has more, it sells it back. Individuals all doing this on their own, negates the very benefit of living/participating in a community.

@derdo OK, so can't use 'em in an outage because there's nothing stopping the power escaping the house back up grid... so what's protecting the circuit you're plugging into? Is that also nothing? At least in NEMA world, this would be the case, which would mean it's also a fire hazard and electric shock hazard for the user...

@pfriedma @f4grx @balkonsolar

@sheddi OK, but where's the breaker that guarantees that?

@pfriedma @f4grx @balkonsolar

@BalooUriza
The inverter itself has afi/gfi and a breaker. Someone mentioned the limit is < 5a so it's supplemental to the circuit breaker on the panel.
@derdo @f4grx @balkonsolar

@pfriedma That's considerably less terrifying but everybody is seeing why this just screams unsafe to me right?

@f4grx @balkonsolar @derdo

@TechConnectify Finally got to watch it (okay, half way in but still) - this is a brilliant rundown of the facts. Very, very well done!

/e: Okay, I did not expect that ending. That part was no less brilliant than the techical part. Stay strong over there and take care!

@BalooUriza
Yes and no. If it was just a dumb device spitting out voltage yes but the tech to do fancy safety operations has existed for quite some time. Like, I've seen systems that push kVs through a cable but the instant the supply defects capacitance changes (like from your hand approaching it) the voltage is cut. So a lot less terrifying when you realize what controls are in place. You *can* do these things safely, there are just more factors to consider.

We have a back feed generator interconnect system at home. It has a hardware interlock for the mains breaker to prevent it from energizing the lines feeding the house because its purpose is to run when grid power fails. Within the house, the breakers do their thing, but realistically the inverter is much more sensitive to faults. The last power outage was how we found out there was a current leak in the kitchen, because the inverter alarmed when that circuit was enabled (fixed now) even through the GFCI outlets appeared to be fine on mains power.


@f4grx @balkonsolar @derdo

@pfriedma Yeah, the system my neighbor used was similar but the back feed generator interconnect was to select the locally generated solar and wind resources, fall back to the grid power as a source, or use grid power as a sink, and that was *mostly* automatic, and using contactors. Knowing how that system worked is why I'm looking at this plugin PV and thinking the only saving grace in terms of fire safety is that it's 5A.

@BalooUriza @pfriedma @f4grx @balkonsolar @derdo The entire balcony solar ecosystem seems to run on "trust me, bro": https://akkoma.pikaböl.se/notice/B0R5fpXelwpqdMCPKa
Maybe I'm paranoid, but I'm not letting any equipment designed with an energised male power plug into my home. If you want local generation, you have a professional wire it into the breaker panel with lots of warning labels.

Then again, my balconies face east and west and the sun hasn't been above the tree tops since October, so I'm not exactly in the target market anyway.

@BalooUriza
Yeah the constraint of "at least half as much current as the smallest likely breaker" is doing heavy lifting for fire safety... In the US it would have to be either like 500w or the "plug" would likely want to be a 5-20 to prevent you from e.g plugging a 20a supply into a 10a circuit (though even in this case the inverter could detect a overheat condition based on change in resistance and trip...I don't know that I'd trust just that if I had particularly flammable wires like knob and tube in walls with blown insulation)

@creideiki OK, good, so it's not just me and my NEMA-style wiring idea of electricity that's making me squeamish to this idea, since I need a little more than "trust me bro" on "things that'll kill me faster than an Oklahoma ambulance shows up"

@f4grx @balkonsolar @pfriedma @derdo

@BalooUriza
I think the thing to remember is that the plug isn't actually energized the way you're thinking. It plugs in as a consuming device *first* then "negotiates" then pushes power back. When unplugged it's not still live, it's like you unplugged a TV.
@creideiki @f4grx @balkonsolar @derdo

@creideiki That said, solar's been good enough for long enough now that you might be able to at least cover vampire power with solar with an east-west exposure. I mean, look at the tropical paradise of Portland, Oregon: The light rail trains, rail/foot/road traffic signaling systems and the street lighting on the central transit mall (several kilometers long and two blocks wide, a couplet) is powered exclusively by a single SW-into-a-hill solar array and battery station.