Let's do this.
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@maruno @TechConnectify I built my own 20kWh + 5kW off grid setup, batteries included, for about 2000 euros.
LFP cells cost about 40-100 per kWh, you just have to add a BMS, inverter and some cables.
The expensive part is people. Same goes for the panels; 5kw of panels is 500€, but getting them put on your roof and cabled and all that costs (sometimes tens of) thousands, because there aren't a lot of people who do it and they want a high profit margin.
Happy to show you how to do it though

@anthropy @TechConnectify Simply answered: my house is not off grid nor do I want that. But just getting this professionally done, for sanity but also following guidelines for insurance etc. blows up the costs. Electricians are not cheap to start with.

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@anthropy @TechConnectify Simply answered: my house is not off grid nor do I want that. But just getting this professionally done, for sanity but also following guidelines for insurance etc. blows up the costs. Electricians are not cheap to start with.

@maruno @TechConnectify It's honestly purely the electrician and convenience that really drives up the costs actually!
If you want a grid tie battery it's even easier, you can buy those plug-in ones that you can plug into any wall socket for around 1k, 2.5kwh (random example from the top of google search results: https://www.homewizard.com/nl/shop/plug-in-battery/ ) of course the more easy you make it for yourself, the more you pay
convenience costs a lot of money, especially for these kinds things. -
@maruno @TechConnectify It's honestly purely the electrician and convenience that really drives up the costs actually!
If you want a grid tie battery it's even easier, you can buy those plug-in ones that you can plug into any wall socket for around 1k, 2.5kwh (random example from the top of google search results: https://www.homewizard.com/nl/shop/plug-in-battery/ ) of course the more easy you make it for yourself, the more you pay
convenience costs a lot of money, especially for these kinds things.@anthropy Yeah, I am going to look at one of those however they have the downside that they are single phase. If I am a good boy and register the change I also need to register my current non-certified equipment and that probably won't end well. Plus the inverter is near the end of the life cycle already.
So we are still doubting between doing the legal/right thing of replacing this setup with an inverter/solar combo that is at least on the approved list or just being a bad citizen and take the risk. Going only single phase there are some cheaper options, but cause it causes grid imbalance not something too good and it will not solve our problems of dropout when the grid capacity is exceeded.
Our power company offers as solution for 7000 euro, excl. the needed additional costs for the meter cabinet (which I am definitely not touching and needs full replacement) something.
I do think it is what most people will be looking at as an indication.We will be leaning to something not so 'right' because it's insane, but at the same time my partner works for the grid provider... xD Perhaps his employer might be able to help do it right and chip in (though in exchange for privacy, they want all data then).
It's a messed up situation for sure though that everyone with solar panels will need to navigate within a year. xD
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Let's do this.
@TechConnectify I thought this video was already perfect before the fake ending happened, but everything that followed; Words fail me.
Alec, thank you for saying what you said. It shouldn't need to be you that said it. It's awful that things have become what they are. But what you said is what so many of your fellow countrymen already know. You've given them a voice.
I just hope we don't make the same mistake on my side of the Atlantic.
Stay safe
🇺🇲

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Let's do this.
@TechConnectify Absolutely brilliant and insightful commentary, both the economics and the politics. Well said.
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@f4grx The part that I'm concerned about here is the graphic that seems to imply you can just plug this in to backfeed a wall socket that you'd normally use to plug a lamp or TV into, and that's the part that's specifically dangerous, since you're being a power source downstream of all of the safety systems, and people upstream can't guarantee their own safety from you when repairing downed lines as it works here when you just plug into a random wall outlet with a power source.
@BalooUriza @f4grx Accoring to the new German Norm the Metal Pins on the Plug have to disconnected within 0,1 second and after 1 Second there has to be less then 34 Volts on them.
Here are some pictures wehre we test if a an inverter we had at hand actually does that. Even those exceeding the prescribe times did so just after it.
If the Grid goes down the inverter turns itself off. It has Anti Islanding. No Problem
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@BalooUriza
I might be entirely wrong but as I understand it they have pretty sophisticated current leakage and monitoring abilities and very very quick shut-off. So yes it's back feed but it can detect if something anomalous has happened so it locks out if a breaker is tripped or if a line is cut.
I don't believe you can use these in an outage situation, and you're correct it would be unsafe without an interlock.
@f4grx @balkonsolar@pfriedma @f4grx @BalooUriza Yes a normal Plug in PV sytem is of no use in a power outage. For that you need a system with a battery that can form an island system.
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@pfriedma @f4grx @BalooUriza true, you can't use these in an outage. They don't oscillate themselves, need the grid to follow it (not an expert, @balkonsolar know the details probably). So for danger, the remaining thing is the shape of the plug, with the german "SchuKo" style hiding the pins until the connection is severed, which isn't quite so easy with these flat US-style sockets i guess... There's still discussion about "but what if i really quickly pull the plug out" though...
@derdo @pfriedma @f4grx @BalooUriza yes. Indeed there is a discussion about the time needed for unplugging or otherwise shutting itself off.
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@f4grx The part that I'm concerned about here is the graphic that seems to imply you can just plug this in to backfeed a wall socket that you'd normally use to plug a lamp or TV into, and that's the part that's specifically dangerous, since you're being a power source downstream of all of the safety systems, and people upstream can't guarantee their own safety from you when repairing downed lines as it works here when you just plug into a random wall outlet with a power source.
@BalooUriza @f4grx you are safe if you only plug in a system up to 800 W/ 960 Wp. Stuff above that might make a problem, but generally the wires here should be able to handle 3600 W + 800 W.
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@BalooUriza @balkonsolar no, the panels have a built-in inverter that only works as long as it detects a healthy grid supply. This was specificly designed as a safety measure to prevent backfeeding of disabled circuits.
They are also limited in power to ensure that they can't defeat circuit breakers in detecting overcurrent through house wiring.
(This toot only applies to the situation in Germany)
@nor4 @BalooUriza Right. See for more inof: https://balkon.solar/news/2025/05/28/solar-secondlife-magazine-draft/
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@anthropy Yeah, I am going to look at one of those however they have the downside that they are single phase. If I am a good boy and register the change I also need to register my current non-certified equipment and that probably won't end well. Plus the inverter is near the end of the life cycle already.
So we are still doubting between doing the legal/right thing of replacing this setup with an inverter/solar combo that is at least on the approved list or just being a bad citizen and take the risk. Going only single phase there are some cheaper options, but cause it causes grid imbalance not something too good and it will not solve our problems of dropout when the grid capacity is exceeded.
Our power company offers as solution for 7000 euro, excl. the needed additional costs for the meter cabinet (which I am definitely not touching and needs full replacement) something.
I do think it is what most people will be looking at as an indication.We will be leaning to something not so 'right' because it's insane, but at the same time my partner works for the grid provider... xD Perhaps his employer might be able to help do it right and chip in (though in exchange for privacy, they want all data then).
It's a messed up situation for sure though that everyone with solar panels will need to navigate within a year. xD
@maruno I mean, the companies that actively reach out to market a solution to you, are definitely the most expensive options you can get on the market x3;
If you want it cheap and easy: 3x that plug-in battery as example, one per phase, 7.5kWh total, will cost you ~3k, with zero additional costs, AND you can take it with you when you move to a new place.
But it's up to you in the end, perhaps your partner's employer can help, but the cheap options are not the obvious ones usually.
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@maruno I mean, the companies that actively reach out to market a solution to you, are definitely the most expensive options you can get on the market x3;
If you want it cheap and easy: 3x that plug-in battery as example, one per phase, 7.5kWh total, will cost you ~3k, with zero additional costs, AND you can take it with you when you move to a new place.
But it's up to you in the end, perhaps your partner's employer can help, but the cheap options are not the obvious ones usually.
@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 xDBTW, 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.

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@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 xDBTW, 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

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@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 >.>
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@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.
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@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.
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@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.
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Let's do this.
@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.
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Let's do this.
@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.
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@pfriedma @f4grx @BalooUriza true, you can't use these in an outage. They don't oscillate themselves, need the grid to follow it (not an expert, @balkonsolar know the details probably). So for danger, the remaining thing is the shape of the plug, with the german "SchuKo" style hiding the pins until the connection is severed, which isn't quite so easy with these flat US-style sockets i guess... There's still discussion about "but what if i really quickly pull the plug out" though...
@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...