• 31ank@ani.social
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    3 months ago

    You can get a 800Wp (max allowed Wp for a balcony solar) kit in austria for around 500€, germany is currently limited to 600Wp so it should be about the same price or cheaper. And you just need to plug them into a schuko outlet, so most people should be able to do it themselve.

    Edit: Fixed units

    • kELAL@lemmy.blahaj.zone
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      3 months ago

      I felt a great disturbance in the Force, as if thousands of physics teachers suddenly cringed and started yelling “Get your units right!”.

      spoiler

      Wh is a unit of energy (1 Wh = 3.6 kJ) and by nature cumulative. And cumulative units can’t peak, so Whp [sic] is impossible as a unit. What you really meant is Wp, as W is a unit of power (1 W = 1 J/s), which is a momentary value and momentary values can peak.

      • 31ank@ani.social
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        3 months ago

        Luckily I’m not in school anymore xD

        But thx for correcting me, edited my post, should be correct now :)

      • elrik@lemmy.world
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        3 months ago

        I’m sure the original comment had incorrect units as used, but this explanation that cumulative units “can’t peak” seems wrong.

        If you consider the total stored energy (Wh) over time of a solar-battery system under load, there certainly will be peaks or, in other words, maximal excess capacity of the system.

        So no, it’s not impossible to define a unit of Whp as such. “Cumulative” and “momentary” values are not exclusive and also do not have any bearing on whether a function of such values has maxima and minima.

    • barsoap@lemm.ee
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      3 months ago

      New VDE recommendations say 800W on Schuko is tolerated. Wieland is of course better. That’s btw not solar panel capacity but inverter capacity, you can have 2kW on your balcony as long as you’re not feeding more than 800W into the net you don’t need any permits no need to contact your utility no nothing.

      What you should pay attention to as a renter without already existing balcony outlet though is your landlord: They generally don’t like it when you drill holes through exterior walls, window frames, whatnot. Use window feed-through cables (for the PV connections, not the 220V), or dish out (quite a bit) of money to have it done properly (after talking to the landlord). At which point yes you want a Wieland outlet they’re maybe 20 bucks, what’s going to cost money is the electrician.

      • Aceticon@lemmy.world
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        3 months ago

        If you have an outside light on your balcony, you can probably feed it through there, though I’m not quite sure how power coming from inside the circuit interacts with the internal circuit breakers - lights sockets are usually not in the same internal subnetwork as wall sockets and this method would be feeding the power into the first circuit which is usually were all your lamps are, not into the second which is usally were all your appliances are, and it’s quite possible that the circuit breakers for the lamps’ circuit triggers with less current than the one for circuits meant to drive things with much higher power draw like vacuum cleaners, ovens and washing machines.

        • SkavarSharraddas@gehirneimer.de
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          3 months ago

          Modern meters take that into account (and you’ll get one by the energy provider if you don’t have it already when you tell them you installed such solar panels), everything that’s used in your home gets balanced against what you produce, regardless of which specific circuit uses / provides energy. (Only immediate usage though, and if you add a battery that can save your excess energy instead of feeding it back into the grid you roughly quadruple the cost so that’s quite a bit more expensive.)

          • Aceticon@lemmy.world
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            3 months ago

            I’m not thinking the main circuit breaker or the meter.

            Were I live appartments have a whole board of smaller circuit breakers once for a different circuits inside the appartment - for example there might be a circuit just for illumination, another for kitchen wall plugs, a different for bedroom wall plugs and so on, and for each of these there will be one such small circuit breaker.

            These small circuit breakers normally have a lower trigger point than the main circuit breaker, though they might be different depending on the circuit since different kinds of things draw different amounts of power - i.e. household lamps aren’t going to be drawing 1000W whilst an electric oven or electric heater might very draw that or more power.

            In a normal situation, the current comes from the outside, through the meter and the main circuit breaker and then gets divided based on demand and goes through each smaller circuit breaker and feeds whatever is drawing power in those circuits.

            If you have a balcony plug-in solar power system there, wired to any circuit, IF the power does come OUT from that circuit (I’m not sure, though it makes sense it can) and into the other circuits, then wouldn’t the trigger point of the circuit breaker for that circuit (which as I said is lower than the main circuit breaker’s) be important?

            If I remember it correctly circuit breakers are electromechanic and don’t really care which direction the current is going (so OUT or IN is all the same) just how much of it is passing through, so the current going OUT instead of IN on one of those circuit breakers would be fine, but even that being the case, it might still be a problem to wire the solar power via the circuit for the illumination rather than the circuit for the wall socked because the circuit breaker for the illumination circuit might have a lower trigger point than that for the wall sockets circuit (because you might connect a 1000W device to a wall socket whilst a 1000W lamp was already insanelly powerful back in the Filament Lamp days and is much more so in the LED Lamp days).

            PS: Your point about “will power come out of my household and how does that interact with the meter and the main circuit breaker” is also important, but I wasn’t even thinking about that since I was thinking about just the difference between wiring the power out from an appartment balcony via the circuit for the outside lighting vs bringing that power inside the dwelling and connecting it to a wall socket and hence a different circuit.

            • SkavarSharraddas@gehirneimer.de
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              3 months ago

              I only know 16 amp breakers (~3600 W), not sure if lower current circuits are commonly used in Germany. In my experience every socket can power devices like a toaster or lawn mower, so they’re all suitable for such solar inverters.

        • barsoap@lemm.ee
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          3 months ago

          Lighting fixtures in adjacent rooms are supposed to be on different breakers, not sure whether that also applies to balconies, not a room as such is it… but I’m no electrician. While I did get an A in electrotechnics I don’t know the VDE norms by heart (nor would I touch the wiring in a breaker panel).

          OTOH it’s perfectly permissible to have outlets and lighting on the same breaker. That’s all to say I wouldn’t be surprised or shocked to find that a balcony light is on a general “living room” circuit.

          I don’t think it matters in practice which phase the inverter is on. If you run the meter backwards with one phase and forwards with another, it should be still. We’re not talking about an autonomous installation, after all, when the external network is down and there’s no frequency to sync to those inverters stop outputting.

          Which all makes me wonder: Why aren’t we mandating that all new installations come with network isolation and points where you can plug in panels, battery etc? The hardware isn’t that expensive and installing it is practically free when you’re doing the initial installation.