alt Hacker NewsQuestion for those in the know... See lots of press about balcony solar in Germany, and California recently introduced a bill to allow it (I'm guessing other states already allow it; not sure if the CA bill has a chance of becoming law). But how far are we from a more plug and play home solar system that becomes a primary energy source as opposed to a limited secondary source? And what are the issues with it actually becoming a reality? Is it primarily regulatory where government, utilities, installers would fight it tooth and nail to protect revenue and/or the grid? Is it a legit safety issue? I have to imagine safety could be easily addressed in terms of the power management between grid and solar (obviously these balcony units are relatively safe, but tiny in comparison). Installation perhaps has more safety issues (e.g., installing panels on a roof), but I just wonder if it's reasonable to think that a more robust plug and play option will become available or is even already available in certain places.
And I feel the need to say this, but this is the type of question I'd immediately turn to an LLM to answer, and I probably will ultimately, but I "still" like getting peoples' on-the-ground experience/expertise.
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i think it’s kind of the opposite: balcony solar is good for power companies in the same way that them asking you to turn off your lights is good for power companies: if each customer is using less overall power they can serve more customers with existing infra.
that obviously depends on time of use and the sun etc, but balcony solar in the USA can’t come fast enough. my electricity in NYC is almost $.40/kWh, a limited secondary source is still huge
it makes a lot of sense to me as someone who has casually researched as a way to make the load of an A/C vanish from the perspective of my utility, but i can’t see regulations catching up nationwide soon.
any real microinverters can detect the grid being down and shut off to prevent zapping people working on power lines, but the complexities of split-phase power (you can consume on one leg but backfeed on the other leg rather than consume what you generate, which is bad for billing etc) and risks of intra-circuit overload will all freak out americans.
we put outlets absolutely everywhere because of how scared we are of extension cords, there’s an education and “am i going to start an electrical file” consumer sentiment obstacle to widespread adoption in the US
Regulation aside, a significant issue is physical area. Most people won’t have access to enough area in the right direction to make it a primary source.
It’s primarily a regulatory issue, and more states in the US will approve it over the coming years.
There’s a legit grid stability issue for solar in general, balcony or no.
Usage varies second by second, so the grid relies on physical inertia in the form of rotating turbines. Panels have no inertia; therefore, the more you have the less stable the grid gets.
That is however something which can be fixed by grid-scale batteries. Or home systems, for that matter, if they have batteries and some equivalent of Victron’s PowerAssist.
(Which limits the rate at which power draw can change. Very useful when you use a house-sized generator; it amounts to synthetic inertia. I have a 7kW generator, but a 7kW step load would stall it.)
It can't be more or much more than the 800W as currently done in Germany because it would not be safe with the way electricity is delivered to a home.
The reason is: when you pull electricity from the grid, the fuse would blow if you tried to pull too much current (e.g. you connect four hair dryers on the same outlet). It blows to prevent the wiring in your home from overheating and catching on fire. With balcony solar, you plug it in your home outlet which is already behind the fuse, which means the fuse cannot react and cut off power if you try to feed in more than the capacity allows. You could be maxing out on the current you are pulling from the grid, and then on top of that you would be adding your balcony solar.
Why it's allowed at all in Germany and other places is because the fuse will blow above 10A and the wiring in the house is 16A, so there was always a buffer or overcapacity in the wiring, presumably just in case. So they allowed 800W of balcony solar which is roughly 3.5A and still there is some wiggle room left.
Also why pull from the grid at all: your appliances actually just use the electricity from the grid. In Germany and I guess most of Europe they run a three phase system, so your balcony solar might not be in the same physical circuit as your appliances in use. With balcony solar your meter just offsets your consumption with whatever you are feeding it at the moment. From the grid standpoint if you are running something using 800W and feeding in 800W, it's 0.
Of course it can work without this too, but this defeats the purpose of balcony solar, which is plug it in and it works simplicity.
Utah passed a balcony solar bill; I think they're the only ones so far. Oregon tried in the short session last year, but it got shut down by fire marshall type people, sadly.
>how far are we from a more plug and play home solar system that becomes a primary energy source as opposed to a limited secondary source?
We don't need a more plug and play system. A zero agreement interconnection for whatever UL certified 300W-ish scale is fine and should be widely deployed.
There needing to be interconnection agreements with your utility and an inspection is not a blocker that needs to be removed. Most places require a licensed electrician for complex work, having the electrician fill out a form and having a utility inspection is how things should be.
A standard rooftop solar install with micro inverters is already pretty much plug and play. Wiring it up is the easy part.
Even a more complex system with large centralized inverters and battery backup can be about as plug and play as a desktop computer if you use an all-in-one inverter/charger/controller.
The challenge is scale. You can't take 10kW of solar and plug it into an outlet. It requires more hardware and wiring than that.