Can anybody explain how these plug-in solar panels work? I am suprised that it's possible to just plug them in to your wall socket.
For instance, isn't it complicated to have their output be in perfect sync with the frequency that comes in via the electricity net? Because to me it seems that if they won't, you will have lower benefits or even a net minus after plugging it in.
> isn't it complicated to have their output be in perfect sync with the frequency
Not especially, given that the inverter has a microprocessor in it. All it has to do is measure the phase of the existing grid.
I don't have references for how it's actually done, but one obvious approach is simply to wait at each zero-crossing for a new half-cycle to cross a voltage threshold before turning on the output. This also implements the requirement to drop out if the grid goes away. It is probably also possible to measure during the "off" side of inverter output PWM, in the same way that variable frequency motor drivers work.
The micro inverter (most of these balcony kits use micro inverters) uses the grid as the reference. Most of these inverters will actually do nothing when the grid goes down. Like, they shut down for safety so you are not back feeding the grid, but even if you had some sort of back feeding isolation going on, they would still do nothing because they don’t have the reference of the grid.
It’s a downside of many grid tied residential systems (even large ones). No grid = no solar.
The Enphase IQ8 series is one of the first mass market micro inverters based systems to have the ability to make its own tiny electric island when the grid goes down. Requires an isolation switch and a relatively power hungry controller to use that feature, though. I looked into them for a balcony solar setup but it would be way overkill to run a full on controller for 800w of solar!
The best way for a small setup is just have a small “solar generator” battery that can take MC4 connectors as input. Prolonged power outage? Unplug the inverter, plug in the battery.
Not a specialist, just from what I heard: There are two things that make it work. First they are not really "independent" like the title says. They sync with the grid frequency. If the grid is down they shut off for safety. The other reason it works is that the grid power inside the home is just what you get as incoming power 〜230V. For example, I think in the US you get 240V or so delivered to your house, but 120V from the plug.
Syncing them with electricity is easy. The hard part is preventing export to the grid which requires either a compatible smart meter that can communicate with your panels or a transformer clamp installed by an electrician. My understanding is some meters measure both directions equally so if you do end up exporting power you can conceivably increase your utility bill.
We just got rooftop solar in Canada. Our meter was old and had to be upgraded to bidirectional.
We were warned if we turned on the system before the meter upgrade the old meter would sum together power coming from the grid and power going into it from our solar and we would be billed for the combined.
So with some old meters you don’t want to put power into the grid.
You must live in Europe. Not entirely sure but that's the way things are going in North America, as far as I know all the proposed legislation here is zero export. I guess one concern is local grid instability if too much power is generated this way. Also if for example you put a plug in solar on the same circuit as an appliance that uses its power then the breaker doesn't "see" this usage but it still heats up the wire just the same leading to fire risk, but not sure if this has ever been demonstrated or just theoretical. And also there's the old meters still around that don't measure bidirectionally, so those will just roll back or roll forward each way, neither desirable.
I guess if you can solve phase alignment then another big problem is grid capability?
If everyone plugged one in, could the transmission network reliably deliver the power generated where it's needed? I thought that was a serious long term challenge for utilities wrt solar.
Typically, you have "dumb" panels connected to a mppt-controller/charger/inverter box which is connected to batteries and and electrical plug. This controller tunes voltage/current that is taken from the panels, optionally manages the attached battery and measures and feeds into the grid connection.
Some systems are capable of running in isolation from grid (providing 230V AC on their own), but this is less common and often unnecessary.
My understanding is that plug-in solar inverters do sense what is coming from the grid and phase-sync to it with a PLL, and also adjust voltage accordingly.
I can't imagine he's building anything serious. How can you claim otherwise that your agents were deploying code that you couldn't verify. Imagine doing that in any serious business ..
Speak for yourself, I don't ship any code that I don't fully understand. Yes that requires less autonomous AI and less frequent merging.
But I don't even want to think about the disasters that could happen if you really get into the habit of shipping code you can't verify or understand.
Out of interest, what's the speedup between having an LLM write code for you and then having to go through and understand it, vs writing code that you understand immediately because you wrote it?
It depends. If all I want is some prototype or pet code project, my LLM can write most by itself. The speedup could be 10 times or more.
However, if I'd let a LLM write code for my work, I'd have to very thoroughly review it and most likely ask it to rewrite it several times. Each time this would require a new review of course.
There would still be a speed up but I guess at most somewhere around 25%.
In practice I try to combine the best of both worlds. I write some code by myself and rely on my LLM for parts that are not too big and where I expect it to do a pretty good job.
> At some point you're not reviewing diffs at all, just watching deploys and hoping something doesn't break.
Good luck doing that in any company that does something meaningful. I can't believe anybody can seriously be ok with such a workflow, except maybe for your little pet project at home.
So effectively US citizens have been paying an extra tax, which money flowed to certain companies.
I can't wait to hear the justifications that will follow from the Trump government.
This is not entirely true. In an environment driven by business stakeholders, the engineer who ships features quickly, and that break rarely in production, will be greatly appreciated.
The engineer who takes weeks to over-engineer a simple feature, which then runs into unexpected side issues in production, much less so.
The environment where the over-engineer tends to be promoted is one where the engineering department is (too) far separated from where the end users are. Think of very large organizations with walled departments, or organizations where there simply is not enough to do so engineers start to build stuff to fight non existing issues.
This was my exact thought process reading this. The business side of my company does not care or want to wait for complex solutions that sound cool to engineers. If anything, we have the opposite problem: convincing business stakeholders when complexity is in fact warranted.
In my experience, it's the workout itself that ruins sleep when it's in the evening. My theory is that it's because of the adrenaline generated by muscle strain.
For instance, isn't it complicated to have their output be in perfect sync with the frequency that comes in via the electricity net? Because to me it seems that if they won't, you will have lower benefits or even a net minus after plugging it in.
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