$912 Energy Independence Without Red Tape

But I used the highest gauge I could find! I looked hard, but I couldn't find any with more than 16 ;p

I think this could be considered intentional, because in most countries, connecting this inverter to anything (source, sink) would require certification (+tests), as it doesn't have standard electrical outlets (it varies from country to country, but in the countries I've seen, either certification is required or connecting wall/ceiling lamps is exempted from this, but verification must be done afterward).

Yes and no; it really depends on what kind of house you have, how many people live there, and (culturally?) where you live.

I have an 1800 sqft condo in San Francisco, and a 3.6-4.0kW solar system would be what I'd end up installing if I were to do it the "normal" route with an installer and all the "red tape". Yes, that's obviously 3+ times the 1.2kW demonstrated here, but even a system like that would be useful for me to reduce my electricity costs (especially given where I live).

I know people with more modest electricity needs than I have. I also know people who have 16kW of solar on their roof and that still isn't enough to avoid pulling power from the grid sometimes. So: yes and no; it depends.

I never planned & priced out battery storage, but, sure, 2.4kWh would be pretty low for my needs, but it would still be useful.

It's just weird that the article title includes the phrase "energy independence", when the author admits that they still pull more than half their usage from the grid.

This is also a pretty bad outcome.

Generally speaking, you're just not supposed to do permanent electrical wiring with extension cords and power strips, especially not for stuff that goes into or through walls. This has nothing to do with plastic - you have plenty of plastic in electrical boxes, outlets, PVC conduit, etc. Cable insulation is plastic too.

The electrical code doesn't want you to put extension cords in the wall mostly to make sure that the connections can't come apart, that the comparatively softer and more delicate wires aren't easily crushed or abraded, and so on.

This project definitely isn't done the way you should do it if you had a real budget dedicated to it. Is it a death trap? Meh, I've seen far worse extension-cord contraptions in US homes.

Otherwise said renter will quickly find themselves in violation of most lease agreements for creation of hazards on the property.

10awg single conductor THHN can handle 50 amps but when it's in NM-b (house wire/romex) it's 30 amps.

Extension cords can get really hot as they often have the conductor insulation, some packaging material for support, and the outer coating. It also greatly matters if it's 10ft vs 100ft due to resistance.

I've seen extension cords that were used for ACs melt carpets

Agreed, a long run adds so much impedance that during a short circuit, the breaker won't trip instantly. It will just sit there and let the fault current cook the wires.

Various jurisdictions require a fault loop impedance test for installations (and discussed one looks "fixed"). This cannot be eyeballed from a wire diameter table, must be measured.

But once you get something going, go back, apply all your learning (because you will have learned a lot), and do a little cleanup. Especially if it’s your own personal DIY project.

Cleanup does take some time so budget it in.

My first solar project initially looked like a mess of wires like OP’s, although confined to my workbench. But after I got it working, I calculated all wire gauges, put fuses and breakers everywhere, and put the right type of wires in the right type of conduits. As it had to transit a living space, I also made it look nice — you didn’t see a single bare wire anywhere — definitely no 2/0 cable running up a wall.

You could also look at it as craftsmanship.

If you were writing pieces of self driving code or were building a wooden chair for yourself to sit on, that change up things a bit. The most fundamental distinction isn't in whether it's hardware or software, but whether it's safe or not.

Buy a customer-oriented device instead, if you can. I vaguely remember there are plenty of them on the market with built-in batteries. They should have RCD/GFCI and overcurrent protection (and thermal, and BMS included) per outlet (or per bus).

If you want to stick with your current inverter, here are some thoughts from first principles:

- ground it while using, but this might be hard at a remote camping site (maybe use a grounding rod?). If it's a similar model to the one in the article, it must be grounded.

- a GFCI/RCD rated for 30mA or less with 15-20A circuit breaker (I'd suggest type-A if in EU) that matches your wiring and outlets.

There should be ready-to-go boxes that provide RCD+OC, and maybe you're already using one.

The 20A is not being "enforced" in any way and your outlet can receive, and pass on, any arbitrary current ... until something melts, that is.

You could achieve your goal by wiring in a fuse, or circuit breaker in that circuit and could probably nicely (and safely) package it up in a plastic junction box, etc.

It’s “not required” in the sense that it works. Poorly. Have you contemplated how balancing between paralleled “12V” LFP packs works? LFP has a voltage vs SoC curve that is very unpleasantly flat for purposes of cell balancing without intelligence, and almost no intelligence is available in these arrangements.

> Theres nothing wrong with 12V setups (see all the RVs that are out there).

There is so much wrong with them that it’s hard to even know where to start.

Let’s suppose you have an RV-like setup that is designed to power one single 15A 120V receptacle. That’s 1800W, which is pretty small by the standards of modern inverters. It’s also 150A at 12V. Want decent efficiency? That means you want to lose less than, say, 2V on the wires, so you need to carry those 150A over a round trip resistance below 13.3mOhm. If you use the ABYC ampacity table, that’s 2AWG or larger wire. Fortunately 2AWG will carry 150A a respectable distance without excessive voltage drop.

Now, 150A is a lot of current. 150A will make massive sparks, light things on fire, and weld sizable pieces of metal even if 12V is unlikely to electrocute you. And you’re feeding that wire or bus in multiple places (because you may have multiple batteries and a beefy charger), so you remember to put giant 150A fuses or breakers at all the feed locations, right?

But wait, 12V needs below 0.08 ohms to produce 150A. Want to comfortably blow a 150A fuse? You need well below 0.08 ohms total resistance in the entire circuit, including the fault. If you have a high resistance fault (and “high” could be 70 mOhms!), you will never blow the fuse and you can produce literally kilowatts of heat. Crispy! (Your house likely has circuits bigger than 150A, but it’s at a voltage that can much more easily trip the breaker, and in civilized countries there will be some sort of RCD as well.)

Oh, and that 2AWG cable is expensive, hard to bend, and requires actual skill to terminate well. And modern systems often target powers well above 1800W.

At least in a car, the high current portion of the 12V system is made and tested in a factory. And it still makes amazing showers of sparks if anyone messes up a jumper cable. There’s a reason that car makers want to move away from it.

So I stand by my claim: 12V sucks.

Everyone speaks with such confidence that it seems like they know what they're talking about. Then they starting talking the same way about something you're more familiar with and the illusion is quickly shattered.

https://en.wikipedia.org/wiki/Gell-Mann_amnesia_effect