this post was submitted on 27 Sep 2023
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I can't think of any One-Stop shop for literally everything, but there is a lot of great material out there both on forums and on YouTube. If you take it one step at a time and look at each individual piece of the installation you'll be able to find fantastic instructions for all of them fairly easily.
If you are in the US I recommend purchasing from signature solar, they have a lot of great bundles that will both save you some money and get you everything you need. I'd also say they have the best battery storage options, their rack mount batteries and their new wall mount battery are both fantastic and very easy to work with. They also sell solar panels by the pallet which helps you get a nice large array at a good price.
If I had to pick the hardest part it would just be making sure you get the grounding right on the inverter, if you're not careful it's pretty easy to end up with a ground Loop which isn't particularly dangerous but it will cause lots of weird little issues like flickering lights and other annoyances. But it's fairly easy to correct it it's usually just a result of people connecting both the input and the output on the inverter as well as bonding the secondary panel to the primary panel which creates a ground loop. The solution is as simple as just don't connect to the input power ground to the inverter only connect to the output ground so that it has to go through the ground Bond on the panels
It will definitely sound like a lot, but again if you just take each individual piece by itself it's very straightforward very simple and you'll be able to get it done while saving an absolute asinine amount of money compared to an installer.
I will warn you that if you try to do gridtie, which is where you're able to send excess electricity back into the grid. That comes with a lot more red tape and can get a lot more complicated. I personally did an off-grid setup, which still uses the grid as a possible input so if my batteries are dead and there's no sun out I can still use the power like normal it's just not capable of sending Excess power back out into the grid so there's a whole bunch of red tape that I don't have to worry about.
An off-grid setup with grid power option is still considered a grid tie in my area since it needs a way to prevent backfeeding to the grid. Which is totally doable in several ways, just one additional thing to be aware of.
And as a former solar installer, I also remember looking at signature solar and thinking their kits looked the best.
That doesn't really make sense, since an off-grade inverter literally cannot backfeed. It's essentially just a computer UPS on steroids. It accepts the grid as an input that it can pass through but it's not possible for it to push energy back to the grid
It's 120v, there's nothing to synchronize? Not sure what you're talking about here. Same power is coming from the inverter, battery, grid, generator...
This is standard practice. Inverter - > monitoring - > maybe a knife disconnect - > main panel.
I'm not really sure what you are talking about, you need to synchronize both the phase of the power and the frequency. If they differ even slightly you damage your equipment. This is why when running multiple inverters in parallel they require both a Communication cable and a power sharing Cable in order to ensure that they stay perfectly synchronized. Inverters capable of doing grid tie have equipment in them to monitor the mains power and make sure that they stay synchronized with it. Whereas an off-grid inverter does not contain that equipment which is why they are generally cheaper
There are several different possible phases for 120 volt they are not all the same. And while hooking to the mains may be standard practice for something that can grid tie it is not standard practice for an off-grid inverter. You are specifically expected to have a secondary panel specifically for that inverter. The mains power will reach that secondary panel through the inverter when it's in pass through but the panel should in no way be connected to the mains directly (other than a ground bond between the secondary panel and the mains)
With that having been said, I have no doubt that solar installers have instead opted to continue to use inverters that are capable of grid tie even in a installation that will not be backfeeding. Probably just to reduce the amount of inventory required so that they can get full purchase orders. But that doesn't change the fact that a proper true off-grid inverter is not capable of tying into the mains without destroying itself
The fact that you say you were a solar installer, but you're not even aware of something as simple as phases and frequency synchronization is part of the reason I feel like solar installers are wildly overpaid. You're basically doing the bare minimum without really understanding what it is you're doing
I mean, the other option is you're pulling things out of your ass like every other armchair expert on the internet.
Like...no. You get 240v 2p incoming with a split bar. 120v is 120v is 120v. Maybe you're dealing with 3 phase power but a residential building is not. And I have no idea why you'd have an inverter that outputs 3 phase power in a residential building.
https://youtu.be/NKIbR69opgc?si=kbp9mLaAZ5brQTxf
This is a nice little experiment to show you what happens when you try to parallel two inverters that are not synchronized. Just because the voltage matches does not mean they are in the same phase or synced up with their sine waves. You can also just look at the manual for any dedicated off-grid only solar inverter and they will make it very clear that you are not supposed to hook the output up to the mains panel and doing so will void your warranty and damage the unit. But I'm sure that those inverter manufacturers have no idea what they're talking about /s
Here is an alternative Piped link(s):
https://youtu.be/NKIbR69opgc?si=kbp9mLaAZ5brQTxf
Piped is a privacy-respecting open-source alternative frontend to YouTube.
I'm open-source; check me out at GitHub.