How much electrical engineering knowledge does one need for a solar setup?

How much electrical engineering knowledge does one need for a solar setup?  What are the basics they should know?

This is a really good question.
First off, be prepared  to give up modern conveniences. But this can be good, because you'll appreciate them even more as you build your system.
Ask yourself, could you have been an early pioneer in the early 1800s? Not the romantic ideal, but the actual struggle of a new frontier? If yes, keep reading...

To answer the question, I can describe it in three simple aspects.

(1) Absolutely must have some handyman skills.
(2) Think of it as early horse and buggy days and the car was just invented. One needed to have an understanding of a myriad of things.
Animals had a connection with man, so the two had a symbiotic relationship, both could sense the others needs, the car had no way of communicating, so you needed certain skills for this brave new world.

(3) An congenital/inborn understanding and appreciation of the world around you. In other words, unless you're born rich and can afford to hire someone to do everything for you, stay in the damn city, this is for the person who isn't afraid of any challenge, in fact seeks challenge.

I may get a bit redundant, but only because it's important one understands nothing goes as planned, this is not a perfect system by any means.

Sure, you can higher Tesla to develop a system for you, or another solar company to install a system, but unless you have that indigenous understanding of mechanics, electrical, and chemistry, you have a serious learning curve ahead of you.
One needs to understand how having 10.000 watts on the roof, doesn't really mean you'll ever get that much to use.
There are serious conversion losses, be it through the chemical process of the battery, or friction, the loss through heat, sun and resistance through hotter days, so one may calculate out a toaster, or say pump by reading the running amps/current, wattage draw, but there is startup loss, starting anything drawing a load requires as much as three times the running current draw, though usually brief, it can be a lot.
Say a large draw being demanded while you already have everything in the house running, and your well pump kicks on, a good system can probably deal with it and start the pump, but what if your pump is beginning to fail?

You need to be able to sense the issue, because even though the inverter is rated for say, 7000 watts surge, it is only rated for a short time and if you can't sense the issue, stay home in the city where they supply everything.

One can develop a sense for this, and if you have a natural ability, you'll develop a second sense for your system, you'll develop the ability to know when too much is being drawn simply by looking at the color rendition through the lights, or the weakness of appliances drawing power.
These are things people take for granted when you live on the grid, the power is always perfect, unless it's out.

On solar you aren't afforded such a pleasure. When inverting DC battery battery power to AC there is a lot of things occurring, the voltage is dropping in the battery, the inverter needs to read the voltage and convert on the fly, and the bigger the load, the more the inverter has to work, so you may see a dimming of lights, or an appliance may slow down or act differently.
But create too much of a load, and heat starts to build up, and heat alone increases the load on the system.
Which brings in a secondary power source, the diesel generator. Not gasoline or propane, nope, you'll be lucky to get a 1000 hours out of gas, so spend the money and buy diesel, you'll probably get anywhere from 20,000 to as high as 50,000 hrs, depending.
Depending on what, you ask? Brand, output, maintenance, sizing. If you aren't willing to learn that you will never be able to set it and forget it, that you will always be in a permanent state of maintenance, and this isn't the life for you.

Suddenly the battery voltage drops, the inverter has to work harder and suddenly the lights go out.
"But my Inverter is designed to handle loads like that?" No, it was designed to handle normal loads as long as the battery voltage is maintained, but as you demand more of your system, the harder the system has to work.
Battery voltage vs load, the more load demands more work from the inverter, more work means more heat, more heat means more voltage loss. In other words if you don't have a basic understanding of electricity, this is not the life for you.
So one needs to see this in their third eye, so to speak, you need to make a connection with your new environment and if you don't solar is not for you. (Am I being redundant, on, is this the life for you?)

Cursed as a hyper redheaded kid would be a boon later in life, not the curse I thought it was, having boundless energy finally had a purpose.
I was lucky, every job I had throughout my life was leading to this day, I know, some may not believe in a higher power, but everything I've ever done was a learning experience for the day I would start my life away from the city. All thanks to God, and yes, I've literally lead a blessed life.
Either that, or I was too stupid to see I was being punished. You may have sensed, I'm a total optimist.

I had every job construction had to offer, learned it all and yes, it was all thanks to God. You know what I'm talking about if you've been following these articles.
So venturing into the wilderness was sooo exciting, not scary in the least, and if you have any fear of doing it all by yourself, or trying to prove daddy wrong, stay the Hell home, especially if you don't have the money to do it right, you'll wind up spending more just to survive.

I bought raw land, no neighbors, no utilities, but I had creeks and springs, so that was half the battle. But your every free moment is eaten up by prepping for the winter ahead.
Point being, this will be life here on out, always trying to get ahead of everything just so you can enjoy what you have. There will never really be a moments rest, but that's all part of the experience.
I wanted to know what it was like to actually be a man without the externalities of BS city life, to feel what it was like to face the ultimate challenge of being self sufficient.
Man, those people who set out to conquer the wilderness? They were either crazy, or insane. I'm just nuts, but those men had more balls than anyone I've ever met in my lifetime, and yes, I envy them.

So just know this, if you plan on following my path, you better be a bit a bit crazy and simply not give a damn what others think. They may laugh at you, but it's out of pure jealousy, because if you succeed, you win.
If you truly listen to God, you'll know if this is the life for you. Constantly stay in contact with God, ask for guidance, he won't steer you wrong. If you don't have faith, you won't enjoy the rid ahead.

But be prepared, the challenges never end. Is that the life you seek?
I hope so, I wouldn't change a moment, just wish I had more time ahead to enjoy it all. This was my destiny, my entire life's path was leading to this moment, I hope you enjoy the ride, just remember to stop and smell the roses, or skunk, depending.
Sorry for rambling, but as I wrote, I remembered all the wonderful little moments that all of this afforded me, made me tear up.

Did I scare you, or is this a challenge you're willing to take? If you're second guessing out of fear, then stay in the city where it's safe...