So far so good Jan, glad you are doing this.

When I was installing and upgrading and repairing off-grid home electrical systems in Hawai'i, I was explaining this stuff constantly, at this basic level. Plus all the issues of off-grid systems...

Most people have no understanding of how much power a 'normal' industrial world home uses, or how much of it is 'hidden' use.

Speaking of which, a few comments on your two categories:

1) many "occasional" devices actually use some amount of electricity 24/7/365, if they are plugged in, even if people think they are "off." These are called "ghost loads" and in a "typical" house they can add up to quite a bit of usage. TVs, audio equipment, computers, printers, stoves/ranges, just to name a few, and anything that has a display that is on even when the device is not "in use."

2) some "permanent" devices do not use electricity 100% of the time. Refrigerators and hot water heaters are the two biggest examples. They turn on, then off, then on, then off...to maintain some internal temperature. Though of course nowadays most refrigerators have displays and digital controls and other circuitry that use "ghost load" or greater amounts of electricity constantly.

I am guessing you know this and are leaving it out for simplicity, and the numbers you use will account for it. Most "permanent" appliances with less than 100% duty cycle are rated on an average over time so the data for those will be accurate..

Also I appreciate that you will go into the non-negotiable needs of the grid systems we have - base load and so on. Almost everyone knows nothing about this, but it is crucial to understanding how non-fossil sources can or cannot work with our grid systems.