My system is 10.24kW DC, 7.68kW AC; my array is oriented to 20 degrees west of south, and is approximately at 39N; if I recall it's got a 20 degree elevation - we're set up for best afternoon sun we can get in the summer (by far our peak use time). We have great morning & daytime sun at the location, but get shadowed at latest by 6:45PM in the summer (and much earlier in the winter) because of a tall hill.
I provide the above info about the site because all of that strongly affects the energy production. If your array is on the roof of a house, you're typically constrained to the roof's orientation and pitch.
Here's the pertinent part of my first year's report (system came on-line during Jan 2021, so I left that out, and we're only partway into Dec 2021, so I left that out too):
View attachment 724345
The weather here in the summer is typically clear blue sky with clouds here and there, but almost no "weather"; winter is typically gray and often pretty dark.
August was exceptionally smoky here - enough to drop the local temperatures significantly and undoubtedly affecting solar production.
I'd expect Ohio winter production to be meager with almost any size array.
If you have space, I'd go ground mount, because you're more likely to be able to get as much panel space as you want without having to buy the latest greatest most expensive panels (drop down a tier and buy an extra panel), and there's no chance you're going to compromise your roof by attaching mounts to it.
I used a heavy enough cable between my array and the mains that I can add another 5kW array and not change any components in the system other than a single circuit breaker (I'd have to add another breaker at the array combiner box, plus the 5kW array & mount & cable from that new array to the combiner box - but nothing from the combiner box onwards). I could've *just* put 10kW on my house, but it would've been oriented less efficiently and definitely have no 5kW upgrade path - though there would not have been a 500 foot trench & cable from the array to the mains, either.
Setting up the ground mount is trivial to the typical TBN'er, and gives you some good opportunities to play with the tractor (for footings & cable trench).
Setting up the solar panels and plugging everything together is like playing with legos.
There's a small amount of wiring that some people may prefer to leave to an electrician; I got lucky and the local utility was replacing our local power pole (weather, time and woodpeckers pretty much destroyed it) and had our power out for a few hours and that's when I wired our transfer switch (which involved taking the mains input and sending that to the switch, and attaching the house feed wire instead to the switch); I was going to have an electrician handle that specific task if the utility hadn't intervened so conveniently.
