It is running a Pi Zero 2 W, and that should run max draw 2.5A@5V (12.5W)[0]. So a Watt hr is using a Watt for an hour. So the question is how many hours continuously you would allow your Pi to run. For 24hrs, that's 24hrs*12.5W = 300Whrs. Just for an estimate, a shargeek is $100 and will give you 24 Whrs[1]. I'm sure you could build your own solution for much better, but assuming since you're asking, I'm assuming this isn't a great option.
So probably a bit more expensive than you're thinking. Especially if you're putting it outside, as you'll need to make the thing more secure from weather. But also the good news is you probably aren't going to actually be pulling those 12.5Ws on your pi. You should probably measure and see.
For solar, I'm not sure especially since you'll need to adjust for your requirements. But there are nice resources that can tell you average capacity, but be careful to note that these will usually show averages and you're going to be significantly affected by seasons in Chicago.
Honestly, I'd get a small battery (like for a phone) and hook it up to an outlet and tuck it away somewhere. That's a much cheaper option. Even if you're "going rogue" with it... the power draw is so little you won't really notice it.
So probably a bit more expensive than you're thinking. Especially if you're putting it outside, as you'll need to make the thing more secure from weather. But also the good news is you probably aren't going to actually be pulling those 12.5Ws on your pi. You should probably measure and see.
For solar, I'm not sure especially since you'll need to adjust for your requirements. But there are nice resources that can tell you average capacity, but be careful to note that these will usually show averages and you're going to be significantly affected by seasons in Chicago.
Honestly, I'd get a small battery (like for a phone) and hook it up to an outlet and tuck it away somewhere. That's a much cheaper option. Even if you're "going rogue" with it... the power draw is so little you won't really notice it.
[0] https://www.raspberrypi.com/documentation/computers/getting-...
[1] https://sharge.com/products/shargeek-170