3
Pneumatic tubes were used to deliver mail!
(slrpnk.net)
You can read more about the fascinating history here: https://about.usps.com/who-we-are/postal-history/pneumatic-tubes.pdf
Credit: https://hachyderm.io/@miah
More steampunk than solarpunk, but yeah always interesting to read some details about complex but mostly forgotten technology.
Imagine upping the size, running the vacuums on renewables and automating it though. You could distribute farm fresh veggies to the doorstep of everyone in an entire city. I think that'd be solarpunk as hell.