Deploying an Arduino Uno R3 standalone I have an Uno R3 with a sensor board and a temperature sensor. I'm running a simple temperature check and would like to store that data outside the Ardunio for keeping records, graphs, etc.

I powered it from my PC during development, but obviously I want something more compact when deployed. It's still inside the house, but I want the PC shut down, not running 24/7.

I do have wireless access, and a Raspbery Pi 3 model B. Can any of those help? Or should I buy an ethernet/WiFi shield and try to get acces with those?
So you would rather use your Raspberry Pi than your PC? Easy, as it
turns out that a Raspberry Pi is not that different from a PC running
Debian or a Debian-like OS (e.g. Ubuntu).

Just connect the Uno to the Raspberry Pi through the USB link. Log the
data on your Raspberry exactly like you would do on the PC. You don't
need any Ethernet or WiFi shield. You just need to make sure that
whatever logging program you use on the PC can run on the Raspberry Pi.
This is most often trivial if the PC is itself running a Linux distro.