Ideas needed for World's largest Hackathon [HELP]

I'm participating in the Geeklist's hack4good which is the world's largest hackathon against climate change.
I need ideas for a simple python script which helps in having a positive effect on the environment. A silly example would be, a script to turn off your computer due to over usage.

I really need your help!
Please post what ever idea you have in mind.
Thanks.

Im not sure if it's possible, but perhaps a script to turn off a light if it's been on for a certain amount of time?

Others, more suggestions please!

If you hack me a pony, I'll plant a tree.