I’m not part of a community at this moment (though I want to be again someday hopefully; though that’s only one possible future),
But I remember in Allegheny Crest, they used quite a lot of technology! One of my tasks was to make raspberry pi’s work so they could use them for things 
And they had extension cords to provide light and power for some cabins out away from the main building, and others that were too far away used small sealed lead acid batteries for DC light strings (and another task I did was going to check on them and collect and recharge them at the main building if they ran low :> )
It wasn’t there when I was, but community members also had interest in building solar panels and DC microgrids
They also used Google and other internet collaborative things (like Docs and Sheets) extensively (eg, for keeping track of peoples’ hours they’d done or accumulated)
Other communities I’ve been aware of used extremely little technology, except social media! XD
Even lone individuals!: A moment that changed me: I had a heart attack at 37 – so I went to live in a cave | Life and style | The Guardian
Also there are people (disclaimer: I’m one lol) trying to use much more advanced technology to design things with the intent that actually using them takes much less tech!