there’s a fair few people from SE England here and TBH if you stick around I’m sure folk would help out.
used to be my own stomping ground but staying in work meant moving 150 miles away. its now difficult to openly “brag” about having such things or helping out with potentially unlicensed parties. especially as if you are turned over, the cops often seize the gensets and if they are big decent ones apply to the Courts to keep them as backup power for their comms systems, as they changed to digital radios what need way more base stations and thus use more electric.
so you need to make the connections discreetly but it was done just before the net as Dan OOOPS mentioned in another post.
I assume you are in your teens or 20s, and that whatever should happen in your future (careers, maybe even fatherhood) you intend being interested in music/parties for 2 or more decades (or until your ears/body give out). so its worth also researching stuff like smaller scale alternative power sources, low power but loud rigs etc. I am no “hair shirt” environmentalist, I grew up in London and like my gadgets and big rigs high tech and cheap/easy mobility but it was actually outdoor parties what taught me there is a beautiful country and planet out there and one worth keeping in a decent state for each coming generation.
