Don't mind where it comes from?
If you don't have a preference on where your electricity is sourced from (as long as it's green, of course), that's ok too, just vote for 'any green will do'.
* Tidal has a limited production capacity in Great Britain. At this stage we are unable to commit to supplying a greater allocation of our electricity from this source. We are currently speaking to more Tidal generators to supply more electricity from this source.