See tosfos shabbos 95, “Ve-hurode chalos”, and the maskonoh of tosfos on boneh in yom tov.
We don’t pasken from Tosafos, we pasken from Shulchan Aruch. If you want to see a definitive, clear psak on electricity on Shabbos and Yom Tov, look at Shmiras Shabbos K’hilchoso, at the beginning of chapter 13, where he says that the vast majority of poskim asser electricity on both Shabbos and Yom Tov.
This has been the universally accepted psak for many years.