Renewables. Sounds good in theory, but what?
Windmills? Only work if the wind is not blowing too soft or too hard and in the right direction.
Solar? The most promising but still very problematic. If peope are serious about this then laws should be passed to force all new builds to have solar panels on their roofs hooked up to the supercapacitors that will gradually fill and run through the night as well (AKA Tesla Batteries) but this will never happen as the energy companies want to sell you all metered power which they will not be able to do if all new builds are off-grid.
Tidal? So inefficient as to be utterly unviable without massive subsidies (kinda like windmills)
Fusion? The technology of the future, and it always will be.