Well, yes, Scotland has many of the best sites for wind turbine generation in the UK. In all likelihood my country would be able to sell energy and water to the rest of the UK when Scotland finally leaves (I am still certain it will happen in my lifetime).
But are you then implying that once the UK left the EU, all power transmission wires were cut as well? Because I don't see a reason why England wouldn't still enjoy low prices for wind energy even if Scotland were independent -- if Scotland has overcapacity, they'll have to sell at any price anyway to avoid disrupting their power grid.
Besides, the European electricity grid is much larger than the EU, it spans all the way from Ireland to Turkey, and from Finland to Morocco.
One of the major limitations of wind power in England is that new onshore wind farms are very difficult to construct if not totally illegal in England. This is probably part of the reason for the situation another commenter noticed: most UK offshore is currently in England's territorial waters. But another reason is due to shortfalls in the physical interconnection between the Scottish and English power grids. UK must construct additional pylons.
There's also major potential for wind farms in Wales, although it's been controversial since some of the sites are on top of peat bogs or scenic hills.
>Scotland finally leaves (I am still certain it will happen in my lifetime).
Scotland could aim for a Channel Islands-type arrangement where they still enjoy an economic union without an administrative one. That would be similar to the situation that existed before the Acts of Union. Of course, they're quite a bit bigger than Jersey, so it could be tricky.
