There are some oil reserves in the Baltic and there's a reason the EU is very interested in getting Ukraine on board (Black Sea oil), but frankly, it's more likely we'll just buy it from somewhere else once fossil fuels have been phased out.

Until now there's been over-investment in renewables, but too little in modernizing the power grids. The result has been windmills being stopped during production peaks, because there's nowhere to send the power.

I'd guess investing in grid upgrades, storage and cheap baseload capacity will be the main focus for the European energy the next 20 years.