Soldato
some countries store their excess by pumping water into a dam then unleashing it to create hydro power.
it's probably cheaper than batteries and less dangerous.
BTW it's not always windy up north and often it's probably too windy anyway
They do it here, lookup power mountain in llanberis, one example, big lake on the top of a mountain, they pump the water up effectively acting as a massive battery, then obviously they can draw the power back out when needed.
Edit: Electric Mountain sorry, not power mountain.