And also because the power is intermittent / can not be planned, you need long distance transmission lines. If you have just coal and natural gas plants, you c

And also because the power is intermittent / can not be planned, you need long distance transmission lines. If you have just coal and natural gas plants, you can throttle them according to usage patterns. If you produce a large portion by wind, it might make sense to build a transmission cable to a nearby country with mountains and hydropower. And there DC is more efficient.