Oddly enough, buying more wind farms in the same area can solve the power supply issue some of the time. For example, say there is a low wind day when winds farms are not effective enough, but still generating power. If wind farms are cheap enough, one can over provision. This means on high wind days too much power is available, but on low wind days enough is available. This doesn't solve the no wind day, but it does make the not enough wind day less common. And making the not enough wind day less common means the energy storage and generation solutions need to be used less often.

However, having said this, I would like to see a model of this with all the generation potential and costs involved, because right now we are all speculating. One can think of a multi-generation options, with wind and solar being the first and default option, battery (and other storage options) being the next option if wind and solar aren't enough, and gas being the third option if required.

Someone must have created a model like this?