I am not sure if maintaining the rate of change is possible. There was a lot of low hanging fruit that is being picked now, but the winter months are not easy to pick.
The current trend for declining cost/MWh for both green production of energy and battery storage of energy is why I am optimistic. It doesn’t look like we’ve reached the declining returns part of a logistic curve yet.
Are you confusing wind and solar? If anything I would guess wind production increases in winter.