Water was a scarce resource and probably doesn't count as renewable. There wasn't much need for solar power since it seems they had better energy sources. Spice was mined and used without consideration for its replenishment.
Herbert was vague about some of the technology used, that I know of. Water collection was kinda the biggest thing.
While the Fremen respected the desert and lived in it, I don't think it really has a comparison to a solarpunk society. Fremen only learned efficient ways to survive, IMHO. By that, I mean they learned ways not to get eaten or get extremely dehydrated. It's a bit more of "living on the edge" with scarce resources.