Paulo Baciagalupi is also worth looking into, his book The Water Knife is not explicitly solarpunk either but does deal with resource scarcity and the maladaptations a capitalst world will make to it. He has an excellent short story in the book Rewired: The Post-Cyberpunk Anthology called The Calorie Man which is in the same vein. That is an amazing book on it's own, there are a number of excellent stories included.

Unfortunately I don't know if I've come across any books with the inherent hopefulness of solarpunk, but I would love to read them.