While the term "Solarpunk" might be fairly new (at the very least, it was used as the title for an anthology of short stories from a set of writers in Brazil in 2012, Alia Gee self published a novel in 2014, and states that her husband coined the phrase in 2009 after reading an early draft) many authors have been contributing visions of sustainable, utopic futures for some time. Here's a list of some of them.
Alia Gee Edit
Alia describes herself as "Mom, writer, human mic." on her website, and is the author of what might well be the first identifiably Solarpunk novel. Suncatcher: Seven Days in the Sky is set in a 2075 post-climate change, post-pandemic, post-peak oil world, with almost all of the action taking place aboard a fleet of solar-powered energy harvesting airships.
Kim Stanley Robinson Edit
Most famous as the author of the tri-colour Mars series (Red Mars, Green Mars, Blue Mars), Robinson has been deliberately crafting utopias in science fiction as early as 1976. His first series of novels beginning in 1984 (Three Californias) have distinct elements of Solarpunk ethos. The first (The Wild Shore) deals with the post nuclear, environmentally focussed crafting of a new American society, while the third (Pacific Edge) actively posits a pathway to develop our current society into a sanely run, utopic, ecologically sustainable one.