It's not how it's generally used, but In my head canon #eutopia is distinguished from a #utopia by the dynamic change. As a utopia is stagnant unchanging, perfect and final, the eutopia keeps changing. I'm calling #UsrulaLeGuin #dispossessed an eutopia because it was defined by the infinitely burning #revolution within a revolution.
An eutopia might be easier to write because it can have its own 'character arc'. I think this approach can unlock a lot of the #solarpunk creativity. Writing utopia is hard.