Utopias vs Eutopias
A lot of people like to throw the word "utopia" around, especially where solarpunk visions are concerned. But it's not really a good word to use, for one big reason – a utopia cannot actually exist.
The word utopia itself literally means "no place" because it's a philosophical ideal. In reality, it's unattainable. The reason why is pretty obvious when you think about it. A place which is perfect for one person may not be perfect for another. Ask ten people for a detailed description of a perfect world, and you'll get ten different answers. Some of them may even be horrifying when you consider the implications.
OTOH, the word eutopia (which is a homophone, confusingly) simply means a place which is good. A world does not need to be perfect to be a good place to live in. It may not be perfect, but that's ok. Perfection is a very western ideal anyway.
Basically, if you'll excuse the comic book reference, think Black Panther's Wakanda, not Wonder Woman's Themyscira.
Utopias vs Eutopias
A lot of fiction has been written about utopias, but most of it involves a central plot point when it becomes obvious (either to the audience, or to the protagonist) that this world isn't as perfect as it may first seem.
Think of classic sci fi like Logan's Run, for instance. He believes his world to be perfect until he stops being the kind of person that world was made for. Then suddenly it goes from being perfect to being a nightmare.
Ultimately, no one has the right to impose their version of perfection on others, and you'd resent someone else's vision of perfection being imposed upon you. If you look in that direction, you'll find nothing but colonialism and authoritarianism, and we all know how that ends.
But considering the needs of everyone and trying to build a eutopian world where life is comfortable? I don't think it's too idealistic of me to say that this is an attainable goal.
Not perfect. Simply good.
Creating a eutopia
So where does this leave us? Well, for a start, we should be wary not to reject things which would improve the lives of others purely because they don't fit our internal vision of an ideal world.
Someone on here coined a phrase a while back about not letting the perfect be the enemy of the good. I'm so sorry, I can't remember who that was. If that person is reading this, please tell me so I can give credit where it's due, because I think it's an excellent phrase.
But if for those trying to dream up an ideal world, well... Maybe your friends agree with you. In fact, maybe a lot of people agree with your ideas and visions. But there are 7.53 billion people on Earth. Even among the people you're trying to help with your ideas, there are likely to be some who disagree. Their reasons are their own, and their ideas every bit as valid as yours.
Creating a eutopia
While a lot of people like to talk about revolutions, I'm not convinced that's the right path. Historically, revolutions seem to have just done a good job of moving everyone from one difficult situation into another difficult situation with someone else's ideas at work. There are doubtless exceptions, but there's a big chance of it all going wrong.
My own opinion is that a eutopia needs to be grown like a garden. Carefully and lovingly sculpted, trimming away any diseased or sickly branches, until only the good ones remain. The ones where the sweetest apples grow.
Of course, this would take time. But no garden will grow overnight. And without proper care, even the most verdant garden can fall into decay.
(And just so we're clear, when I talk about diseased and sickly branches, yes I am talking about trimming away things like capitalism, white supremacy, and colonialist thinking. Those particular branches are not even good enough for composting, and should be burned to prevent the infection from spreading.)
One final note – for writers
I've heard the complaint made before that utopian fiction is boring because there's no conflict and that's why dystopian fiction is more interesting. And sure, that's a fair criticism. But replace utopian with eutopian, and that's something altogether different.
To reference Black Panther again (the movie specifically), Wakanda is a good vision of a eutopia. It's a place with fabulous technology, where people live good lives. Their needs are met and, as far as we see, there aren't any systemic problems with poverty or hunger. But Wakanda is not perfect and still contains numerous deep flaws. Those flaws are explored in the story and are the source of every major conflict which happens. At the end of the story, the flaws are still there, but efforts are now being made to address them.
So it's possible to have interesting conflict in a world which isn't a dystopia. If you want to write solarpunk fiction, this kind of eutopia is a good source of inspiration.
Sunbeam City is a anticapitalist, antifascist solarpunk instance that is run collectively.