yes, but it's easy to miss external costs of power sources like solar such as the land involved and maintenance (i.e. cleaning the panels to eek out that extra 10%).
Density of power is what matters in the long run. We need a solution that produces the most power for the given space it occupies. Hence, it's not a question of 'if' we use fission, it's a question of 'when'.
This is not entirely true. If solar were super cheap and battery technology were also super cheap and significantly improved from what we have today then distributed solar power (on rooftops, for example) could be feasible. But that's a lot of ifs.
As I mentioned in another comment, if battery technology is super cheap then it benefits all power generation, even coal, because it would marginalize the fluctuating operating costs. Nuclear would actually be perfect because current nuclear reactors are kind of like diesel engines, they thrive when operating at a steady, ongoing power so we could fill up batteries all day and night.
That's an excellent point. Every power source would be boosted by better/cheaper batteries, even coal, nuclear, and hydro. In fact it could actually hurt solar/wind because with lots of batteries you could rely on a much smaller total generating capacity equal to just a little over average power usage (since peak loads could come from batteries). So there'd be less demand for new capacity of any sort to be built. It would also improve the safety of fission power since it would likely be easier to provide extended electricity to the cooling system in case grid power goes down.
It all hinges on batteries. I really really hope we find something. So many innovations have been held back by inadequate or expensive energy solutions. Portable, powerful and efficient energy storage could allow so much.
We do actually have "Portable, powerful and efficient energy storage" - it's called gasoline :) (Or natural gas.)
Think about the insane size of the inverters you would need to power the grid off of a DC battery.
Instead you use cheaper types of energy during the night, and avoid the natural gas. Then during peak usage you fire up your natural gas battery and run a turbine.
Density of power is what matters in the long run. We need a solution that produces the most power for the given space it occupies. Hence, it's not a question of 'if' we use fission, it's a question of 'when'.