We have numerous designs that claim to be better and safer.
They haven't been built. You can blame "NIMBY", but the nuclear industry hasn't exactly done what it can to fix its current reputation for continually costing multiples of initial estimates, taking multiple times longer to build, and failing multiple safety and other regulatory requirements.
We have a really good, efficient, nuclear fusion supply, guaranteed to work for at least the forseeable billions of years, safely located 8 light-minutes away from the ecosystem that we're trying to protect.
We also have a thermal side effect from that fusion supply, combined with the rotational energy of our planet, that provides atmospheric fluid energy transfer capabilities that can also be used to generate power.
That sounds great, yet the realities of solar are very different from the dream of solar.
I say this as someone who purchased and installed his own 20 kW array on a custom- built structure (not on the roof). To put it in simple terms, the system will likely never be profitable. The overall cost and ten to fifteen year lifetime of the components is such that I can’t see or predict when it will break even. My assumption is that all the panels will need replacement in 15 to 20 years, possibly less for the electronics.
Note that this does not include a battery system. This, given the short and long terms economics of the system would be a ridiculous purchase today.
And this is at a reasonably favorable latitude. Start going north and solar becomes far less attractive.
I genuinely wish we had not gone solar. This was likely the single dumbest and worst investment of my life. Anyone thinking otherwise likely doesn’t have solar or never truly analyzed the real economics of their systems.
I also have lots of neighbors with solar, most of which were installed by companies. In nearly every case they are worse off than they were before. The only ones who are not are those who did not pay for their systems directly.
Theory vs. reality are very different things. I am not even going to analyze the cost of such installations when government agencies are the builders. I’ll just guess the number us somewhere between 5x and 10x “civilian” costs. I say this as someone with experience selling technology to government agencies. Simple example: The California high speed train. We were told it would cost ten billion. We are at a hundred billion and I don’t think we have completed ten miles of slow speed train yet.