Sure, but energy density (which is essentially hypothetical in the case of fusion, because we don't have fusion power) has got very little to do with the assertion that nuclear energy (and fusion in particular) is the only way to avert a looming energy crisis?

nuclear energy density is derived from e=mc2, so fusion/fission are in the same ballpark.

Current accepted way is to build solar/wind and redesign grid to deal with intermittency. Solar and wind are even more energy diluted than fossil fuel, they take 500 times more space, more land out of nature/alternative uses.

Nuclear has already demonstrated that it can decarbonise industrial economy up to 80%, see France. and they did it just in 10 years.

This is bascally the reason i think this is the way out of crisis

All for nuclear, but the amount of land used is higely exadurated. It is actually totally trivial if you run the numbers.

In reality >90% of worlds valuable land use is farming. Factories, cities, houses, etc. all hardly matter.

Well, one example. I live in Singapore, and for it to become energy independent, it would need a square kilometer for a nuclear plant. To achieve the same with solar, you need to pave the whole country with solar panels.

Besides, to make these solar panels you need to spend energy too. and EROI for advanced solar is about 20, where for nuclear it is 80+.

I think people should stop using nature when they can get the same/better results without using it/using several orders of magnitude less of it.

I view renewables as energy farming, and city-states like Singapoure, lixemburg, etc. Are not very suitable for either form of farming :) for most countries the calculus is very different. UK has been developing sea based wind turbines quite succesfully, thats something that could work for singapore.

I view nuclear as a bit of a lost cause to be honest, they take long time to build, cost a lot upfront, you need a lot of expertise around them, and they would require a miracle of PR. It does not appear likely that countries that do not have an established nuclear industry will suddenly become nuclear powered. Thats just the way things appear to be heading, and its a shame.

Besides, don't underestimate the infrastructure needed to refine fuel, manufacture fuel rods, deal with waste, etc. If you outsource all of that, you are not terribly energy independent.

I think the only hope for nuclear industry is small modular reactors, and that's only if a massive amount investment comes through.

What I meant is ofcourse de-carbonise economy, Singapore can't be energy independent in meaningful sense as it does not have fuel sources of any kind. And solar/wind do not count as there could totally be still nights.

I frankly dont understand how an energy source that can shift from 100% to 5% capacity on its own whim, independent of its user's needs could get so much attention and considered viable replacement for something predictable..

There was not a single economy decarbonized on solar\wind, even for those that tried really, really hard (see Germany). And we have example where it worked, in short 10 years.

There are countries still that can build nuclear on time and on budget - see South korea for example. Wonder why they don't get all the orders for urgent decarbonisation needs.