All the private fusion companies making very interesting progress. https://www.helionenergy.com/ https://cfs.energy/ https://www.tokamakenergy.co.uk/ https://tae.com/ Insert below; jokes about its being 25 years away, and comments about how it will never work etc
My concerns have moved to "okay, what is the cost of things even if energy is 'free'?". For example, desalination -- currently the majority of the cost of desalination is in the energy used, but even if the energy is free, the materials cost and capital expense is currently about 40% of the cost.
Will the cost of the inputs also go down dramatically as a result of fusion? Or will desalination still be cost prohibitive for most developing areas due to materials? If desalination price falls 99.9% -- what environmental costs will be associated with the extraction/transportation of necessary materials as well as the warm & highly saline effluent that will be dumped into surface waters?
With unlimited clean energy, some ridiculously inefficient schemes can become practical, such as removing CO2 from the atmosphere.