Earlier quoted context omitted.
Not all batteries need to be mobile. A 1 GWh grid scale battery takes up about 4 hectares at the moment. The UKs total energy use is about 2,000GWh a day. It would need to use 240,000 hectares to store all energy requirements (eletric, transport, heating etc) for a whole month. Even in extreme cold conditions it would last a couple of weeks. That would be about 1% of land use.
Instead of batteries, why not green hydrogen or green ammonia? Ammonia is needed for fertilizer, storage/logistics are a solved problem. Emergency plants around that can use ammonia as fuel can solve the dunkelflaute problem? Another option is natural gas peaker plant on a ship/barge. Have a fleet of these around that can dock at any port and supply electrictity. A peaker powership is essentially a mobile, marine-cla…
Once you 2x-10x the cost of electrolyzer capital by only using it rarely, more generation and throwing away the excess electricity often makes the most sense.
Nuclear ships are similarly super super expensive. The only reason we build them at all are for their unique and wonderful operational capabilities, as in not needing to surface or refuel. Using nuclear ships for power would so expensive that we may need to up our GDPs 10x before such wasteful use makes sense. (Though I'm hoping we do reach such future luxurious lifestyles!)