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Cars are like horses: people will soon realise EVs are just better, claims VW boss
(www.autoexpress.co.uk)
This is a most excellent place for technology news and articles.
Combustion engine efficiency is limited by hard physics and modern day combustion engines have gotten impressively close to that theoretical limit. So no, the remaining potential of ICE is not that great anymore.
Actual efficiency of BEVs is way better than even the theoretical limit of ICE.