Vehicle to grid isn't required for what I'm describing; as a first step you can just allow the grid to decide when to charge the cars, which will account for ~2

Vehicle to grid isn't required for what I'm describing; as a first step you can just allow the grid to decide when to charge the cars, which will account for ~20% of total electricity consumption. Tesla claims their latest battery packs will be good for 1 million miles; if true, they'll be more than good enough for vehicle to grid use. Even with today's endurance levels though, there will always be some amount of vehicle to grid transfers use that would make sense, since you can use it to shave off expensive peaks in demand. I don't know about Ireland, but in Australia that gets extremely costly: https://www.afr.com/news/policy/climate/wholesale-power-prices-hit-record-in-march-quarter-20190407-p51bnf https://www.afr.com/news/policy/climate/wholesale-power-pric...