It's easier to upgrade a gas fired power station to increase efficiency/reduce pollutants than it is to upgrade every vehicle on the road. In practice, I'm not

It's easier to upgrade a gas fired power station to increase efficiency/reduce pollutants than it is to upgrade every vehicle on the road. In practice, I'm not sure that's true at all. For small incremental changes you may be right, but I suspect there's a limit as to how far you can take the existing generating system. The time and bureaucracy involved in building a NEW generating station is immense. I don't have figures handy, but I suspect that from conception to actual production, it takes more than couple of car replacement lifecycles. So in that timespan, the large majority of cars will have aged themselves into replacement anyway.