I was listening to British Broadcasting Corporation (BBC) news recently via WNYC-FM and heard a report that Parliament has passed legislation to the effect that all "petrol" and diesel fueled automobiles are to cease production in the UK by the year 2040. In twenty-three years, all automobiles are to be differently powered.
I read about hydrogen powered cars as one alternative where the combustion products of that fuel are "harmless" water vapor. However, humidity levels here on Long Island in the summer can be very oppressive and stifling. Local weather reports frequently address that issue. Now imagine having hundreds of thousands of hydrogen fueled vehicles adding their water vapor emissions to already way too high humidity levels and suddenly water vapor emissions don't look so harmless anymore.
Furthermore, I recall having once read a rather alarming article that there is approximately a ten percent loss of hydrogen that occurs whenever a vehicle of that design is fueled up and that the escaped hydrogen is a very powerful greenhouse gas. That is not so harmless either.
Alternatively, completely electric cars have historically had issues with limited range. Although there has been admirable range improvement of late, the recharge time of an electric car's battery is still quite long. You can't just pull up into the equivalent of a gasoline filling station, somehow "tank up" and drive off and if you are driving cross country, you need/want to be able to "refuel" and move on right away.
Although battery swapping has been proposed as a possible solution, that swapping would mean having to lift and move around some pretty heavy objects. Batteries are not light in weight and that is an unsolved problem.
It would appear that Parliament has passed legislation which decrees that future technological breakthroughs shall be made in a prescribed time span. Historically, that kind of planning for the future hasn't worked out because breakthroughs just aren't that predictable.
Back in the 1950s, there were predictions of rocket borne postal service, of personal valet robots and of atomic powered airplanes. In the 1980s, Dr. Teller told President Reagan that spacecraft x-ray lasers were an imminent breakthrough for the "Star Wars" defense system.
None of those predicted breakthroughs ever came to fruition.
I hold that with the apparent intention of doing something good for our global environment, Parliament has committed a regrettable folly. Such is the price of not having carefully thought through the consequences of their action.