If drag from air-resistance and other friction were not an issue, high speed would not require great power. Presumably trains are relatively energy-efficient because of their low rolling resistance, long length, and lack of starting and stopping. But for driving, more power is required for acceleration, more rolling friction for stopping and maneuvering, and high speeds make wind resistance the biggest power-drain. Low speed limits (55) were once imposed on highway traffic but this was extremely unpopular. Could the problem be that as long as cars are designed for quick acceleration to higher speeds, there will be little progress in energy-conservation. If, however, horsepower limits were imposed that limited vehicles' power, this would necessitate lower speeds as well. Model T Fords had 20hp, a curb weight under 2000lbs, and a top speed of @45mph. Could energy-conservation be as simple as slowing down?

Well we're also impatient, we don't want to move slower we want to move faster. Slowing down does improve mileage most definitely but it needs to be accepted across the board, If your late are you gonna travel slower? Energy conservation is all about getting the most out of fuel used, If everyone capable resolved to use public transportation as often as possible that would be a great stride. If we super insulated homes and turned off electrical appliances when not in use etc etc. But the vast majority do not quite understand how serious the issue is.

 

Most of us are guilty of not feeling minor inconveniences are worth the bit of energy it saves so we don't.