We all know fuel efficiency is a worthwhile goal, but changing things on a vehicle takes time and a lot of engineering, and it is costly, partly because of all the testing that must be done. And then, even after one vehicle has some gains, that leaves all of the others, unchanged. So the net improvement is small and arrives slowly.
So perhaps it would be worthwhile to consider a different approach to reducing fuel consumption, which would be to reduce inefficiency in areas where we already know what the answer is and how to do it.
One way is to reduce the fuel wasted by cars and trucks is to keep them moving. The math is so simple that even a senator can figure it out. A vehicle stopped at a traffic control is getting ZERO miles per gallon. That means that it is wasting 100 percent of the fuel consumed. This is true even at stop signs, where the stop may be for a very short time. The new crop of high-efficiency vehicles saves fuel by stopping the engine. The current fleet is not designed for that type of service.
Next, consider that a vehicle accelerating up to speed requires several times as much energy as it takes to keep it at speed. Dragsters are the ultimate example of this, burning a gallon or more of fuel (gas) in a quarter mile.
So now we know two least-efficient functional modes. So how can we reduce the time spent in these inefficient modes?
Here is where I offer, for free, my plan to improve the fuel economy of most of the vehicles in the U.S. It consists of two sets of actions neither requires any new developments or "wonderful new science."
The first thing is to eliminate four-way-stop intersections. Remove two stop signs and change the others to "yield" signs. And on intersections with only two stop signs, exchange them for yield signs. I know that some will claim that all four sides must stop for "safety," but they fail to acknowledge that too many drivers assume that the other one must stop, so they don't. And if there are multiple vehicles stopped, who goes first may not always follow the prescribed rules.
A second answer is to have traffic lights timed so that traffic can flow along the roadway, rather than being halted at every signal light. In some areas it would be better to remove the light and use yield signs. In locations where that would not be safe, a demand light that would only cycle when a vehicle arrived at the red light would be a better solution.
So there are two simple and relatively inexpensive ways to reduce fuel waste for all vehicles. No new engineering required, but likely a huge amount of political resistance to be overcome.