If you are a careful driver and plan ahead to avoid quick braking, and also accelerate at a very modest rate your benefits would be small with this kind of system. It helps compensate for aggressive driving but it seems like it won't benefit drivers that already are trying to get good gas mileage.
I live in a modest coastal city where the traffic is relatively sedate. My main problem avoiding unnecessary use of the break pedal is that so many traffic lights appear suddenly as you crest a hill or exit a sweeping turn giving you no immediate indication of phase, and then BAM! just before the point of no return it goes yellow.
I pretty much make all my velocity decisions in phase space: how close in position/velocity to I wish to be with the traffic around me at which points in the terrain? I've read that gasoline engines are at the top of their conversion efficiency mound when producing about 2/3rds of maximum rated power, so I'm not shy about briefly laying it on to make a quick adjustment in phase space, but always with the goal of making the least possible use of my brake pedal later on.
Also, we've pretty much capped our top speed at 90 km/l since we're driving a small truck. We had a lovely Toyota Truck from way back that traded some paint at xmas. The smallest replacement truck we could find at a fair price is the ubiquitous Ford Ranger, which is a complete joke as representing a "small" truck.
The chicken tax: Why it's hard to find a small pickup truck
Fifty years ago, the United States slapped a 25 per cent tariff on imported brandy, dextrin, potato starch and small pickups. This was in retaliation to tariffs on imported American chicken imposed by countries like France and Germany.
To this day, the 25 per cent tariff on small pickups remains.
Sad news, ideologues. The entire electable spectrum has left the chicken tax alone, from Nixon to Bush to Clinton to Carter.
Countdown traffic lights may cause accidents, study says
Guess what? The carbon emissions also have a definite consequence. If not climate, then conflict. What's really going on here is escaping the horror of first order terms; it's an actuarial NIMBY effect. One death is a statistic. A billion deaths are somebody else's problem, if the coefficient can be construed as the least bit vague.
The real problem with countdown lights is that they require driver judgement. What you really want are a kind of runway light which indicates whether, from where you are—maintaining your current speed—you're going to make it through or not. The number the driver needs is dependent on individual conditions.
One way to do this would be to pot amber indicators in the pavement calibrated to the speed limit (it really should be called the "speed notice" or the "speed weed"—expect to be noticed/plucked if you drive faster than this). If you're driving at the speed limit, and the nearest such indicator in your forward path is illuminated amber, then you will arrive at the intersection in the amber condition.
If you gun it from 150 meters out from some low initial speed, you'll probably notice that you're losing the race with the amber rabbit in time to rethink your testosterone surge. If not, count on losing the long war of technological measures designed to strip you of your driving privilege. Driving stupidity/dead pedestrians breeds cameras. What part of this simple equation can't these people figure out?
This helps to explain the mysterious Flynn effect, where IQ is purportedly rising in the general population, but it's hard to see in real life. Nobody takes an IQ test sitting behind a steering wheel after rushing out of the house 15 minutes after waking from a dead sleep to a shrieking clock, still fumbling with your phone to check that there's nothing vital you need to know before arriving at the last minute to an important meeting, first thing. That would cancel out the Flynn effect faster than McD's can serve up an egg McMuffin.
IQ is like the mass of the electron uncorrected by the Feynman diagram. Most people spend much of their day swathed in moron/anti-moron particle pairs with a half-life of about 200 ms. Plenty of time to bend metal.
Flywheels do a good job of capturing moronium heat loss from these interacting causes: poor public design, and brain-dead driving public. However, with less moronium in the first place, we could have better design and better decisions. A flywheel weighs about as much as one passenger and you carry it all the time. Cluons are like neutrinos. The extra mass is almost imperceptible.
Guess which is coming down the pike.