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Hybrid Cars No Better than 'Intelligent' Cars
eldavojohn writes "There's no doubt been a lot of analysis done recently on energy consumption, especially on the road. Now, a study released today reveals that cars with traffic flow sensors built into them can perform just as efficiently as hybrids. The concept of an 'intelligent' car that communicates with the highway or other cars is an old idea, but the idea of them using sensors to anticipate braking could vastly reduce fossil fuel consumption. From the article, 'Under the US and European cycles, hybrid-matching fuel economy was reached with a look-ahead predictability of less than 60 seconds. If the predictability was boosted to 180 seconds, the newly-intelligent car was 33 percent more fuel-efficient than when it was unconverted.' Now, the real question will be whether or not you can convince consumers that the three minutes of coasting up to a red light or halted traffic is worth the 33 percent less gas and replacing your brake pads/cylinders less often."
From the tone of the post, it seems like they're making an argument against hybrid cars by showing that they're no more efficient than regular cars with this new tech... but why not just stop comparing the two and combine them? Shouldn't the title read "Hybrid Car Efficiency Improves Even More with new Technology?"
Yup, they lose the debate through the old "Not mutually exclusive" argument. Not only that, but those "intelligent" driving techniques aren't always practicable, like in bumper to bumper traffic. That sort of thing is where Hybrids really shine - where speeds are averaging less than 20 mph and people spend time sitting. If I'm in a hybrid, my engine cuts off and I run off the battery for the start-n-stop traffic, and it charges back later. A regular car will typically get well under 10 mph in such situations; a hybrid will get around 60.
In other words, hybrids totally kick ass in the city - small, nimble, typically a short turning radius, and great mileage in city driving.
I have a honda insight, and since I've moved to Providence, RI, I've seen my fuel efficiency drop from an average of 70 miles per gallon per tank of gas (in Connecticut driving mostly on back roads at moderate speeds) to 60ish (mostly city driving) in Ann Arbor, to barely 45 mpg here in Rhode Island. I am convinced that it is mostly the fault of poor traffic planning here. I've never seen a city with worse timing for the lights. You will often get a green light only to be forced to stop 30-40 feet away at another light that turned red the very instant your light turned green (Benefit and Waterman/Angell anyone?)
with that said, i always did wonder how much of my great mileage in Connecticut was due to the fact that I could watch and keep track of my mpg. ie. would I see a similar increase in mileage in a non-hybrid car just by being able to monitor my driving efficiency?
That's not a new technology; I had a Ford T-Bird back in the 80's (when it was the big boat) that flashed a red "Economy" light on the dash when you floored it. And you are correct - unless I was trying to pass a truck on a two-lane highway, when the light flashed, I would usually lift my foot off the gas.
What was once true, is no longer so
Try a ScanGauge. I don't have one, because my car's too old, but a Yaris (actually, most 1996 and newer cars) will almost certainly work with it.
In practice, the engine runs at a variety of speeds, but it seems to prefer running the engine at the most efficient speed and torque when it can.
This post is encrypted twice with ROT-13. Documenting or attempting to crack this encryption is illegal.
Sorry, but there is more to it than "keep the engine RPM low". There is a "too low" point also.
I drive a Chrysler Sebring, and as one of the OPs talked about on his relative's car, it has a digital display of "at that second" MPG as well as an averaged MPG (and a bunch of other things). And between that and watching my gasoline receipts, I know for a fact that my car gets its best mileage at approximately 2000 RPM. It sucks gas like a big dog above 3000 RPM...but it also starts getting bad as it goes below 1500 RPM, and gets worse the further down it goes.
I want a new quote. One that won't spill. One that don't cost too much. Or come in a pill.
Coasting in neutral to a stop may actually consume more gas than coasting in gear. Modern fuel injected cars cut off the fuel supply to the engine when the throttle is closed, and the engine above idle speed. That means if you coast to a stop in gear (compression braking), you're not using any fuel. If you shift to neutral while coasting, the engine speed will drop and it will start using fuel to maintain idle.