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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."
I thought just "not excessively racing the engine" saves gas, i.e. using cruise control, coasting, etc. Can't we just teach people to do this now? If you have to push on the gas to pass someone, does the chip say "nope, too much gas"?
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In my opinion, the chief function of hybrids has always been as a stepping stone. They're not great in and of themselves, and anything that merely reduces gasoline consumption rather than replacing it can be seen as something that prolongs oil dependence and all the problems associated with it. However, adoption of hybrids shows the big guys that the public is willing to invest in new and more efficient kinds of vehicles, and will hopefully fuel research into alternate energy sources.
u-bend
A feeling of having made the same mistake before: Deja Foobar
I drive a Ford Focus 2007 sedan and in the first couple weeks I had the car I drove fairly sporty [e.g. speed limit all the time no coasting] and got about 13L/100Km in the city. I've spent the last week and a bit driving more carefully, that is, coasting to stops, using cruise control whenever possible, not accelerating as quickly to the next redlight. When I filled up yesterday I purchased 15L of fuel for 154Km of distance. or about 10L/100Km.
In yankee, I'm getting 23.6MPG now instead of 18.2MPG (both in city) for a boost of 29.7% more MPG. I still do the speed limit, I'm just not as heavy on the gas. And when I hit the speed limit I use cruise control where possible. I also don't keep constant speed when there is a red up ahead. Usually I'm doing 20-30 kph under the limit by time I have to brake. If this could be helped via a computer I'm all for it.
Obviously my "study" isn't really comprehensive. But given that i do the same 14Km route every day there aren't a lot of variables in the mix.
Tom
Someday, I'll have a real sig.
I drive a lot for business, about 1500 miles / month in L.A and other parts of southern California. I have a conventional IC car, and driving carefully can save a significant amount of money, so I've tried to drive like TFA says...but this whole scheme does not take into account the guy behind you - the one who wants to rush up to that red light. They will honk, swerve in and out of traffic to get around you, and generally cause more trouble for you and surrounding drivers than it is worth.
The nature of hybrids means they are already recouping a lot of the wasted energy from slowing a car. That would make me expect that hybrids would receive less of an energy conservation boost from intelligent controls, but that they would be able to break later and still retain the same performance that conventional engines with intelligence have. So the net energy consumed would be (roughly) the same over all, but Hybrids could drive faster.
-Rick
"Most people in the U.S. wouldn't know they live in a tyrannical state if it walked up and grabbed their junk." - MyFirs
OK. This is great and all, and SHOULD be pursued.
However
Hybrids are deployable on an individual basis. I can but a Hybrid today, mix in with the existing traffic and infrastructure, and immediately get some benefit.
These "Intelligent" cars seem to assume a huge infrastructure update. They also/alternatively seem to require that everyone else upgrade their cars for me to see the benefit.
Like I said, I think that this concept could be a good thing, but from where I stand, it looks more like the "mission to mars" or the "hydrogen economy": a pie in the sky concept designed to kill off any practical partial solutions while everyone waits for nirvana.
Coordinate the damn traffic lights. Yes, maybe I do have a knack for triggering a red light when I drive up to it. But what I don't understand is why on major expressways (essentially freeways through urban areas with traffic lights), red lights are triggered when a single car comes to a stop at a small cross road. The net effect is that in order to get a single car across the road in less than 20 seconds, 10 cars have to come to a stop for 20 seconds.
Seriously, is it that hard to tie the road sensors to timing chips? It doesn't even have to be done on all roads - but anything labeled an expressway, as well as a major roads with known traffic patterns should all have coordinated lights at all times. Expressway cuts through residential areas for 3 miles? Have a green wave run one way in the morning and the other way in the evening. Major road intersects with expressway? All lights on that major road are timed according to the same mechanism, except the one that controls the intersection with the expressway. It's not perfect, but it doesn't have to be. Any improvement over the current idiocy of stopping 10 cars to prevent one car from idling for more than 20 seconds will result in a dramatic improvement in gas mileage.
How do I know? My car computer shows average gas mileage, as well as current. I can improve my gas mileage from 27 mpg to 32 mpg if I manage to coast through major roads at 45 mph, instead of having to stop at every friggin red light. All it takes is to have a timing chip control each light, program it according to traffic patterns and expected (or even desired!) speed of cars, and you're done. Instant improvement in gas mileage, and instant reduction in oil imports.
It boggles my mind how Europe had those things down pat 20 years ago, but here they still don't get the concept of a green wave on major roads.
Those who can, do. Those who can't, sue.
As others have already pointed out, hybrids could benefit from this too.
I have a prius. I have a 20+ mile commute one way. Yesterday I averaged 70.3 MPG for the trip home. I did this using manual "look ahead" and very carefully planning braking and coasting just to see how high I could get it. You can easily blow 10MPG with one bonehead maneuver from lack of attention but this manual concentration on mileage is probably as distracting as talking on a cell phone.
I'd welcome the technology in my prius or in my SUV. Both can benefit.
No, what we need is an utter lack of drivers. Eliminate cars and highways entirely, and spend the money on some alternate system instead. I like the idea of an electric PRT (personal rapid transit) system, although whether anyone will ever step up and build a useful one remains to be seen. In this world of pork and boondoggles, the answer is probably not. And of course the transition is difficult to impossible. But it would certainly be better for all of us.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
You're pretty close. One of the biggest advantages hybrids have is that you can drive them just like a typical ICE car and get better mileage. However, if you start adding in prediction of driving conditions, your mileage will go even higher. I drive a Prius, and when I drive it like everyone else drives, I get around 50-55 MPG. When I predict what's ahead of me and plan for it to save gas, I get around 60-63 MPG. If I drove like a true hypermiler, I could get much better. The regenerative braking only recovers a portion of the energy you've already used. It's better to use less in the first place. But even when "coasting", the Prius is still recovering a small amount of energy. The only real way to get it to coast is to actually put the car in neutral or deadband the engine (there is a point at which the engine stops regenerating, but still isn't providing motive force, depending on conditions it can be REALLY difficult to hit). But either way, the intelligent car won't do any good if the driver can override it, because very few people want to drive conservatively.
There are a few places that do this, mostly in tourist areas. Ocean City, Maryland has a rolling green light timing that works very well. Here in Birmingham, US 280 is a prime example of a road in need of proper timing. With lights, it can take an hour to get 8 miles, without, it takes 8 minutes. If I drive during rush hour all week, I get 280 miles to a tank. If I drive all week when there is no traffic, 400+ miles to a tank. Just because of the traffic the lights cause to get small feeder road users onto the main road.
While I agree with what is safer, you shouldn't take this attitude. You are NOT causing the person behind you to tailgate you. Only they can do that. That's why it's called tailgating and not frontbumpering.
Not all of them, just most of them. Get the mass operating that way, and the prisoner's dilemma will work for us, not against.
Of course, even that would be a monumental achievement...
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
We have "personal rapid transit" and its called "cars."
Are you suggesting is installing train tracks to every house and business in america? And then people need to wait for a vehicle to pick them up? Or will they own their own? (like a car). Also, how will this system deal with passing, and avoiding obstacles, such as children running out on the tracks (which would now be everywhere, in your trasnportation "utopia").
If your main point was that it should be electric instead of fossil-fuel based, then I agree with you... but in regular cars and using our existing road system.
Whats better than a hybrid?
u gin_nation_g.html
o _wheels.html
Building a better hybrid.
In particular a plugin hybrid electric vehicle.
Or in this case a prius with a bigger battery.
(Although a fully electric car, with the bare minimum for a gasoline generator is more ideal)
This study found that in regions where electricity comes primarily from natural gas, a plugin hybrid puts up 3x less CO2 emmisions.
And in the least green region of the United States powered almost entirely by coal.
They found that the CO2 emmisions per mile were practically idential to a normal hybrid.
http://www.aceee.org/pubs/t061.htm
Whats more, we could replace 84% of the US fleet of cars with electric, and not need to build even 1 new power plant by leveraging downtime grid usage. (More fuel use, but no new infrastructure needed)
http://blogs.business2.com/greenwombat/2006/12/pl
Whats more, by having the distributed battery network stabalize the grid capacity.
We could actually make the grid far more reliable than it is today.
http://www.technologyreview.com/Energy/17930/
http://news.com.com/2100-11392_3-6174672.html
And there's some pretty sexy electric cars on the way.
http://www.greyfalcon.net/electriccars.png
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Cool part about all this?
You can get electricity from the grid at a cost similar to 50 cents a gallon.
http://www.greyfalcon.net/plugins
And it's the perfect, "flexible fuel", since electricity can come from practically anything.
Unlike Ethanol for instance, which might be even worse than gasoline in pollution.
http://www.greyfalcon.net/ethanol2
http://www.greyfalcon.net/ethanol3
And biodiesel, which could potentially make Indonesia/Malaysia put up more CO2 than China.
http://www.greyfalcon.net/biofuel
Best part about this from an environmental perspective, is that combines two big problems into one.
So all you have to do is green the grid, to green everything.
And that can readily be provided by printable solar panels
http://www.greyfalcon.net/pv
And geothermal using inexpensive super powered electric drilling motors
http://jcwinnie.biz/wordpress/?p=1206
http://www.rasertech.com/media/movies/html/well_t
http://www.insidegreentech.com/node/1088
Cheap gas is why MPG hasn't gone up. And gas is being kept at an artificially low price by the "defense subsidy": we're using general tax revenue to pay for an enormous defense force, a main function of which is to maintain stability in the middle east. If motorists had to pay a gas tax to fund the portion of the defense budget devoted to USCENTCOM (plus other oil producing areas such as Nigeria, Indonesia, Venezuela, etc... but CENTCOM is by far the biggest), you'd see prices that reflected the actual costs of providing gasoline, and MPGs would go up in a big hurry.