Slashdot Mirror
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."
But what aboout Hybrid Itelligent Cars being beter then Intelligent cars?
the two techs could easily be put together in the same car, and make something much more efficient.
34486853790
Connection too slow for X forwarding? Try "ssh -CX user@host"
What we really need are intelligent drivers. You know, the ones that don't drive 20 over the speed limit, don't tailgate, keep their cars in tune and the tires properly filled.
'Loose' is when your pants are three sizes too big. 'Lose' is when you misuse 'loose'.
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?"
You don't need sophisticated sensors for this; in most situations, your vision alone is enough to give you 60 seconds of forewarning, or close to it, if you choose to drive "intelligently."
... the capability for "intelligence" is there, but people choose not to do it.
However, most people don't. They'll accelerate when they know there's a red light or stopped traffic in front of them, even though it just means they need to brake harder (and probably come to a complete stop, which they might have avoided by slowing down sooner); people follow too closely on highways and have to use their brakes, which really shouldn't be used for anything except emergencies (and the flashing of which screws up traffic behind them, because people think there's a problem); people mash down on the gas when they're just going to have to stop again in another 100 feet
Perhaps when gas costs more, people will choose to drive more efficiently.
"Ladies and gentlemen, my killbot features Lotus Notes and a machine gun. It is the finest available."
Can't we just teach people to turn off the water while they shave or brush their teeth to conserve water? Can't we just teach people to set their thermostats a couple of degrees higher in the summer and lower in the winter to save electricity and gas? Can't we just teach people to take colder showers? Or turn off the lights when they leave a room?
Yes, teaching people better habits is a nice thing to do, but getting them to actually drop their old bad habits is an entirely different story. Our oil problems would be greatly solved if everyone stopped driving their cars and started riding bicycles for any trip less than, say, 5 miles long, but that isn't likely to happen. We must solve these problems through technology because making other people change their lifestyle is just not practical. Most people will resist, and even those who don't are likely to go back to their old ways because people are inherently lazy and will take the path of least resistance whenever possible.
The article says they're not better, but don't claim they're worse either. Why does it matter to you, as a car owner, what makes your car more efficient. The bottomline is what counts, and if intelligent and hyrbids are both efficient, then great.
Also don't forget there are more reasons for hybrids to exist. We're not going to run on oil forever, and the effect it has on preparing the market for a chance shouldn't be downplayed. Plus, we have R & D and manifacturing/safety practices in the development of those cars won't go to waste, when "the time comes".
If anything, the real question isn't "why drive a hybrid when you can drive an intelligent car", but "where the heck are the intelligent hybrids?"...
Yeah, but every once in a while we get through and leave you slugs behind, making it oh so worth it!
Please sign petition to restore sanity to our banking system!!!
http://financialpetition.org/
Since this system has no overall control agent, the cars are like a distributed computing network. Since most traffic is caused by faulty driving I welcome this kind of thing without hesitation.
How do you stop someone from fixing their car to constantly broadcast "DANGER: MOOSE AHEAD" or "EMERGENCY VEHICLE APPROACHING" so they can use it to get through traffic faster?
I think the abuse potential of these technologies need to be carefully studied. If there's a way that any system can be used to create even the most minuscule advantage in traffic, or simply be used to cause mayhem, people will do it in spades.
"Ladies and gentlemen, my killbot features Lotus Notes and a machine gun. It is the finest available."
First, the technologies aren't incompatible, competing technologies.
Second, the negative spin on hybrids is bizarre: that they—a widely available commercial technology—are "no better" than the tests suggest a proof-of-concept, not-yet-commercially-available technology might be if put into practical use is, well, a weird way of looking at things.
I mean, usually, that a presently available technology does just as well, with less specialized infrastructure, than a proof-of-concept isn't, even if they are directly competing, bad news for the existing technology, its bad news for the experimental alternative. "New, unproven technology offers no more than existing, popular technology" would be the usual way of looking at that.
Of course, they aren't competing technologies, there is no reason a hybrid couldn't benefit from being "intelligent" or vice-versa. Now, you might not get the full efficiency gains of each, since there is some overlap in their benefits vs. dumb non-hybrids, but you would expect more efficiency than either alone.
Hybrid cars are better than the typical cars. Now there's a prediction that "intelligent cars" will also be better than typical cars, as much better as are hybrids. So the correct headline is
"'Intelligent Cars' As Good As Hybrid Cars"
Otherwise the headline is about hybrids, which this story is not about. And it implies that hybrids aren't so good, as if not-so-good "intelligent cars" are their benchmark.
Plus, the research is only a single prediction of a complex system yet to be built, let alone tested, so a correct headline would be in the future tense, anyway.
--
make install -not war
Well, except that I can actually buy a wool coat.
There are 0x40000000 types of people: those who understand 32-bit IEEE 754 floating point, and those who don't.
While I assume that pricing of the sensor system is far cheaper, they really should have given us numbers. If it turns out that installing the sensor/computer costs $15,000, then hey, buy the Hybrid.
excitingthingstodo.blogspot.com
The paper in the first link is just that - it's a paper. This is something that is THEORETICAL. Not something that is actual. It's like Hydrogen powered cars - until you can actually buy it, it is a bunch of hot air.
As for the second article, the notion of cars talking to eachother and the roads is great. That's not the world we live in yet though. This requires auto-makers to start adding this to their cars, as well as massive expensive modifications to the road system. Convincing every state, county, municipality, etc in the US to install this stuff would be very hard - especially since not everyone is a techie. Even if Congress were to mandate it, it would still take a long time to see it deployed.
These things are clearly future possibilities. They are not present options. There's a huge difference. It's fact versus fiction at this point. I think the way that this is presented makes it seem like you have a choice between these two, and that they are competing. This is not an either/or kind of thing. You could put the intelligent car technology in any vehicle - hybrid or not.
Sorry for being a troll. Seems like someone should point this out.
I'm all for more intelligence being used by regular people.
We can end our dependence on fossil fuels and solve the obesity problem in the U.S. in one fell stroke: ban automobiles and give everyone a bicycle.
Not to mention that road fatalities would drop to effectively zero.
I'm not saying...I'm just saying.
Insisting on "correct" English is like saying that there is only one, definitive recipe for chili.
"Our oil problems would be greatly solved if everyone stopped driving their cars and started riding bicycles for any trip less than, say, 5 miles long, but that isn't likely to happen."
I think that would solve a whole lot more than just the oil problems..
MABASPLOOM!
Then we simply need to make the path of least resistance also the most efficient. Any system designer will tell you that you need to make the best choice the default one, because people will overwhelmingly choose the default.
I'm in the hole of the broadband donut.
I'd say 3 miles is a bit extreme, but I have done quarter-mile coasts. Anyway, that's what the happy medium's for.
I go 65-70 on So. Cal freeways. Period. I also manage to keep a healthy 3 second window most of the time. I rarely brake. There are days I could make it from home to work without hitting the brake once (well, if it wasn't for red lights, right turns and parking).
They have room to pass me, and I give them all the room they want. I guess what it all boils down to is I'm comfortable with the size of my penis.
More to my own point: if the car's going to drive itself, why not take mass transit?
-- 'The' Lord and Master Bitman On High, Master Of All
That's the thing, it's not new, it's not expensive, it certainly would help, so why isn't a bill passed requiring all new cars to display mpg statistics? My father's early 90s chrysler had this. You could get current usage, trip usage, and overall life of the car usage. All displayed on a nice little digital readout next to the odometer. I think that at least for some percentage of the population it would ease their driving habits. It almost becomes a game to try to milk that last mpg out. I think this was available for my Jeep, but it came with the special upgrade package that includes the special control panel with the nice sun glass holders in it. Of course it was like $400 to I opted out of it. Just like a catalytic converter, a fuel usage display should be mandated. It's cheap and has potential. Of course the car manufactures don't want it because then people would see how bogus their epa ratings really are.
Human beings consume resources up to the limit of what is available unless they have to pay for it. Well we consume huge amounts of energy because it's cheaper than it has been ever before in history. If energy was expensive people would be very careful about how they used it, including buying more energy efficient devices.
Deleted
125cc Motor Scooter: $2500
Year of insurance for 125cc motor scooter: $98
Tank of premium gas for 125cc motor scooter: $3.84
Getting 80mpg: Priceless.
I'm in the hole of the broadband donut.
Believe me, I've tried.
I often find myself in a half-mile back up of cars at a stop sign. I'm in a rural area that's quickly being developed and adequate traffic control devices (IOW, stop lights) haven't been installed everywhere. It's obvious as all hell that a perfectly reasonable way to get to the intersection is to just idle along. A gap will open in front of me then I'll idle through it. Before I get to the car in front of me, it will have again opened a gap and then stopped while I just idle smoothly along.
Sounds reasonable, right? Well, apparently not. I've had drivers behind me go into apoplectic fits, screaming and flipping me off, because I allowed a half-dozen car lengths to open ahead of me. I've had drivers pass me on the shoulder where there is no shoulder (I literally mean a two lane road with big, scary ditches on the sides) because they couldn't stand to see a gap in front of me. I've had drivers pull out of line, swerve in front of me, then watch their mirror as I idled up from behind and slam on the brakes as I approached, attempting to cause an accident that would be my fault. I hate to ascribe motives to people I don't know, but that seems to me to be just an attempt to "get" me for not driving like everybody else.
Hell, I've actually been stopped in a long line at a red light and had this happen. I was taught that you should stop far enough behind the car in front to see their rear tires on the ground. If they stall out, this gives you enough room to go around. Well, given the right combination of hood and bumper heights, this can also leave enough room in front to fit a small car. On three separate occasions over the past couple of years, I've had the car behind me whip out and pull in front of me (never *quite* fitting into the space) because I left too much room in front of me while we were ALL stopped at a light.
Nope, you can't drive steady in the U.S. It's apparently not allowed. You must floor the gas, roar up twenty feet, and slam on the brakes to stop every time someone in line in front of you clears the stop sign.
People are idiots. No wonder researchers tend to look for technological solutions to human problems.
Perhaps they are talking [out of their ass] about cars that don't use the motor to drive the wheels, but instead use it to drive a generator?
There is no absolutely accepted terminology to separate that type of hybrid from the kind of hybrid where the engine is coupled to the transmission and helps to drive the vehicle directly.
It does make good sense however, because a motor or a generator can be over 90% efficient. Even with those losses added together it's comparable to the loss of a traditional drivetrain, and it has the potential to eliminate substantial weight by eliminating drivelines and the like, although this benefit would be most marked in an all wheel drive vehicle, and is probably least in front wheel drive systems.
And as we all know, gasoline engines are most efficient at a given RPM and load, and they operate at some fraction of that efficiency at all other times. Using a generator-charging system is the way to get the absolute most efficiency out of them.
I'd like to see that option explored with very small direct-injection two strokes, which should be a great way to further decrease weight and improve efficiency.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
I wonder if we'll see a pattern of them getting into *more* accidents because they're constantly watching the gauge instead of the road. I have one of these on my car, but fortunately the display toggles various fuel consumption stats along with the time. Usually, I just leave it on the clock because I find MPG distracting.
I do the same thing, but you have to pay attention to the situation behind you. Coasting to a red light means you're blocking the guy behind you, who may either be making a right on red but has to wait for you to get out of his way, or needs to get to the left turn lane to get the protected left before it changes. If there's someone following me and there's no one ahead turning, I just go ahead and waste the gas, for civilization's sake.
Hybrids? Bah! Intelligent cars? Bah! Drive a motorcycle. I have an early 90's model Yamaha that easily gets 70mpg. On some of the newer bikes, you can get 80 or 90. Some may have broken 100. Plus, you still get to race to the next light, stop, idle, and take off again like you do in your car! Now, imagine the mileage of an intelligent hybrid motorcycle.
:P
Alternate solution: don't ever leave the house. Perfect mileage! Let the pizza delivery guy worry about mileage.
-G
Their may be a grammatical error, misspeling, or evn a typo in this post.
You are right in more ways than you know. In the case of driving, you get better gas mileage in maintaining a speed than you do in stop and go traffic (hence hwy mileage is better than city). City planners need to get out and look at their streets and think about what they can do to increase the amount of time someone is driving*, and decrease the amount of time they are waiting at lights or braking unnecessarily.
Where I live there is a stretch of road that the stupid city planners decided should be the major road. In the course of 1.1 miles there are 10 stop lights. In the next 0.7 miles there are an additional 3 and there are another 4 in the mile before that. There is not enough distance between each one to time them so inevitably you're bound to hit 3 or 4 red lights on a good day. I've had days where I hit every one. It gets worse when traffic is bad, because sometimes you'll end up sitting at a light for two cycles or more. Most of the time, no one can even get to half the speed limit before having to brake again. The only other major roads around are the same way, and the other option is to get into residential areas. But if you do that the speed limit is reduced and you have to choose your course wisely or you'll get a stop sign every tenth to two tenths of a mile. In other words, the road planning is such that it keeps you in very slow stop and go traffic, even if there isn't traffic at all.
If they were to change the layout (which I realize that by now would cost a lot of money, and in some cases is not feasible) they could increase speeds while decreasing accidents and moving violations. In addition they would decrease the total driving time, increase fuel economy, decrease total emissions. The changes would also go a long way towards easing every one's drive which reduces the risk of road rage. People are less likely to run red lights or speed up on yellow because they occur less often.
I used to live in Glendale, AZ. At the time, while all the cities around us were putting in cameras to catch red light runners and speeders, Glendale tried to time their lights such that if you went the speed limit, you would get green lights. First of all, they were able to do this because there was enough distance between lights to allow for it. When they did this, and I realized that it worked more often than not, my driving habits changed drastically. No longer was I racing to try to beat the next light, but instead maintained the speed limit. Sure I hit some red lights, especially during heavy traffic, but for the most part, I was hitting more greens, and driving safer. I noticed that I was much calmer when driving and much less willing to run a yellow light. I don't know if they still do it, but I thought it was the greatest idea ever.
Another thing city planners can do is make residential roads not so straight. Yes, a straight line is the shortest distance between two points, but making roads curved means you can have fewer stop signs (less stop and go), and people tend to drive slower on turns than on straight roads, thus you've built in a speed limiter where little kids and old ladies are walking around.
I'm sure there are lots of other ideas that actually work towards making driving easier, faster, more fuel efficient and safe all at the same time. So you are right, make the default the best choice, and suddenly the world becomes a lot better place.
Stop Global Warming!
Just say no to irreversible processes!
The same way you stop people from using lights and sirens so they can get through traffic faster -- you make it a crime and enforce that rule against people that are obviously breaking it. If they are influencing traffic in any significant way you could see that effect and it wouldn't be terribly difficult to record the broadcasts in the area and correlate them with the vehicle weaving through traffic.
Traffic cops only issue speeding tickets. They don't bother making the roads safer, since there's no money in that. Of course, parking on the side of the interstate looking for someone "speeding" (going over the legal limit, but probably not going faster than the rest of the traffic) causes people to slow down (= wasted gas) in front of faster traffic (= accident) just to avoid some dumbass hick cop that thinks he can use his gun just because he has it.
Fuck that. I'd rather see those asshat cops/HP-men run over by rampaging drivers as long as they ignore real road-safety problems and instead focus on revenue-generation (read: speeding tickets instead of real moving violations). Yes, I just said I'd prefer dead cops over corrupt government. Am I a criminal or a patriot?
Are you saying we're smart enough to operate a 3000lbs vehicle at 60mph, but we'd only commit mass suicide operating a 25lbs bike going 10-15 mph?
I think the point is that people aren't smart enough to operate the 3000lb vehicle at any speed. Mix in a whole lot of 25lb vehicles and this will quickly become apparent.
Woo, the ideal world where one tax does everything. Sounds good to me. Except for the pigs. No more police, ever, anywhere. I don't need to get pulled over for speeding when there's not one other person on the road who I could possibly "harm".
I imagine gas prices will sort things out themselves without any government intervention. With growing awareness of the environment and high gas prices, people will demand energy efficient vehicles. What I don't understand is how MPG has not gone up in the last 15 years. My car is from the early 90s and it gets the same, if not better, mileage than newer cars of its class. How has engine technology stagnated for over a decade?
Buckle your ROFL belt, we're in for some LOLs.
And that spedometer, what waste. Just drive so the trees don't go buy too fast. The tacometer? when the engine whines, shift! Isn't this slashdot where we deserve access to all information? Including our current mpg rate?
In any case, most cars don't. I've yet to buy a car that does have it standard and while they aren't BMWs they aren't bottom line. I don't believe the Honda Accord has it standard, at least 2-3 years ago it didnt.
And guess what, for every M3 and A4 that is bought 100 average joe's do buy bottom of the line cars. These are the vast majority of cars and are where the effort should be directed.
If you want to talk ridiculous regulation take a look at the current bill being proposed which sets mpg limits for the year 2019 or something stupid like that. This is actually a case where the government can actually do something immediately useful and benign at the same time. That's pretty rare.
You are right to point out that gas prices will sort the problem out. It is also worth pointing out that gas prices are the only thing that will sort the problem out.
The timing is off on purpose. There's even an industry term for it: "Traffic Calming."
Traffic calming is how cities get neighborhood associations to stop fighting construction that could cause increased traffic. For example, the city may want to repave or expand the capacity of a critical roadway to improve overall traffic. However, the residents don't want more cars speeding through their neighborhood. So the city agrees to implement "traffic calming" measures to make the route unappealing (read: slow) to through traffic.
It's basically yet another instance of NIMBY.
This regenerative braking technology is why hybrids get better gas mileage in stop-and-go city driving than on the highway.
Half true, or perhaps one third. Hybrids also get better gas mileage because when stopped in stop-and-go city driving they use no fuel. That's a huge gain. Also, energy capture during regenerative braking is imperfect both because it is easy to exceed the maximum charging rate of the batteries, and also because the charge/discharge cycle is not all that efficient (about 70% both ways, if memory serves.)
In any case, things that exist are better than things that do not. Hybrids actually exist. I can't tell from the article if the intelligent technology being talked about is anything other than a simulation. But I am sure I can't go down to my local car dealer and buy a car so equipped, whereas I can certainly buy a hybrid.
Finally, the only reason the story sets up a false and misleading opposition between hybrids and intelligent driving choices (whether human or automated) is that lies of this kind get more eyeballs on the page and sell more advertising, and who wouldn't want to get their knowledge about the future of technology from such a pristine and unsullied source?
Blasphemy is a human right. Blasphemophobia kills.
Roundabouts are far more efficient at traffic control than stop lights. Rather than stopping traffic entirely for one or two cars, traffic keeps moving. When you have a smaller road intersecting with a larger, a roundabout naturally causes the heavier traffic to move more easily through while not preventing people on the less travelled roads from moving at all. It also reduces traffic speeds by presenting approaching cars with a green wall and a sharp turn, forcing them to slow down at the intersection like they're supposed to. They also make it safer for pedestrians by giving them an island of safety in the busy intersection as well as forcing them to look in only one direction to make sure traffic is clear. Finally, you don't have cars crossing each other's paths of travel, so "left hook" accidents are eliminated.
My biggest suggestion, other than more control over zoning to eliminate massive subdivisions that create traffic problems, would be to replace traffic light intersections with roundabouts wherever possible.
I'm in the hole of the broadband donut.
I'm pretty sure it's not... unless you are staring at the cig. Who needs to look at their cigarette? On the otherhand you do need to look at the road.
1. Oh, like the speed limit is anything other than a suggestion.
2. I'd still rather have a reckless driver crash behind me than in front of me.
3. Then let him pass, and back off enough to let him get way ahead of you.
If someone needs to get to the left turn pocket or intends to make a right turn on red, then their turn signal should be on. If it isn't, then any delay caused by me coasting to the light is their own fault.
I think he was being a bit too vague. The fatal heart attack rate would soar. Most people in America don't seem to be able to go up more than three flights of stairs with out taking a rest.
No, I'm suggesting we run train tracks near to every house and business in America. Everyone else can use a golf cart or similar to get themselves and their cargo to/from the PRT.
The system will be smart enough to schedule vehicles to detour them around other vehicles. Busy areas will have sidings, just like we've been doing for trains for decades.
The tracks are elevated in most areas, to get them out of the way. The streets can be reclaimed for bicycles, pedestrians, and local utility traffic. The vehicles can trivially detect obstacles through a combination of RADAR and LIDAR, especially given the uniform quality of their chosen path.
Look, I enjoy the personal freedom of driving a car, too. I love driving! There are few things I enjoy more, and nothing makes me feel more alive, than screaming through a canyon at the limits of the tires, pushing around corners, the works. But I accept the fact that my ability to do this (or even just to drive like a sane person - which is what I do when I'm around other drivers, including slowing down when I spot them even if they're not in my lane because if one of us does something stupid or has an equipment failure we can end up attempting to occupy the same space) is not beneficial to society as a whole, or to the environment, or to a lot of other things.
But the highway system is not the answer. California, which has tons of people spread out everywhere, and tons of square mileage to cover, meaning tons of roads, can't afford the current maintenance costs - and they aren't enough to maintain the roads! As the population grows this is only going to become more of a problem. Sure, California has earthquakes, and they definitely take their tool on roads simply by causing settling. But the rest of the country has various natural events which also destroy roads, so it's not like we have a monopoly on that problem. We hardly do any road scraping or salting, for example.
The nation's rail network was dismantled due to lobbying by the auto industry that wanted that money spent on highways. Well, they got it. Now you can only take trains along a select few corridors. The cost in pollution and simple overall energy expenditure for cars to move all these people as opposed to trains is immense! With trains you have a limited number of vehicles that are used by everyone, running on a highly durable surface. With cars you have a huge number of vehicles, more likely to crash (since they have free movement, at least on one plane) and harder to control from an emissions standpoint, driving on road surfaces which not only take up far more space than rail, but are also dramatically more expensive to maintain because of their very nature.
The PRT concept is a way of protecting most of the things that people like most about cars, while maintaining the benefits of trains. Its only flaw - and it is definitely a big one - is convincing people to buy into it. That alone is probably going to remain a show-stopper longer than I will be alive. But it makes far more sense than the current situation of masses of cars on expensive surfaces.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
It's not that complicated. As the gap between two cars gets smaller so the risk of the following car running into the back of the leading car increases. If I am driving the car behind, I get to choose how big to make that gap, so I can control the risk of collision. If I make the gap big enough, say 2 or 3 seconds, then I can all but eliminate the risk.
If I am in front then I have no control over the size of the gap. If I have to brake unexpectedly I'm trusting to luck that the nut job behind won't run into me.
Since most collisions on the roads are caused by drivers not leaving a big enough gap, taking control of the size of that gap seems like a pretty smart move to me.
We see these stories all the time.
"Hybrid cars are no better than intelligent cars".
Excellent work with the automation system. Now let's put this intelligent autopilot in a hybrid car and see what we can get.
"Hybrids are no better than a modern turbodiesel"
Excellent work with the diesel engine development. Now let's build a turbodiesel hybrid. With intelligent autopilot.
The technologies aren't mutually exclusive. They don't have to be compared against each other. They can be combined for even better results.
Of course, the law of diminishing returns applies. An intelligent turbodiesel hybrid may only be a couple of percent more efficient than an intelligent spark ignition hybrid. But as a research tool and technology demonstration, why don't we hear of anybody building such a thing?
The downside to braking hard is more what your not doing instead. If I don't brake hard I'm letting the car slow itself purely with 'engine braking', which in a modern (ie EFI/computerised fuel system - this might not be the case with Automatics, but it sure is with Manual 'stick' gearboxes) car uses 0 fuel instead of trying to hold the car at a steady speed until I slam the brakes on which uses >0 fuel. Also coasting (as in no acceleration or braking just letting the car slow naturally) up to a bunch of stopped traffic or a red light gives a much bigger window of time where the traffic can move or the light go green so I don't have to stop, I just slow down a bit and any speed I keep is a bit of speed I don't have to waste fuel getting back.