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Improving Mileage: "Hypermiling"
Posted by Heading Out on June 5, 2008 - 10:30am
“So, how many miles does it get?” It was a Sunday morning, and we were looking at my car, and so I mentioned that I had started to change the way I drove. As a result (driven by a little monitor display) I was now getting about 10 – 20% better mileage than the estimate I was given when I bought the car. “Yup,” said the pickup driver I was talking with, “I’ve started doing the same sort of thing. Slow down a bit, don’t accelerate as hard, the little things. And you know what?” He went on, “ a lot of other folk have started driving that way too. Of course you’ve still got the hot rods, but in general . . . .” Of course it helps that we live in a relatively small town, in more of a rural setting.
And just as some three years ago, we had to start learning the new phrase “demand destruction", it may now be time to learn about the new term “Hypermiling.” Because, in terms of improving mileage performance neither they nor I in the league of those that can get more than 70 mpg out of a Prius, a feat highlighted on the CBS Morning Show the other week. The story of how the shoot took place, in itself an introduction to hypermiling, and the adventure of the drive itself is detailed at CleanMPG forums , with the highlights including
Across Indiana, the Prius was holding its own in the 70.3–70.7mpg range while I was traveling in the standard 48–53mph range using SHM of IG14 and TPS of 18 whenever I could. As soon as I crossed the Ohio border (time: 10:47 CST), an off the rear quarter wind began to increase and so did my speeds. 30 miles past the border, the Prius picked up to 71.7mpg. Another 60 miles and she was up to 73.1mpg. I had two quick bathroom breaks inside Ohio but only lost maybe 9 minutes total while the Prius stayed booted up through the stops.
Inside Ohio and 389 miles out, Benno had to refuel while I was only two pips down. Benno in the Standard had traveled 389 miles on 9.37 gallons for a calculated 41.5mpg and 45.3mpg per the FCD. He was playing with the screen and reset his FCD about 100 miles prior but I calc’ed the actual from start to reset and reset to fill. I also passed him while he was refueling but it was not long before he flew by for the second time!
As I say this level of change is not yet widespread, but perhaps one of the impacts of the higher price has been a more conservative driving style from those who have not, in the past, given it much thought.
Yet, as Leanan caught in a Drumbeat piece last Sunday there is no appetite, as yet, to make practices, such as lower speed limits, mandatory yet.
For all the griping about spiking gas prices, there’s no clamor for the return of the little-lamented 55 mph speed limit of the ’70s and ’80s — though most agree it reduces consumption and saves money.
“It’s not that people haven’t thought of it — just no one is even close to discussing implementing it,” said Therese Langer, speaking for the American Council for an Energy Efficient Economy. “It’s not high on anyone’s list.”
Cars, in general, get better mileage than they did back in the 1970’s when the limits were in place, particularly when the limits are below 60 mph.
However it is not a lost cause. Historically speeds on the German autobahn have not been restricted, but this April Bremen were the first to introduce a limit - albeit at 120 kph (75 mph), though there is a difference between the parties on what should be done.
German Chancellor Angela Merkel, leader of the pro-business conservative Christian Democrats (CDU), has ruled out introducing a national speed limit as proposed by her SPD coalition partners.
The SPD voted at a party conference last year to introduce a speed limit of 130 kph (80 mph) on motorways to help reduce CO2 emissions.
Interestingly Wikipedia notes that only three places have no general speed limit, Nepal, the Isle of Man, and the Indian state of Uttar Pradesh.
We are heading out for family related vacation and associated social events for the next three weeks, and may post from the road, if facilities will allow, but it will also give me a change to see how my mileage changes as we do drive more extensively – with most of the driving likely to occur along the East Coast.
Most of the suggestions for improving mileage performance are relatively straightforward , and though there are a more advanced techniques out there, I am not (at least yet) that much of a fanatic that I am likely to be following them all. On the other hand I am going to print the list out, and see how some of them at least work out as we make our trip. And who knows, as the numbers start to creep up on that little monitor every time I shut the engine off, I may become more under its control. We’ll just have to see.
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(source)
The ubiquitous tradeoff between time and energy....
At higher speeds:
(Source)
Interesting that everyone bows at the alter of the Prius, but both the VW and the Opel get better milage on this chart. All of the other tests that I have seen also place the VW TDI above the Prius in milage above 40 MPH.
I think if I could afford a new car I'd go for the VW TDI as it costs less, is much simpler to maintain (and probably cheaper?) and seems better suited to highway operation. Note: I live on a farm in a very rural area and spend 90+% of my driving at highway speeds.
As long as the current differential between petrol and diesel exists which is about 20%, the higher cost of diesel negates the increased mileage of the TDI. As a former mechanic, I would suggest you call the nearest VW service manager and ask what the cost of changing the timing belt on the OHC VW Beetle diesel which does need replacement every 100K or so. It is close to $1000. I do hope that we can get away from these attempts to prolong a POV transportation lifestyle and talk about a transport modality with a future and that will be electrified rail. We probably have 3 or 4 more years of relatively cheap oil until the supply demand curve really crashes and we need to start crushing our beloved Hummers and Excursions now to recycle the steel and start laying track ASAP!
http://www.atsltd.co.uk/
Jon
The Prius is realy optimised for city driving, It does have an Atkinson cycle engine which improves its cruising economy, The VW has the advantage of a more efficient diesel (due to the higher comp ratio) and the higher energy content of diesel. But for your application the VW is a better bet.
HTH
Neven
The advantage of the Prius is in city driving, where it's battery pack actually allows it to get higher mileage in the city than on the highway. That's the opposite from a standard ICE auto.
This graph is somewhat artificial in that people don't drive a constant speed from place to place.
That graph doesn't reflect my Prius experience at all. In good conditions, I usually get 55 to 60 mpg at 55 to 60 mph. (Though I live in Colorado, where the air is thinner and dryer than in most places, and really does make a difference at higher speeds.) In three-plus years I've had only a handful of highway trips under 50 mpg, and all of those involved either cold - low 20s or below - or freezing wind. In the Prius, cold wind and short trips (in minutes) are the real mpg killers.
Mmmmm, interesting.
As 95%+ of my driving is Motorway (on the right hand side of centre :o) I think I'll stick to the BMW Z3...
[E=1/2mvv but mostly goes to 1/2pvvCdA from http://en.wikipedia.org/wiki/Drag_equation]
These guys have got a nice shape: www.aptera.com
Nick.
re: fuel economy vs speed curves
I have a BMW 540 and a 2nd generation Prius and I've driven a VW Beetle TDI across the US. The curves shown are inconsistent with my experience with these cars. The VW got about 48 mpg consistently, as long as I stayed below 75 mph. The BMW will get up to about 26-28 at 65 mph, but doesn't drop below 20, even when driven quite hard on the highway. The Prius needs to be driven at 80 mph or above to get less than 40 mpg, but at 65 it easily stays in the mid to high 40's.
Mark Folsom
Last summer I went to spend a week at my Mom's doing handyman stuff around her house. Denver to Omaha at 75 mph all the way running the A/C, several days puttering around the Omaha suburbs, then back to Denver again at 75 with A/C. 2004 Honda Civic with automatic transmission averaged 41 mpg for the entire trip. All the gas sold in Nebraska has mandated ethanol content, so at least half of that trip was done on E10. I was quite pleasantly surprised at the mileage.
I don't have any driving experience in any of these cars, but the fuel economy at 60-80 mph looks a little pessimistic (a Prius gets 37 mpg at 60mph and 30 mpg at 80 mph?). On my last road trip I averaged 37 mpg in a fully loaded Corolla rental car. I cruised 75-85 mph on the open roads, 60-70 mph in heavier traffic and even sat through an hour of a stop and go traffic jam. I'm pretty sure the winter gasoline was oxygenated with 10% ethanol too.
I took three test drives in the 2nd generation Prius when it first came out. I liked it but it was more expensive than a comparable sized ICE in spite of the government subsidies that were being offered. I was also concerned with the possibility of expensive repairs as it aged. I doubt that the world is going to be saved by hybrids. Still I am enthusiastic about efficient driving and a 55 mph speed limit. I am old enough to recall the 35 mph speed limit of WWII and my father's B card.
Around the time of an earlier gas crisis there was an interesting problem related to the reduction and ultimate elimination of lead in gasoline. The regulations came on fast and and the auto companies found it difficult to adjust. Did tetra ethyl lead save oil? Might be an interesting topic for one of our smart engineers to research. I had a big Ford station wagon at about this time. I did well to get 10mpg.
I can explain that. Tetra ethyl lead is a cheap octane booster and lets engines run higher compression. Higher compression is a win-win all around because it gives better power AND better efficiency. When we moved to unleaded gas in the early 70's because of catalytic converters and environmental effects, unleaded had a much lower octane rating, and automakers reduced compression ratios. In the time since then, we've gotten better at designing combustion chambers that can run high compression on 87-91 octane fuel.
Only 6 years ago, I was driving a 1986 Oldsmobile Cutlass Supreme Broughm that got...
12 miles per gallon.
You could seat 6 comfortably, fit an elephant in the trunk, and almost peal rubber while driving 60mph with the rear wheel drive.
A prius would squash into the grill like a large june bug.
I think the transition to Prius-like cars is going to be a sudden thing in a few years. There are multiple concurrent effects that could make it non-linear.
1)gas prices
2)carbon scare
3)techological proress
4)Nuclear plants plus plug-in options
5)Less fear of the disapearing deadly old steal beasts
6)everyone else has one
We'll wake up one morning and all of the neighbors will be getting 40mpg.
You might be interested in an article that appeared in March in the Times newspaper where a comparison of a Prius vs a BMW 520d driven from London to Geneva using motorways and town driving, a 545 mile journey.
http://driving.timesonline.co.uk/tol/life_and_style/driving/used_car_rev...
According to the test the BMW was marginally ahead despite being a larger car so, your mileage may vary:-)
This website provides both miles per gallon (Imperial) figures, litres/100km and CO2 emissions for new cars sold in the UK.
http://www.vcacarfueldata.org.uk/search/fuelConSearchResults.asp
Nate: I didn't know the Prius was that impressive-my guess is an urban driver in this city (Toronto) would average 70 mpg.
Not likely. Wringing those kind of MPG numbers isn't exactly easy. I have a Prius, and in mixed driving, I'm getting ~53 mpg. In the city, to get that kind of mileage, you have to be very ginger with the gas pedal. Not just a slow accel away from a light or stop sign, but a creep.
All the other drivers on the road will gesture that you're 'number one'.
With their middle finger.
Damac: Thanks for the info.
Brian. Although it is probably possible to get that kind of mileage it would next to impossible to do real world situations without infuriating everybody else on the road. I have averaged 56.2 mpg over the life of my 2006 Prius in mostly suburban driving of 30-45 mph in a warm, flat area of the US. I do try to strive for the best fuel economy I can and will sometimes play with the hypermiling tricks if nobody is around but when in traffic (most of the time) I just go the speed limit. Summer is better than winter. My current mileage on this tank is displayed at 67.3 mpg (usually ~2% optimistic) at about 250 miles on the tank.
As to the the 37 mpg at 60mph and 30 mpg at 80 mph. It is pure rubbish. I'm not sure I could ever get the Prius to 30 mpg no matter how I drove it. I've had mine on a couple of trips from Phoenix to the San Juan mountains in southwestern Colorado. Vacationing, I take the more scenic and relaxed secondary roads and will keep it at about 60 mph. On both trips of over 1000 miles including going over several 10,000' mountain passes on each trip I've averaged over 50 mpg on both times.
Thanks also.
If you're into modifying your vehicle to increase mileage, there are many options for that as well.
For under the hood improvements, some items that increase your HP also increase your gas mileage, assuming you don't take advantage of the extra HP with a lead foot. These examples include:
Underdrive pulleys- These are lighter weight and larger pulleys that you place on your power steering pump and alternator in order to decrease drag on the engine. This means more power to the wheels, which means either more pep to go, or better fuel efficiency. Cost: $70-140 (I recommend AEM brand) (Alternately, if you have a small car and strong arms, you can simply take the belt off of the power steering pump completely. I've done this before.)
Air Intake Sytems- Your engine is like a pump, and by reducing pumping losses by making it easier for your engine to breathe, you can increase HP or fuel efficiency. Air-RAM intakees or Cold Air Intakes with high-flow cone filters. These are available from a large variety of manufacturers, some are CARB permitted, others are not. Cost: $50-400
Exhaust Header: Now we move into a bit more complex area, and whether or not this will provide any MPG benefit depends on a few things, and potentially has legal ramifications. If your car has a catalytic converter (cat) in the exhaust header, replacing it with a header without the cat will increase exhaust flow, possibly leading to more HP and MPG. However, this will increase your exhaust emissions, and in some states such as California, such equipment is not legal. Cost: $150-500
If you put all three of these items on your vehicle, you can probably squeeze an additional (this is purely my opinion based upon my personal experience having done this to one of my vehiclees) gain of anywhere from 1 to 4 mpg.
For body modifications, smooth underbody panels, drag reducers behind wheel wells, replacing side mirrors with cameras and displays, and others can all reduce drag, and increase MPG. I've seen online in forums where people have obtained results greater than a 5mpg addition through body modification on their car or truck. (Addition of tail-cones, etc.)
~Durandal (http://www.wtdwtshtf.com)
One of the great things about the Honda CRX (as you know) is that it does NOT have power steering. With the manual rack and pinion you can key off and engine off glide without any appreciable difference in the feel of the car. The brakes retain plenty of power for a good while, good for one solid jab, or a few touches and can be replenished by gliding in gear for a few seconds. I would NOT recommend underdriving the alternator but the PS/AC should be fine.
There's a nutjob that goes by the handle Basjoos at a couple of forums (mainly www.gassavers.org). He's done some interesting stuff, but it's slightly insane: http://crxmpg.com/basjoosgallery.html
I have to hand it to him, though...he manages to pull out some rediculously high MPG numbers with that beast. You can potentially get a lot more than 5mpg with the addition of fender skirts, grille blocking, and boat-tailing.
This site: http://metrompg.com/ has some interesting things on it, with some decent testing done by the owner.
One of the more interesting cars (to me) was the Honda Civic VX which basically no one but nutties have ever heard of. It was produced only a couple of years in the early 90's (egg body) and had a 105HP V-tech...probably the lowest hp v-tech Honda ever let slip to american shores, and had "lean burn" mode. It could get an honest 50+mpg without a plethora of advanced trickery.
I have posted my oposition to mandatory speed limits before, but I'll reiterate my main points. Clearly, driving 55 instead of 70 on a noncongested highway reduces fuel use. My concern is that on a congested highway, i.e. Houston from 7-9am and 4-6pm (+/- depending on which side of town) will actually increase the fuel usage by reducing freeway capacity, and extending the amount of time cars are sitting in stop and go trafic, and burning gasoline. My work hours are 6am-3pm, and I can sail to or from work in about 15 minutes at these off peak times driving 70mph, and get between 30-35mpg. If I sleep in, it takes me at least double the time, and I am lucky to get 25mpg, meaning I use 20-30% more fuel. I suspect(WAG) that reducing, and enforcing a lower limit(nothing creates a trafic jam faster than police lights)would cause freeways to bog down at least 30 minutes earlier, negating any gains from driving slower. So if the intent of the law was to reduce fuel use, in some situations I feel it would fail. If, on the other hand, the real intent was increasing ticket revenues, it would probably be a success.
I am not against driving slower, but I feel it should be left to the individual, and the circumstances to determine what $ to time tradeoff makes the most sense. For example, while speed often takes precedence on my daily commute, on a weekend drive to the inlaws, I usually slow it down to 55-60, becasuse there is clearly no benefit to getting there faster. However, as happened a few weeks back, a crying baby in the backseat on the way home accelerated the value of time, so I put it on 75.(25mile trip). I think, and I have observed in my own little area, that many people have slowed down in response to high fuel prices without government prodding/force. Modern cars and highways are engineered for highway speeds in excess of 70mph. A well intentioned, but heavy handed law that reduces the speed limit to 55 is not necesary in my opinion,would save far less fuel than many suggest, and would infringe on the individuals rights to make their own decisions.
So how is a 65 MPH or 70 MPH speed limit not "mandatory". Oh, that's right, speed limits must fall into the category of "voluntarily followed" laws. Well, if you put me in charge, I'd enable the ubiquitous traffic cameras found on most urban freeway systems to use photo enforcement. Start slapping people with fines by mail, and watch the world slow down.
Currently, if the speed limit is 55 MPH, people take "creative license" to go 70 or 75 MPH cause what cop is gonna pull you over for 15 MPH over the speed limit when he can nab people going 30 MPH over? When speed limits are set for 65 or 70 MPH, this means many drivers ( a majority in some cases?) will 80 or 85 MPH if not faster.
If you know anything about drag, it grows at a geometric rate with a speed increase. I've seen figures from the transportation department that some vehicles (every one is different) can lose 10% of their fuel economy for every 5 MPH over 55.
30 MPG @ 55
27 MPG @ 60
24.3 MPG @ 65
21.9 MPG @ 70
19.7 MPG @ 75
This means a reduction of 35%! Even if the reduction is only 20% that is still a significant fuel savings, especially if most drivers did it!
Time savings from speeding is usually highly overrated. If you are going 75vs. 55 MPH for the entire length of your route and your commute is 30 miles, you'll save 8.73 minutes each way. This is a large "if" though because in the real world, encountering heavy traffic, accidents, etc. is quite likely. If you do have to slow down, all of your time savings goes down the toilet as the turtle is now given a chance to catch up.
Many of the accidents that cause traffic slowdowns are caused by people jockeying to get one more car length ahead as though there were going to be some sort of prize for finishing. What is the time/economic slowdown caused by these accidents?
I know the time savings seems economically worth it, I mean you saved 17.5 minutes each day. That's like an extra half a sit-com you could watch. But when I see figures like the typical employee wastes 2 + hours at work screwing around (posting on the Doom Beat perhaps?) I think the economy can survive the extra commuting time.
Obviously on trips lasting hundreds or thousands of miles, the time savings could be significant. On longer trips I always see drivers, who have not figure out how to use the "cruise control". They will go 85 MPH weaving between traffic to pass people as if they were in a LeMans race. {Ring*ring} "Oh, wait, there's my cell phone..." Now they're going 60 MPH and all of that time savings is quickly evaporated.
One of the best benefits of driving less aggressively is the reduction in stress. Many moons ago, I drove around "like I stole it". I tailgated, cursed at everyone, and was generally miserable. Slowing down improved my mood a lot. Try it, you might like it...
"So how is a 65 MPH or 70 MPH speed limit not "mandatory"
Clearly it is.... I have no problem with speed limits determined by engineers to be the maximum speed that a road can safely be driven on. These speed limits limit the rights of reckless drivers to impose their risks on others. Clearly you have done the math...by all means drive slower if you have determined that this is the best choice for you. All I'm saying is that you should let everyone else do the same, plug in their own variables, and decide what their optimum speed is for different situations. I think driving slower is a great idea, and as mentioned, I practice it quite a bit. However, don't pretend that it is cure all that will have no negative unintended consequences. It will, and in some circumstances, that will be increased fuel usage, not lower.
Well my problem with 65 or 70 MPH speed limits is that drivers routinely drive 15 to 20 MPH over the speed limit. If engineers have determined the road is safe at 65 MPH, the real speed limit should be 45 or 50 MPH because many (most?) people act as though it is their right to go faster than the posted limit.
Ironically, slower speeds tend to reduce traffic congestion, by limiting the number of cars passing through bottlenecks, and lowering the number of sudden brakes.
They enforce lower limits on congestion-prone sections of London's M25 orbital motorway. There is a variable speed limit, shown on electronic signs on overhead gantries. When traffic starts bunching up at peak periods, the limit drops from the standard 70mph to 50mph or even 40mph. It's not perfect but it seems to work well enough at keeping heavy traffic flowing whenever I go through.
Again, speeds on sections of motorway that are coned off for repairs are now often controlled by "average speed" camera systems, which record vehicles' licence plates as they pass through and send the owner a ticket if their car gets to the end of the controlled section too soon. Works much better than conventional speed cameras, which allow drivers to drive as fast as they like and only slow down when they see one - causing the braking, bunching "ripple effect" that eventually leads to standstill traffic. Admittedly, the price of a clear road is to have Big Brother reading your licence plates.
Anecdotally, now that fuel in the UK costs around $2.30 per litre for petrol and $2.60 for diesel, there's a de facto 55mph limit on main roads (legal is 60) while the majority of drivers on motorways travel at the legal 70mph instead of the 85mph that was pretty common a year ago.
olepossom, you have touched on the biggest culprits....city planning. I grew up in the Minneapolis area and just south of down town there were roads that had all of the lights timed to a certain speed. That speed was posted ("The lights are timed to 38 mph") and only the folks that were from out of town would gun it to the next light only to have come to a complete stop and have all of the folks going 38 mph pass them by. Quite humorous actually.
How about in my current town of Merritt Island, FL where at 4 am the big thoroughfares through the island is consistently stopped cold by someone coming up to a side street and then….turning right (yeh, that’s right many of the streets in this town don’t have dedicated right turn lanes). The road sensors detect the car…think that they want to turn left and then trigger the lights to change, bringing all of the cars on the thoroughfare to a stop as we watch this car make a right turn onto the main street….something they could have done without a light change. Disgustingly stupid. What ever happened to flashing yellow lights on the main street and flashing yellow on the side streets?
Regardless of whether lower speed limits or slower drivers contribute to traffic congestion (I believe they do in certain circumstance especially in the US where drivers don't obey slower traffic keep right laws), but there's a huge problem with the 55 mph speed limit. Its original intent was energy conservation, but speeding is a safety violation with criminal penalties. Rural Interstate highways were built for safe travel at 80 mph, and they can be driven safely at even higher speeds if drivers obeyed the slower traffic keep right laws like they do in Europe.
We have no business criminalizing behavior that's safe. What to do? I don't know. Maybe you could make speeding up to 75-80mph a civil fine like a parking ticket.
Last year I was traveling on a rural interstate highway (two lanes each way divided) where the speed limit was 70 MPH. I was doing 60 MPH, the legal limit for 18 wheelers. I moved to the left hand lane to pass a truck that was going slightly slower. In my rear view mirror I observed an SUV approaching at a high speed. To be polite, I moved back over to the right hand before passing the large truck.
I'd estimate the SUV driver was doing 90 around. As I pulled over to the right, another SUV driver who was tailgating the first one took the opportunity to pass by entering my lane and approaching my bumper at 100 MPH. He cut off the other driver passing my vehicle so closely that the turbulence shook my car.
This driver risked seriously injuring or killing me, my wife, himself and whatever passengers he had on board. And for what? So he could be in front of the guy going 90 MPH? Drivers traveling in the passing lane are a problem in the USA, but maniacs with no regard for their safety or the safety of others seem to me to be a much larger hazard.
Most US states don't have laws prohibiting passing on the right, but it goes together with slower traffic keep right. No passing on the right is strictly enforced in Europe, and people there drive safely at 90 mph or more.
An even better way to reduce fuel use is to mandate 4 day work weeks, and mandate (or provide tax incentives) that companies have workers that can work from home some or all of the time. I work from home currently, and I often find myself donating the time I'd be in a commute back to the company, and still having more time for family / personal use.
Just a reminder, thanks for clicking the "SHARE THIS" buttons (which are available on all our posts) and vote for our work on various sites like reddit and digg. Those link farms help us get a lot more eyes, which means more ad revenue to support the site--it's worth ten seconds to do it, I hope.
http://www.reddit.com/info/6m6xh/comments/ (ENV)
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the challenge of peak oil is not that we will have less oil but that we'll have to get more out of the gallons we do use. viewed from that perspective peak oil is not as dire especially since we already waste so much oil. check out the 170MPG scooter.
Happy Scootering!
http://peakoildebunked.blogspot.com/2008/06/359-hybrid-scooters.html
Have you any idea what a hospital stay costs? Keep an eye on those mirrors.
And hopefully the majority of people will switch to a smaller vehicle or a motorcycle/scooter, making the hazard a bit less.
Amen! I just wish the government would make these importers of Chineese scooters provide parts and service for at least two years. I've got my eye on a Chineese knockoff of the Honda Ruckus.
I have found that not gearing down helps improve my mileage on my standard transmission car. When approaching a stop light, I used to gear down, and let the engine slow my car down. Now I just put in the clutch and use my breaks. I have noticed an increase in my mileage.
That's an excellent point.
Even on automatic, it helps economy to switch to neutral and coast, rather than keep it in drive. However, some automatics do not like it and wear down faster.
Saving tips for bigger cars:
- take a bigger car that can seat all passengers than 2 lighter cars, even thout the smaller cars are more efficeit.
- bigger cars and light trucks have peak economy at higher speeds, between 60mph and 65 mph.
The peak maximum efficiency where the derivative of drag force ballances the idlepower/speed ratio at the highest gear.
My previous car was a manual, and I saved a TON of gas doing this. I always put in in neutral going down hills, or when I saw a red light coming up.
This will be different in a vehicle which cuts off fuel to the engine if it is engine-braking. I have engine-braked down entire mountains after clearing the trip average and seen > 99.9 MPG on the display for some distance on level ground.
I use the coast-to-the-light trick if I have enough warning and traffic doesn't mess me up.
In other news, I drove to work today behind a minivan doing 55 MPH in a 70 MPH zone. At least two other vehicles pulled in behind us in convoy and got off at the same exit. People are getting with the program.
I'm surprised by this...
In my opinion, this is only true if you have an old car with carburator. My VW TDI with electronic injection just stops sending fuel when i release the accelerator, but needs to send a minimum to keep the engine running if i'm in neutral. I'm french and drive a 5 year old seat ibiza (VW design, with a 100HP TDI engine), with 90000m, and i get between 50 to 60 mpg, driving at 70mph (for euro readers, i'm doing around 3.8 to 4.5l / 100km).
The greatest danger to life and limb on the highway is the difference in the speeds of the vehicles. Anyone doing 55 mph in a 70 mph zone, where the actual speed is closer to 80 mph, is putting him- or her-self in a heap of jeopardy, not to mention other drivers. This topic was recently covered by a local TV station, and the videos of other cars whizzing by the guy saving all that fuel were just plain scary. In addition, having an eighteen-wheeler pulling up behind you at an approach speed of 20 or 30 mph, with nowhere to go but a busy left lane, is going to put the trucker, the faster cars in the left lane, or the fuel-saver that much closer to the pearly gates. Getting 70 mpg is great, especially to a guy like me getting 17 mpg, but it seems a bit selfish when the increased hazards are considered. IMHO, these techniques are interesting to explore, but should be limited to tracks or labs, not the real-world highways.
If the government wants to take matters in hand and lower all speeds, great. However, to get those speeds down, there will have to be rigorous enforcement, which isn't likely given today's state budgets (which will no doubt get worse with less driving, less gas consumption, and fewer tax revenues).
Generally caused by the person who is breaking many laws, speeding, passing illegally on the right, changing lanes without signaling, following too close, driving recklessly...
Yeah, you are selfish for creating a hazard by speeding or driving aggressively. That guy is also subsidizing you your "self less" act of speeding by reducing demand.
Photo enforcement using traffic cameras. Revenue generator. Are you serious about losing tax revenues through using less gasoline? Hello, price of gas far outstripping taxes place on it... Well if your that worried about propping up your states budget, why don't you add some lead weights to you car to further reduce your gas mileage?
Didn't mean to step on your rather tender toes, but who said I was speeding? As they say in Clue, are you making an accusation?
I think my comments are valid. If you come up on one of these guys going 43 mph (see the chart) while you're driving 70 mpg (posted speed), you might come to the same conclusion. I hope that explains my position, without being accused of reckless driving!
Does going against the grain on this forum constitute grounds for unfounded accusations and verbal abuse? I didn't think so in the past; hope I'm wrong now...
Collin Riley
If I'm tender about this, it is mostly because I've been fighting this battle for seven years while hearing people gripe about high fuel prices the entire time. Aggressive driving is dangerous and wastes fuel. Here we have something that could reduce gasoline demand by 20-30% tomorrow without changing anything else. No carpooling, no bicycling, no walking, no buying a new vehicle. Less demand means lower price with the added bonus of increased safety.
I agree, anyone driving 43 MPH when the legal limit is 70 MPH is causing a hazard and in many localities is probably breaking the law. The case you cite is most certainly the exception. A more realistic example is someone traveling 60 MPH in a 70 MPH zone while being passed by people going 90 MPH. I see this type of driving whenever I drive on the freeway.
Whose toes are sensitive? If you've taken offense, I apologize. My acerbic side is genetic (I come from a long line of sarcastic smart asses). I get a little worked up when I get feed such a specious argument as, "We should waste fuel because if we didn't, our state tax revenue would be lowered".
Thank you for your reply.
On the last point, when there is less money available from gas taxes because less gas is sold, then there is less money to fund the patrols needed to inforce lower speed limits. My statement about taxes wasn't a support for more taxes or a desire for less taxes (a tax idealist I'm not); it was just an observation, such as: 2 minus 1 equals 1. If alternative, and affordable, methods of enforcement can be found, so much the better. However, IMHO we are faced with years of shattered state budgets, and state patrols will have to fight for every dollar of funding, right along with everyone else. I don't count on the general public showing speed restraint.
I would prefer if police were investigating real crimes like theft and murder instead of trying to enforce traffic violations which they themselves regularly violate. As I stated above, I think that camera technology is the way to enforce speed limits. Police have never been able to cite enough people to have a lasting effect on driving habits anyways.
That's because there's the leadership in this country (like the voting population) sucks. As I said above, everyone cries that gas is too expensive and how they're being screwed by big oil or whatever, while they jam the accelerator so they can brake at the next light. Day after day we discuss this techno wizbang fix or that wonderful sci-fi fix or the merits of this economic plan or that. Anything that will allow us to keep happily motoring along. Meanwhile, 20-40% of our demand is simply a result of the "I've gotta get one more car length ahead" mentality.
That so much resistance exists amongst Oil Drum readers to conserving fuel through changing driving habits, makes me very pessimistic that much will change. Meanwhile, I'll keep cycling, driving "nicely" (I refuse to call it "eco-driving"), and trying to reduce my electricty and nat gas consumption. Not to save the planet, but because we're all gonna have to make due with less in the future.
They cite enough people in the UK to affect behaviour.
Speeding fines are a major money making device. Uninsured drivers are immune, but anyone with money is a target, for even a few miles and hour over the limit when the road is clear.
Speed cameras are everywhere, as are CCTV cameras on city streets.
Accidents may have been reduced somewhat, but crime in the streets has not.
Of course, although the overt purpose was the reduction of crime, control and surveillance is the effect.
High gas prices on their own will reduce speeds. They will also lead people to choose the most appropriate size car for their use.
Be careful how you give away such liberties as remain to you.
Can you explain why uninsured drivers are immune? Do you mean drivers who are not registered? Here you must show proof of insurance in order to register your vehicle. If you let said insurance lapse, your insurance company notifies the Department of Motor Vehicles who send you a nasty letter threatening to revoke your drivers license. Of course drivers who have no registration or insurance don't have to worry about unless they get stopped by the police.
The cameras I am referring to are already rolling on freeways all over the country and are used to monitor traffic conditions. I've never considered the right to speed nor to be free from being videotaped in public a "civil liberty", but I'm sympathetic to your point. I trust my local government only slightly more than I trust the federal government (which is not very much at all).
The drivers I am talking about don't bother with anything. The police when they stop them can't do anything, as the jails are full so it is a waste of time taking them to court.
We have roads which are 30 in some stretches, and 40 in others, and it is often not clear which is which as they are poorly marked.
If you get caught you will get a £60 fine even if you are a couple of miles and hour over the limit, your license endorsed and your insurance is likely to rise, although some insurers are considering changing this as speeding offences used to correlate well with risky driving, but they no longer do, being more like a game of hazard.
If you were unlucky and staying away from home, in a hotel, say, and drove into a work-place, going back to the hotel lunchtime then back to work and returning, and were unaware of a stretch of 30 mph in a 40mph longer stretch, you could get 12 points and loose your license in a day.
If you want to be governed like that, great.
Is there someplace where people don't complain about bad governance, traffic, law enforcement, jails etc.? Cause that place definitely ain't here either.
I think it must be WT's land of elves and fairies, with unicorns grazing in the pastures, tended to by members of the Texas Communist Party because they obviously can have endless cheap fuel without affecting the environment.
I've been to many countries and always found complaints about the government, usually they tax too much or don't spend enough on health, education or have too many rules or there is chaos... It's in people's nature to want more.
But I think it's true that in the UK the police are burdened with so many targets and form filling that they tend to go for the easy law abiding target (speeding motorists) rather than the hard to catch and successfully prosecute criminals.
An example, in one London borough the income from parking fines exceeds £100 million per year. Note the police do not issue these fines but local government.
Celticoil is right.
Moreover, for number of cars 65mph is more efficient than 45mph.
The speed limit should not be thouth of as Maximum , but also as minimum 45 km/h.
Small compatcts are better of at 55mph, heavier cars, sportcars and cars with high length/crossection ratio will improve economy by by speeding up a little.
My wife aveages 14mpg on the same minivan that I can average 22mpg, because she drives too slow and does not force the automatic to upshift whenever possible.
Mercedes 300TE has pretty flat consumtion curve all the way to 100mph, then it decreases about 20% to the 130mph.
Every care is different, and on many, going 45mph means wasting gasoline. And if you do that on a highway, you are irresponsible and dangerous.
About what?
Are these same vehicles that are more efficient at 65 MPH as efficient at 80 MPH cause that's how fast people drive on the freeways where I live.
Source please?
You keep saying 45 MPH. Who suggested driving 45 MPH? If fact, I said:
I agree, anyone driving 43 MPH when the legal limit is 70 MPH is causing a hazard and in many localities is probably breaking the law.
If you have studies that show a statistically greater risk to drivers that drive beneath the speed limit, please provide them. Otherwise you are engaging in pure speculation.
Not to worry, the 18 wheelers will be gone soon....
Given the hierarchy of needs, what do you think people are going to spend their remaining fuel on: commuting solo, or having food trucked to them?
I expect to read about gasoline conversions of truck diesels soon.
I have been doing this in my 2007 VW GTI. I am getting around 28 mpg in mixed driving (EPA is 22/28). I get in the right lane, and set my cruise control for the actual speed limit. This has saved me a ton of gas. If I need to pass, I've still got the turbocharger on standby, ready to kick in.
Also water or alcohol injection on the intake.
Looks like 35 mph is the best fuel milage
http://www.drive55.org/
Cell phones can be used to report speeders ....
So 55 mph could work
I would rather people didn't fart about with phones while driving.
Definitely not on my cars.
All my cars that I have driven have best efficiency on highest gear or overdrive. That is not possible at 35mph.
Hypermiling is fun... if you're not in traffic. I, and I'm sure many others, were doing it (as a driving style, not vehicle mods) long before the word was coined. But in traffic there are limits to what you can do that won't cause others to burn more gas, so I do a "modified" version which just saves modestly.
yeah, I'm familiar with Jevons' so-called paradox and realize I'm subsidizing the hummer drivers by so doing. And I drive a lot less than 1000 miles per year anyhow, so the absolute savings are small. Still, as I say, it's fun. A cross-country trip with little traffic in a hilly area with a lot of turns actually becomes an involving experience rather than a bore.
Relatively efficient cars are not necessarily expensive. The last time I went shopping, I sought out a car with cosmetic damage which would not affect its safety; cars that are normally considered "salvage" vehicles. I picked up a 2002 Hyundai Accent with 75k miles which had been sideswiped and then vandalized; one side is striated and scarred, and the locks were punched out, the sunroof gone, the gear shift knob gone, other minor stuff. But the engine, brakes, airbags etc were all still perfectly functional. I paid $1100, and on the way home another $27 to have the hardware store cut me a square of acrylic plastic which I screwed over the sunroof hole with a gasket. I didn't bother to fix the locks or repair the cosmetic damage. I average 43mpg in mixed traffic and higher at other times. Again, I do it because it's fun and because I find it aesthetically unpleasant to pump CO2 into the air.
I'd recommend it: getting a cheap car with cosmetic flaws and a 5-speed gearbox, and using hypermiling techniques to the extent you safely can without holding up traffic. The best hypermiling technique, though, is simply stay put. This is more of an option that most people think it is.
It's also more environmentally responsible to purchase a used vehicle instead of a new one..
Reduce (the size of the vehicle, the miles driven, your speed)
Re-Use (buy used, fix it don't toss it.)
Recycle (Part off car to fix others on the road that still run, then literally recycle by having the scrap-yard melt it down into railroad rails.)
My 1994 Geo Metro can get 50mpg ... I paid $300 out of the wrecking yard
Great! BTW I recently read something about one going for over 7K on ebay. I'd still be driving my 93 Suzuki Swift if it hadn't been totaled by a large speeding van while I was stopped at a traffic light. I had to trade up to a gas guzzling 2000 Ford Escort with a 5spd manual transmission. Fortunately weather permitting I can bike the 4.5 miles to work so I have been driving it less and less.
Ride a Bike or Take a Hike!
Great post. I agree. We have a 95 Grand Am with a 2.3 liter engine and a five speed. Both engine and transmission have been replaced. The car has 275,000 on it. But when I try to use all the energy that I can in forward motion, some nice things happen. Driving back and forth to work together over a two week period this spring, with cold starts, a 13 mile one way commute in mixed driving we averaged 46.9 mpg.
Driving at high speeds hurt our mileage more than any other single thing. Air conditioning will knock 2-3 mpg off, but it is probably worth it.
I have a great time trying to get the most out of a gallon of gas, and I think it keeps me alert as I am always watching the traffic a little closer for a light changing etc.
Two words: Lane discipline. If your going to go slower, get in the outside lane. If your going to go faster and pass, go to the inside. Once your where the traffic is again emptied out and you past, for pete's sake move over. Don't get beside someone on the inside lane and let traffic back up behind you. If everyone would practice decent lane discipline, congestion and efficiency would be greatly improved.
RC
Amen to that pet peeve.
I am sick of weaving around slowpokes in the left lane. Hyper-milers stay to the right please [USA lanes]. Honestly there are so many people who don't remember the road rules, like PULL UP into the intersection prior to making a left turn at a light. The left turner behind you would also like to make the light, thank you very much.
I have driven some stretches of I-5 between Vancouver, BC, and Portland, OR, many times over the past couple of decades. Sometimes a dozen or more trips a year. The posted speed limit in parts of WA is 70 mph for most vehicles and 60 mph for trucks. I usually drive at the 60 mph mark to save on fuel and for a more leisurely cruise, though at times I would go faster, but rarely up to 70.
Even in the recent past, with my speed set to 60, the tractor-trailer rigs would simply blow past me. The drivers were clearly intent on the 70 mph limit instead of the 60 mph one. Based on my best estimates, many big-rigs cruised along at about 67 to 70 mph, if not a little faster.
In the past few months, this has changed dramatically.
Now, as I cruise along at 60 mph, many trucks only pass me slowly, and some just creep past. I'd say that, along I-5 at least, there's been a downward shift in general trucking speed by about 5 mph. Most rigs seem to be doing 61 to 65 mph instead of 67 to 70.
This is purely anecdotal, of course. The change, however, seems quite dramatic to me. The slower truck speeds were a dominating character of my most recent I-5 drive just this past weekend. The obvious suspicion here is that truck drivers are reducing speeds to save on fuel.
Nevertheless, at 60 mph, I only passed a single truck over 275 miles of road (excluding on-ramp mergers). The truck drivers haven't adopted 55 (yet?).
-best,
Wolf in YVR BC
PS. On my most recent trip, gas prices were generally $4.20 to $4.39 a gallon for 87 octane across much of the interior of western WA, with diesel around $4.90/gal.
It is also quite noticeable in the Toronto area. Previously, some of these guys were like Mad Max-these giant trucks were in no way constructed to be driven (safely) at 80 mph in a rain/snowstorm. IMO the limits should be 70 mph for cars, 55 mph for trucks (and the cars would still be less of a menace).
I had a friend who used to commute from Boulder, CO to Denver (roughly 55 miles) three to four times per week. He worked as a surgical assistant and would routinely arrive 60-90 minutes before he was required to be there so that he could relax and read the newspaper. He would show up early because it was his in his personality to be punctual. What was also in his personality was the need to drive like the biggest a*$hole in the world. Tailgating, cursing, gesturing, speeding, passing illegal, talking on the phone, he would do it all.
I once asked him if it was worth the 15 minutes he saved (or didn't save) to risk his life and the lives of other drivers around him. Maybe, I opinined, if he didn't speed and drive like a jerk, he wouldn't need the extra time to wind down. He reflected for a moment and then said, "But that's the way I drive!"
The automobile has become out personal little transportation bubble that allows us to ignore the needs or safety of others outside of it. No a lower speed limit won't solve all of the world's problems, but educating people about the consequences of bad driving might save some energy and better yet some lives. Automobile accidents cost the economy billions of dollars each year in insurance and medical costs and cause people to spend more time sitting in traffic.
It might even allow a few more drivers to commute with a smile instead of a chronically clenched jaw.
It seems to me that people drive on the road a bit like on a race track. It doesn't matter how fast Kimi Räikkönen drives, Lewis Hamilton is going to try to pass him. It doesn't matter how fast I drive, everyone will want to pass me. Maybe Kimi can drive so fast Lewis just cannot pass, maybe my car is mechanically capable of speeds so very far above the legal limit that although everyone will still want to pass they won't dare, but people measure progress by how many people they passed, not by distance covered and certainly not by fuel efficiency. Observe how desperate people are to pass at unsafe/illegal/dumb places when an excellent space for passing is seconds away and we're all headed for a stop at the intersection just ahead anyway.
Anyway, I hang out in the right lane and mind the fuel consumption display, and everyone passes me, and even in my younger and crazier and more wasteful days I never drove fast enough that I wasn't being passed often, anyway.
Graywulffe,
you are right. I drive a SMART Diesel from 2004. After the recent price hike a lot of the bigger Mercs and BMWs started crawling behind the trucks at about 90 km/h. I often have to overtake them to get ahead. I pay about 22-25 Euros for a fillup of 15-18l and get as far as 450 km with one tank of Diesel. They have to pay 80-90 Euros for 45-60l to go 500-600 km.
Traffic is much smoother now.
Best Regards from Hannover,
J. Dähn
Hypermiling is the general state while driving a Honda Insight. When first commuting between Asheville, NC and Charlotte, NC I was averaging over 70mpg. The little car gets most of its efficiency because of low weight (1875 lbs with AC) and some because of electric assist. It is extremely sensitive to mileage raising/lowering conditions such as type of tire, fuel octane and quality, tire pressure, tailwinds, air temperature, engine tuning, weight of passenger, etc.
Unfortunately, now I'm forced to burn 10% ethanol and currently have non-low rolling resistance tires and am pressed to get 60mpg. The tires account for about half that loss and the ethanol the other half. Am getting the low-rolling resist. tires again soon and expect mileage to be in the lower 60s. Cooler Oregon weather lowers the mileage too.
Best hopes for getting rid of 10% ethanol gasoline, or at least allowing the consumer a choice in the matter.
It's 80 mph going down the Rockies toward Albuquerque.
Heh. I tried following my cousin in his Silverado 4x4 Crew Cab from Farmington to ABQ on US 550 last spring. He held it steady at a solid ton-up.
I let him go at that speed, but I caught up to him at the gas station in Bernalillo.
"solid ton-up"? Translation to something less idiomatic?
ton-up?
Accelerating your vehicle to over 100mph.
http://www.urbandictionary.com/define.php?term=ton-up
Assuming a constant number of miles being driven each year, the gain from getting an SUV driver into something smaller and achieving a 17.5 mpg to 35 mpg improvement saves twice as many gallons as getting someone already in a 35 mpg vehicle into something else and "hypermiling" to get 70 mpg. At least for the US, low-hanging fruit, and all that...
Here is a list of some things that can increase gas mileage, including Durandal's previous comments.
SAVING GAS
1. TIGHTEN DOWN GAS CAPS - Four clicks
2. Stop road rage – racing
3. Avoid drive through
4. Fill up in the morning – gas molecules maller
5. Check Tire Pressures - Check once a month when tires are cold
6. Good air filter - replace and/or clean on a regular schedule
7. Coast when possible
8. Use overdrive
9. Underdrive pulleys- These are lighter weight and larger pulleys that you place on your power steering pump and alternator in order to decrease drag on the engine. This means more power to the wheels, which means either more pep to go, or better fuel efficiency. Cost: $70-140 (I recommend AEM brand) (Alternately, if you have a small car and strong arms, you can simply take the belt off of the power steering pump completely. I've done this before.)
10. Air Intake Sytems- Your engine is like a pump, and by reducing pumping losses by making it easier for your engine to breathe, you can increase HP or fuel efficiency. Air-RAM intakees or Cold Air Intakes with high-flow cone filters. These are available from a large variety of manufacturers, some are CARB permitted, others are not. Cost: $50-400
11. Exhaust Header: Now we move into a bit more complex area, and whether or not this will provide any MPG benefit depends on a few things, and potentially has legal ramifications. If your car has a catalytic converter (cat) in the exhaust header, replacing it with a header without the cat will increase exhaust flow, possibly leading to more HP and MPG. However, this will increase your exhaust emissions, and in some states such as California, such equipment is not legal. Cost: $150-500
12. Body Modifications: smooth underbody panels, drag reducers behind wheel wells, replacing side mirrors with cameras and displays, and others can all reduce drag, and increase MPG. I've seen online in forums where people have obtained results greater than a 5mpg addition through body modification on their car or truck. (Addition of tail-cones, etc.)
13. Synthetic Oil: ie Amsoil or equivalent in - engine oil, transmission, packed in wheel barings, transfer case, rear end. Could increase mileage 4 to 6 mpg and saves money with fewer oil changes.
Please add and post or email me with any additions
THX
In case you need to SEE why some of the better synthetics can give you better mpg here are a couple of videos. For more info on the better synthetics out there try the "Bob is the Oil Guy" website. Also, I like to visualize driving with an egg between my foot and the accelerator pedal when driving to cut back on "mashing on the gas".
http://video.google.com/videoplay?docid=1712299263246216338
http://www.royalpurple.com/rp-testing-summaries.html
A simple way to improve your MPG, your safety, and the safety of others on the road is to pretend you have no brakes. The more congested the road, the larger the benefit. By driving as if you have no brakes you will find yourself looking further ahead and anticipating changes in traffic flow. You will quickly become an expert in predicting what other drivers will do, both the good ones and the stupid. You can reduce the amount of braking by upwards of 75% and your average acceleration rate will drop. The chances of another vehicle involving you in an accident are greatly reduced. Like any good idea, this one can be taken too far. But, it is easy to do and will, over time, become a habit.
Also, as one of the first owners of a 2000 Honda Insight I was amazed at how my driving habits changed because of the feedback I got from the MPG gauge. I was puzzled as to why this simple technology was not standard equipment in all vehicles. Eight years later and with $4.00 a gallon gas, I'm even more puzzled.
4, 10 and 11 are way off base. Underground temps don't vary much through the day, so it won't make much difference when you fill up, even if gasoline expanded significantly (which it doesn't).
On a gas engine, unless you're at full throttle, the air pressure is determined by the throttle, not the air intake. Cold air burns more fuel (at constant volume/pressure) than hot air, so hypermilers make HOT air intakes, not cold.
Catalytic converters have very little back-pressure, so they have little bearing on anything other than emissions. Removing it is an anti-social statement like removing your muffler, except mufflers have more back-pressure and hearing loss doesn't cause deaths like respiratory disease.
More importantly, low exhaust restriction can hurt mileage. With the right amount of pressure, you get an effect like exhaust gas recirculation. That extra inert gas in the cylinder reduces your pumping loss while increasing the amount of gas you're heating. Too much pressure increases the exhaust pumping loss, so it's a balancing act... one the manufacturer already did for you. So leave the intake and exhaust alone for the best mileage.
The real hypermiling tricks are:
1. SLOW DOWN!
2. Drive less, but combine trips when you need to drive (cold engines are much less efficient).
3. Accelerate slowly, never floor it (it causes a rich 'power' mixture).
4. Decelerate slowly, by anticipating what's going to happen and coasting instead of braking.
5. Going to wait more than 5-10 seconds? Turn it off.
6. Minimum tire pressure is the manufacturer's ratings, but better to sidewall.
I didn't realize that the Aptera was going to have solar panels on the car.
http://en.wikipedia.org/wiki/Aptera_Motors
that's awesome. it's getting easier and easier to envision win ten years that new cars won't have a gas tank.
Maybe I'm too young, but what's the point of driving slower? I can afford gas and my time is much, much more valuable to me than a few dollars of gas a day. Are there really that many people living on the edge that they will waste their lives away by driving @ 55 mph?
Maybe I'm too old, but I enjoy driving. I see no reason to hurry it along... :o)
-best,
Wolf in YVR BC
Oh, the bicycle is where I hammer away at max power. That's where it makes sense. Also, get the stopwatch out. How much more time does the bicycle actually take compared to the car? The car sure seems awesomely fast on the highway, but stopped at a red light is the same speed either way, so the real difference is rather less dramatic on the shorter trips. Can you actually even see a difference in travel time driving as fast as possible vs. slow and careful in the noise of random traffic delays?
Let's look at a commute.
Things to notice:
Your savings on the "slow" portions of the trip are double the savings on the "long" portion of the trip.
Your overall time savings is actually pretty good in this scenario, about 20%.
In order to save 4 minutes in the "long" portion of the trip you would need to go nearly 100mph.
If you went 10 under for only the freeway section you only "lose" 3 minutes.
Things to take away from this analysis:
From a time standpoint you are better of speeding when the speed limit is low, which most people don't do as much because it is dangerous. The speed limit is low (in most places) for a good reason.
Claiming that you're speeding because your time is so valuable that you daren't waste it is disingenuous because if your time was that valuable you wouldn't be driving. At the very least you would have a driver so that you could be working while being transported.
--
JimFive
Here's a non-representative Report from Europe:
I commute to work 28 miles per day (single trip) with my 130 hp Seat Ibiza TDI Diesel (thats the same Engine and Chassis as in the Volkswagen cars, it just looks differently and is cheaper :-). About half the time I spend in the respective city-traffic, the rest is highway cruising with the occasional traffic jam.
Though the pump prices here in Germany have not gotten up as dramatic as in the U.S. due to the high taxes here, my commuting-sport changed recently from "How fast can I get to work?" to "With how many litres per kilometer can I get to work?". BTW reading the oil drum for the last two weeks was a major factor in that shift :-)
OK, so lets come down to the numbers:
My current record (morning business traffic, but no jams) is 3.7 litres per 100 km (thats 64 mpg for you non-metric reverse-thinkers). That was achieved with restricting myself to 55mph on the highway, braking as less as possible and occasionally driving only 20 yards behind a truck on the highway (*that* reduced my current fuel flow about 40%!).
Driving "normally" with no special mind for hypermileage, which translates for me to around 90 mph on the Highway, gives me around 50 mpg.
Driving "fast" to minimize my time to work, with top speeds of 120 mph on the highway I'm getting around 38 mpg.
Based on these numbers, I forecast a considerable amount of demand destruction in traffic, which will probably come in waves as it is largely psychologically motivated, and the commuters psyche cringes always when the next "price level" is reached (like the next full Dollar per gallon at the pump).
When the U.S. reaches the current European price level, which is around 8-9$/gallon, you probably want to get a car mix look roughly comparable to what we have now. Start thinking about Seat Ibizas, guys ;-)
I also have an ibiza but with the cheaper 100HP, and the figures are the same here in france. Personal best of 3.8l and worst of 7 ( 190kph, the max the car can do).
And clearly, the smaller the car, the bigger the mpg. Start thinking about weight reduction. ;)
The trouble with this method of travel is that when you go, you have to take a tonne of steel with you. Whatever you power the damn thing with, it's never going to be very efficient to have a person drag a tonne of steel around with them.
What we need is some sort of mode of transport where you only have to drag 10kg or so around with you. Wouldn't it be lovely if someone invented that?
Or perhaps we could have several tonnes of steel but carrying dozens of people, that'd be good, too.
I really hope someone comes up with these inventions soon.
For the curves
Skoda Octavia TDi Diesel - 2.0 VW TDi originally 140hp but now chipped to a claimed 180 (probably nearer 160 for real).
(MPG = imperial gallon)
Town - 45MPG average
50 - 62 mpg
65 - 55 mpg
70 - 48 mpg
75 - 46 mpg
100 (oops) - 45 mpg
As for service costs (cambelt @ 100k) I have a local specialist who will do it for under £70 which is roughly $140. If anyone charges more then they are fleecing you.
I remain unconvinced that spending £20K on a prius is better than spending £10K on a decent Diesel car.
I decreased my fuel use by 10 percent when I lowered my speed by 10 miles per hour while crossing Tampa Bay each day when I lived in Florida. My current commute amounts to 100 miles each week. I carpool with a coworker when we are both in town. We've discussed riding bikes but about 30 percent of the commute is not bike friendly. I've been thinking about buying a scooter. We'll see.
Just conquer the road. Others will follow, car drivers will adapt, some even might follow suit. Sooner or later there will be less cars to deal with.
From the article: "... using SHM of IG14 and TPS of 18 ..."
Huh?
I guess looking into the future we are all going to be using less fuel so its either hypermiling or get a hybrid that does it for you. If you can capture most of the energy from braking then reuse it the need to drive like you have no brakes becomes a little less pressing. And it's not just electric hybrids that are coming.
http://media.cleantech.com/2929/artemis-hybrid-heddat-dd-digital-displac...
Everyones going to be driving some shape or form of a hybrid in the future. Once oil hikes itself over the $200 mark the economic hit of driving anything that can't recover some of its energy when braking will just be too painful.
Perhaps we have stumbled upon the inverse operation of JEVONS paradox: As the economy tightens, many truckers are realizing there's no need to speed as there won't be another load for a couple of days. Fewer and slower 40 TON rigs chasing you down the highway is a bright spot for the times of necessary driving.
Hypermiling?
That is soooooo 2007. Let me tell you: Hypermiling is for boys.
Let's do some Ultra-Miling.
Go!
I tried one of those Barchettas about a year and a half ago. They aren't safe. If you attempt to turn while pedalling, your heels hit the front wheel and you're at risk of falling over.