Slashdot Mirror
Japanese Mileage Maniacs
WY writes "Bloomberg reports on the quirky world of Japanese hybrid car hackers: 'Toyota Motor Corp. says its Prius gasoline-electric hybrid car gets about 55 miles to the gallon, making it one of the most fuel-efficient cars on the road. That's not good enough for Takashi Toya.' He managed to reach as high as 115 MPG. He is one of about 100 nenpimania, Japanese for mileage maniacs."
We have people who do the same thing here.. see http://en.wikipedia.org/wiki/Hypermiling
Well, on the way up, the fuel efficiency drops. But you build up potential energy, so you hardly use any energy when the car goes down. Any braking power is passed to the batteries. Driving with my dad's petrol car in mountainous regions in France and Italy, I was always surprised that I managed to get a mileage better than regular (probably helped by the fact that the average speed was lower). The first rule of fuel efficiency is: BREAKING IS FOR LOSERS. If you have to brake, you're not good at anticipating very well. Cross-road or round-about coming up: lift you foot from the peddle. Second rule: KEEP ROLLING. You must make sure you keep on roling. If a traffic light is coming up, I may brake well before the traffic light, then roll along. In all likelihood, the light is green when I reach it, and I may have left a speed of 15 miles per hour. If I had stopped, I would have been slower too, because I'd have to start from zero. It is one of those things people fail to understand (just like: the fastest way to overtake another car is to keep a distance from him (much safer too), instead of tailgating. You can see the opportunity for taking over earlier, you can start making speed, if it doesn't work you break, if it does work you're having a first speed difference in comparison to a tail gater). Lastly, I may drive behind a truck (we have laws here that forbid them to pollute too much so it is OK). Saves up to 10% (more if I were closer, but as long as we don't have a connection between braking and distance control, that is out).
Bert
This is what I have always been told, but I just googled it to check, and it looks like it is an urban myth in terms of black-letter law. The police often consider it dangerous and may ticket you for reckless or negligent driving, which you could then dispute in court. In some states it IS illegal to ride a motorcycle barefoot. Driving barefoot is illegal in some other places, such as Hong Kong.
You do realize that only 11% of Japanese land is arable don't you? There are a lot of mountains in Japan. Perhaps it would not be possible to achieve such great millage driving through the Rockies in the US or the Minami-Alps in Japan, but the Rockies are only a small portion of the US, and everything between the Rockies and Appalachian is essentially flat.
Heck, all the land speed records are set in America for a reason, completely flat and no resistance.
inaccurate data: "electric cars do not get great gas mileage at highway speeds because of the power required to keep the car at 60+mph."
I hate to see comments like this. If you have an electric car, there is no gas, and hence, no "gas mileage". This type of comment permeates the media and contributes to the drivel that totally mushes up the real facts of what goes on in engineering and science.
By 2010-2012, I predict the newer faster charging and less expensive batteries being tested now will give us an all electric or hybrid which is charged up at night on reduced rate power off the grid, and which can run 200+ miles before a recharge, or the onboard gas/diesel needs to come on.
Custom shops in the Los Angeles area will mod your Prius or Highlander hybrid today with double the amount of batteries or more, so you can go most of the day on batteries. The ONLY THING REQUIRED IS DOLLARS. It is doable and effective today. It is not yet cost effective or Toyota would be doing it now for retail sales. The minute the battery cost drops, Toyota will easily supply the extra capacity.
From your own linked article:
"The guidelines specify that the car must be appealing to buyers and easy to mass produce -- warning that concept cars or "science projects" won't qualify.
The vehicles will compete in real-world driving tests, in two categories -- mainstream (four or more passengers and four wheels) and alternative (two or more passengers and no requirement on the number of wheels)."
These former record holders in the US achieved ~110 mpg in a Prius.d .htm
http://hybridcars.about.com/od/news/a/100mpgrecor
http://www.post-gazette.com/pg/05220/550484.stm
One of them achieves 59 (US) mpg in a non-hybrid 2005 Honda Accord by adopting crazy hypermiling techniques. See http://hybridfest.com/MotherJones.htm.
Part of the reason that there aren't many diesels on the road in the US is a lack of clean diesel in the US that is available in Europe. I don't remember where I originally read that but it remotely makes sense. Overall though, you're right. There is no real reason that the majority of cars available in Europe shouldn't be available in the US. When I move back to the US (I'm an American living in Prague), I may just take a car with me.
When I tell an object to delete this, am I killing it or telling it to kill me?
The US gallon is only 80% of the imperial gallon - it's not clear which units they are using. FWIW, I've got 47mpg (imperial) over 25000 miles in my Jaguar X-Type diesel without doing more than roughly keep to the speed limits, so I'm not overly impressed whichever units are in use.
I agree completely, almost.
In my case for example I drive a 911, which is neither remotely fuel efficient nor inexpensive to maintain -- but it has a lot of the same disadvantages as a smart car so bear with me. It's lousy for transporting even moderately sized items, you can't haul a boat, or fill it with relatives, or bricks, etc... While I knew I'd love the car I thought I'd *really* miss having a larger vehicle. Turned out its not the big deal I thought it was.
Sure I *could* own a 2nd vehicle, but it turns out I only actually really need one half a dozen times per year. (I think not having one makes you learn to "need" it even less.) But on those occassions I really do want one I just rent one. I also use the various delivery services available when buying furniture, etc. And occasionally use couriers to ship mid-size items that don't fit in the car. I spend around $800-1000 at most per year on rentals and these delivery services, which seems like a lot at first blush... but its nearly half the cost of insuring a second vehicle, and I don't have any maintenance expense, no lease expense, no capital tied up in a depreciating vehicle, and I don't have to worry about having a place to park it either.
Even if ICBC halved or thirded insurance on '2ndary vehicles' I still wouldn't have bothered getting one.
I recognize that this won't work for everybody, but I'm surprised at how painless it turned out for me.
Another option is Temporary Operation Permits, which are also a bit of a pain in the ass as you have to buy them for each date you want to drive, but they provide a decent option for someone who wants to own a vehicle and only drive it a couple times per month. (And maybe keep a storage policy on it if its worth anything.)
All that said, I too wish ICBC let you have multiple vehicles under a single policy, paying the price for the most expensive vehicle to be covered, so you could drive the one you want when you want without hassle or paying multiple times. One can only be driving one car at a time after all. I guess it would have to be a little higher for each additional car to cover storage/comprehensive on each of them.
Yet for all the complaints about ICBC and the 'public insurance company' we've got it pretty good. People always say... "ooo look at how much cheaper insurance is in AB, we should privatize!" Vancouver driving is more like Toronto than Edmonton -- and if you think BC is overpriced you've never tried insuring in ontario. I lived a year there while in university - I had an MR2 (a $5k car at the time) - the best price I could get for remotely decent coverage was $5500 per year. I didn't drive that year.
Do note that this is entirely impossible. The Prius transmission is the hybrid system. It neither resembles nor behaves like a conventional transmission - it is far more mechanically simple and has far more electronic control.
Note that the Prius hybrid system also replaces the starter and the alternator as well, and (from the 2004 model onwards) also runs the air conditioning.
Yes, although engine efficency also plays a big part. The Prius uses a small engine running on the more efficent Atkinson/Miller cycle. The 72HP 1NZ-FXE in the Prius would be undersized for a car of its size, but it's fine with the electric assist.
It's also a two-door compact car. The Prius is considerably larger - perhaps you should be comparing the VW Polo to the Honda Insight, which gets 65-70mpg.
Your Citroën AX is a 650kg 2-door supermini that would be a deathtrap in a collision with anything of any size. Why the hell you would compare it to a 1400kg Prius (which is a 4-door "large family car") is completely beyond me.
You said two things there - 50bhp and diesel. Diesel contains 15% more energy per gallon than gasoline, making any "MPG" comparisons entirely pointless from a carbon-emission standpoint.
Moreover, you also said 50bhp. That's redicolously underpowerd, even for your 650kg Citroën. Forget about having an automatic transmission on a vehicle like that, and you'd better be easy on the clutch or you're going to be in stall city.
Ah, more hybrid misnomers. If you don't understand the battery technologies involved (Ni-Mh in current models), don't comment. Ni-Mh is not "environmentally-disasterous" - in fact, the Ni in the battery is so valuable that Toyota pays a $500 per pack bounty for recycling.
As for the "overcomplicated drive train", the Prius transmission has 12 moving parts, not one of which is a friction or wear component. In the past 5 years, I have never read a single account of a Prius transmission failing mechanically. The same cannot be said for manual or automatic transmissions, which fail all the time because they incorporate wear components (clutches/clutchpacks, syncromeshes, etc) and (in the case of an automatic transmission), high-pressure hydraulics.
This is the typical European Slashdot hybrid idiot post. I've seen it far, far too many times. The post points out how a much smaller, much less powerful diesel-powered vehicle can achieive results similar to a hybrid. Then they top it off with some nice myths about how hybrids are complicated (they aren't - Toyota's Prius is in fact mechanically simpler and far more reliable than a conventional vehicle), bad for the environment (somehow, 80% fewer smog-forming emissions and excellent fuel economy are "bad" because you have to recycle a battery 15 years down the road), or dangerous.
Here's a hint: don't compare a 3000lb 4-door large family vehicle (mid-size in the US) to a 2-door diesel subcompact. It makes you look stupid.
The first rule of fuel efficiency is: BRAKING IS FOR LOSERS.
Absolutely, and that's still important in vehicles with regenerative braking.
The Prius has a bar graph of your MPG per five minute interval. It overlays cute little green car icons to show how much energy you recaptured through braking during that interval as well. But you shouldn't think of those car icons as part of your score. They're more like the bonus you get when the ball drains out of the pinball machine.
Consider this: when you step on the brakes in a Prius, you convert kinetic energy to electrical energy, which is then stored in a battery, which you then use to regain kinetic energy.
But oddly enough, the most efficient way to store kinetic energy is as....kinetic energy. Regenerative braking is a consolation prize for when you had to step on the brakes. Better not to do that in the first place, if you can manage it while being safe and courteous.
And yes gasoline is so cheap for the most part that we can and do by bigger cars that do poor mpg. They sell gas at 25-30p a liter and 9p of that is road tax, so we don't have the extra payments like you do. At that price it just doesn't make much of a dent in the pocket book even when you have to commute more than 30 miles each direction everyday. The other thing we have is wide roads, lot's of parking, and big garages (you can actually get a full sized SUV into most and have the people on both sides of the vehicle and be able to get out fairly easy). The newer houses typically have room for 3 vehicles and easily fit 2 SUVs and a car. (Just to give you an idea of what I'm talking about, a Landrover Defender 110 station wagon is what I mean by an SUV.) Those things seems to have a bigger damper on large vehicle sales here in the UK than the price of gas. I cannot get my "tiny", a behemoth by British standards, regular cab Toyota Tacoma (like a hi-lux but bigger) through the door of my garage, and have to park it in the street. Of course as you know most houses in town don't even have garages. People in the states regularly drive pick-up trucks large enough to haul around the typical British car in the back and rarely ever have a problem finding an easy spot to park in.
Hope that puts things in perspective for you. Of course my dreams of buying a new Tacoma or an FJ cruiser, both larger than I have now, are on the back burner, so I have been eye-balling one of the new Mini's. (The sad thing is it won't fit in my garage either.) It get's a respectable 35-40 mpg better than the 20 I get with the Tacoma. Of course the one I want is the S model rather the eco model. :)
Some people have converted the Prius to a plug-in hybrid vehicle (PHEV) and there's at least one company doing the conversions commercially. It does not become 100% electric, but it does allow you to plug into a wall socket and charge up the battery, then drive some distance (maybe 40 miles) on the battery power before the gasoline engine ever fires up. If you don't drive more than 40 miles in a day -- which would cover most days for me -- then you don't use gasoline. Yet, if you need to take a long trip, you can do that too.
:)
Toyota have announced they want to build a PHEV, but they haven't said when or shown any more information about it. General Motors have shown the Chevy Volt "concept car" which is a PHEV, and they want to put it into production by about 2010-2012 depending on how batteries develop.
The winners in fuel efficiency are always the pure battery-electric vehicles like the Tesla Roadster; it's rated 135 MPG equivalent efficiency on the EPA highway cycle, no funky "hypermiling" techniques required. First deliveries to customers scheduled for late this year.
"Unfortunately at least in this country (UK) you are likely to cause a case of road rage. All driving schools teach a completely different driving style. Namely, you are taught to go close to the roundabout without deccelerating and switch 4-to-2nd or 5-to-3rd for the big ones to kill your speed right away with the engine while helping yourself with the breaks. Same for traffic lights, stopping, etc. Even if it is absolutely clear that a traffic light will go green any minute, the average british driver will go all the way to it, break, stop and wait. As a result if you deccelerate early the one bihind you may end up smashing into you or uses breaks to deccelerate early and gets pissed off."
Not sure I agree with this. I was taught to always change down one gear at a time. If you use engine braking by changing down TWO gears at a time, you're going to slow down fairly rapidly WITHOUT YOUR BRAKE LIGHTS COMING ON. This is much more likely to cause a) rear-end accidents; and b) road rage; than slowly down gently. I slow down the way the GP post described, and I never have any problems drivers behind getting annoyed (though I can see they might if you did it "to excess" (i.e. risked yourself and the cars behind not being able to get through the lights when they turn green)).
Yes.
I fqPO/890029.PDF. The "transmission" has only 6 gears in it (not speeds, gears), no mechanical torque converter. A diagram of it is on page 18 of the PDF file. The other gears are for connecting to the differential. Electronically it is complex, but not mechanically. The engine is a conventional 1.5L 4 cylinder engine, but run with the Atkinson cycle instead of the usual Otto cycle.
The drivetrain in the Prius is quite simple. See http://www.osti.gov/bridge/servlets/purl/890029-W
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I don't know where you live, but if you are in Vancouver, you might want to try the Co-operative Auto Network. It's a co-op where you pay a one-time $500 membership fee, and per hour fees (as low as $2/hr) to sign out various vehicles for short periods of time.
It's ideal for folks like you where you have a primary vehicle, but occasionally need a secondary. The co-op fleet has trucks and vans. My wife signed up, and it's better than purchasing (and insuring) a second car. Plus, she gets to satisfy her Mini Cooper fetish (the co-op has three that you can sign out) without having to shell out the bucks.
The Prius' CVT seems to be mechanically simpler than a conventional automatic transmission. AFAIK there are no clutch plates, no torque converter and only 1 planetary gearset. I took some pictures of FWD and RWD automatic transmissions and put them up at http://priuschat.com/index.php?showtopic=30245&st= 0&p=403617&#entry403617. You can look at what the Prius' CVT/PSD (power split device) look like a little further down and at http://privatenrg.com/#Planetary_Gear. http://eahart.com/prius/psd/ has some more info and a simulator.
A Prius doesn't have an alternator, the inverter works to charge the 12V aux/accessory battery. It doesn't have a starter either, MG1 acts as the starter.
Mother Jones published an article some weeks back about the "hypermilers," a number of automotive enthusiasts whose method of madness is getting as much gas mileage out of a car as possible.
Some of the techniques they use include avoiding use of breaks whenever possible, attempting to stay at 50mph a much as they can, taking turns at the fastest possible speed, and strategizing as they drive to hit traffic lights when they're green as often as possible.
In short, a very very Slashdot way to drive....
Per http://www.epa.gov/otaq/cert/mpg/fetrends/420s0600 3.htm, the average curb weight of 2006 model year vehicles sold in the US was 4142 lbs. 50% of them were "light trucks" which includes SUVs, minivans, pickups and some vans.
There are an insane # of solo and/or soccer mom driven 5000+ lb. SUVs such as Ford Expeditions, Chevy Suburbans, Yukons, Tahoes and Lincoln Navigators. Hummer H2s are even worse w/ 6400 lb. curb weight. They're exempt from even being TESTED for mileage and don't even count against GM's CAFE (Corporate Average Fuel Economy Numbers) per http://www.fueleconomy.gov/feg/which_tested.shtml because they have over 8500 lb. GVWR.
They're gross polluters and a danger to other drivers.