Another Stab At Sorting Hybrid Hype From Reality 633
Attila Dimedici writes "Eric Peters makes the case that hybrids have been over-hyped. His argument is that in order to sell people on hybrid cars, automakers have emphasized the energy efficiency of hybrids in ideal conditions and failed to tell people that in most ordinary driving conditions they will not come close to meeting the numbers given. He refers to a recent case where an individual has chosen to forego membership in a class action law suit and has instead chosen to go to small claims court. He suggests that there is a significant chance that she will win there and that this will open up all of the manufacturers of hybrid vehicles to similar lawsuits.
The article was on a rather partisan website, so I am curious what factors he has chosen to overemphasize to make his case. (Or what factors he has chosen to ignore to the same end.) I know that Slashdot has a large contingent of hybrid and EV supporters who are well educated on the subject (as well as a large contingent of those who are not so well educated)."
First Anecdote! (Score:3, Insightful)
My wife and I both have hybrid cars (a prius and an insight) and we both consistently get mileage in the mid 40s.
Re:First Anecdote! (Score:5, Insightful)
The big part is that a lot of the "savings" on a Hybrid assume you are driving it like a Hybrid should be.
Rather like all cars. They advertise a certain fuel efficiency, driven properly. Most people gun the accelerator off every stop, try to do 80 in a 55 zone down the freeway, and do other things that reduce their fuel efficiency. Meanwhile, you get people who do things like this [hypermiling.com] that can squeeze a lot more than the "normal" fuel efficiency out of even a standard vehicle.
The biggest thing with Hybrids is that they are designed to invert the normal efficiency ideas. Usually, you get a lot more efficiency driving a steady rate on the freeway. It's one reason they list dual "city/highway" mileage targets on the sales brochures. With a hybrid, that's not the case, because a lot of the efficiency gains have to do with recapturing energy from stop-and-start driving.
From TFS: "His argument is that in order to sell people on hybrid cars, automakers have emphasized the energy efficiency of hybrids in ideal conditions and failed to tell people that in most ordinary driving conditions they will not come close to meeting the numbers given."
We could easily rewrite as follows:
"His argument is that in order to sell people on compact cars, automakers have emphasized the energy efficiency of compacts in ideal conditions and failed to tell people that in most ordinary driving conditions they will not come close to meeting the numbers given."
TL:DR version: if you drive a Hybrid like a fucking sports car, you'll get sports car fuel efficiency. If you drive a Hybrid long distances on the highway, guess what, you'll get the raw gas mileage of the gas engine only minus whatever it's wasting on air conditioning and electrical generation.
Re:First Anecdote! (Score:5, Informative)
I disagree. Although the younger crowd might stomp on the gas at every light, the adult crowd tends to outgrow such things. I have two hybrids and one common gasoline engine and the hybrids normally average the expected gas mileage that was on the sticker. No idea where TFA gets the idea that the claims are vaporware when my household seems to have no problem attaining such figures. I live in a large metroplex so the bulk of my driving is city driving which also happens to be the ideal condition for a hybrid.
Perhaps the author didn't understand the environments where hybrids shine and the difference between that and simple highway driving?
Such efforts would do better to require that the EPA redefine the monroney sticker/MPG standards to be a bit more realistic. If the auto manufacturer's comply with the requirements for the posted ratings, I don't think this will go anywhere. They recently revamped them to better reflect the (then) today's driver. I want to say it was about 10 years ago, prior to the influx of hybrid and electric vehicles. Sounds like it's time for another review.
Re:First Anecdote! (Score:5, Insightful)
I think there's a tendency to stomp on the gas for anyone whose time value exceeds their gas cost. I can cut an average of over 5 minutes per day off my commute by stomping the gas. Call that 2 hours per month. Does it cost me an extra $240 / month in gas an maintenance? No.
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...I can cut an average of over 5 minutes per day off my commute by stomping the gas...
Wow...just, wow.
I take my dog for a walk on the beach, everyday, for an hour. If I walk faster, I can be home 5 minutes earlier.
Re:First Anecdote! (Score:5, Insightful)
If I'm home 5 minutes earlier, I can walk my dog for an hour and five minutes. Or play with my kid 5 minutes longer. My commute is not anywhere near my top 10 list of things to enjoy.
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...I can cut an average of over 5 minutes per day off my commute by stomping the gas...
Wow...just, wow.
I take my dog for a walk on the beach, everyday, for an hour. If I walk faster, I can be home 5 minutes earlier.
I wank my self off for ten minutes each day. If I do it faster I could come five minutes earlier
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Re:First Anecdote! (Score:4, Insightful)
Just how long is your commute and poorly timed are your traffic lights that you can cut 5 min/day from your commute by stomping the gas?
Unless on the freeway, I find that the majority of the time I catch up to the guy "stomping the gas" at the next light because he's had to stomp the brakes at the next red light.
And are you really finding that 5 minutes noticable?
Personally, I find that many people turn into arrogant, self-serving, aggressive douche-bags when behind the wheel of a 2-ton automobile. And they'll use any excuse to blame that behavior on something else when driving aggressively is clearly linked to increased accident risk. (and yes, scientific studies back this up)
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There's your first mistake again. Or rather, a mistake of how fucked up US city design is.
Re:Take what action? (Score:4, Insightful)
Crowd into sardine can high density housing alongside a rapid transit corridor, of course, like the overlord city planners intend. If you want to see a tree go to a fucking park on your day off and look at one. Above all, remember this: Obey!
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It is, in fact, the only other option available. Maybe another option is possible, but since it doesn't exist currently, it's not available.
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...we'd waste it on something else shiny.
Giving money to Congress is like giving whiskey and car keys to teenage boys. (To completely mangle a quote whose source I don't immediately recall.)
Weather effects (Score:4, Interesting)
Temperature has a huge effect on my 2005 Prius mileage. Below about 40 (F), the engine runs longer to warm up the catalytic converter--and even more if you want heat. Below about 20, the mileage gets worse--perhaps because I really want heat and leave the engine running while I clear the windshield.
Above 50F, I consistently exceed the rated mileage -- and even during the summer with the AC I get 48+ mpg.
There is certainly an effect of the big mileage meter on improving your driving habits.
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Sort of agree. If I baby my Escape Hybrid SUV, I get real world average (highway/city/country) of between 36 to 40mpg. If I drive like I always did, I get 32 to 35mpg. However this is about twice what I was getting in the non hybrid v6 I was driving before that with no change in perceived power or acceleration. So yes the mpg is overstated but so is the gas version. regardless the hybrid gets far better mileage in my experience and I'd get another without hesitation.
Re:First Anecdote! (Score:5, Informative)
The big part is that a lot of the "savings" on a Hybrid assume you are driving it like a Hybrid should be.
Bullshit. The problem is that the manufacturers have no say whatsoever in how those mileage ratings are derived. The tests are very precisely specified by the EPA, and the manufacturers are not allowed to deviate in any way, nor publish any mileage information other than the figures from those tests.
The manufacturers have actually been quite open that the current tests, designed long before hybrids existed, tend to overstate the mileage for hybrids even more than they overstate mileage for regular cars. However, the EPA has not revised the tests, and the manufacturers are stuck with the mileage ratings from the government-specified tests.
And this of course pretty much dooms these lawsuits...
Re:First Anecdote! (Score:4, Informative)
Re:First Anecdote! (Score:5, Interesting)
The only way your GTI gets 31 mpg is if the stoplight in question is at the top of the mountain and you coast the rest of the way down. Sheesh! You're not going by what you see while cruising on the highway up on the trip computer, right? (BTW, 'trip computers' are notoriously bad from what I've seen. If you go to forums for a particular car and look at what the trip computer folks are reporting, vs. the people who really measure, you can often see a 5-10 mpg difference, with the trip computer almost always reading high.) GTI's typically run in the 16-22 mpg range, depending on how driven and type of driving from what I've seen.
You're correct however, about the TDIs. Our Jetta TDI has averaged 34.58 mpg over about the last 1.5 years in mostly city driving (measured by filling the tank at the same station and pump most of the time, and recording the amount of fuel and distance traveled each time... not quite as accurate as some methods, but much better than the trip computer.... and over that long of time, it starts to become pretty accurate.) We've never really taken a true highway trip. The closest we came is a trip through the mountains where we got 41 mpg for a tank. I know the TDIs are capable of much better in true highway situations.
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So if you accelerate fast (not till you spin your tyres), but don't brake unnecessarily or go way over speed limits (thus increasing wind resistance losses), you shouldn't be lowering your mpg that much.
Re:First Anecdote! (Score:5, Funny)
I have ADD and drive my manual transmission just fine, you insensitive clod!
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Continuously Variable Transmissions haven't come close to automotive implementation yet
Really? The Mercedes A-class I drove a little while ago had a CVT that seemed to be pretty well implemented, and you might check the list on Wikipedia [wikipedia.org], starting in 1923 and including more than a dozen in the last decade or so. Even some American models.
Re:First Anecdote! (Score:5, Informative)
The one in a Prius does very well. The old style belt and variable pulleys are not what I consider long life. The planetary gear set in a Prius with the pair of motor generators to implement a CVT has reduced the weight and complexity of a transmission to the point where all friction components (clutches, bands brakes) are eliminated along with all hydraulics. All mechanical shifting is gone. It has no clutches or gears that engage or disengage. This is true from freeway speeds forward to reverse. The only mechanical part that is shifted is the park cog.
I have over 160K miles on mine. At 100K I changed plugs. Other than that, it has needed only normal oil changes and such. With regenerative braking, it is still on it's original brakes. For a zero breakdown car with no mechanical issues, I have no complaints. The milage is less then the EPA estimate, but it is way ahead of any other car I owned. My lifetime average MPG is 45.3.
I have no reason to sue the manufacture for this. All cars by all manufactures did not do as well as the EPA estimates in 2002. Hybrids are no exception.
Never changing any belts, alternators, water pumps, brakes bulbs, etc in a decade of commuting is a great trade off. I have had to change the small 12 volt battery a couple of times, ~5 year intervals, and tires about every 60K is not a problem.
The gas savings over my old car with 160K of driving is considerable. The cost savings in maintenance is a bonus. Not meeting EPA guidelines on MPG, not a surprise for city traffic. Stoplights and traffic kills millage. I'm impressed it does as well as it does.
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That pretty much matches my experience with my Prius. The mechanic at the Toyota dealership told me that they still haven't had to replace the brake pads on any Prius (and this is at a large dealership in Boulder, CO that sees tons of Prius cars).
I also average about 45-46 mpg overall. I don't deal with too much congestion, but drive over big hills every day. The cold weather also hurts mileage.
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Same experience with our Hybrid Camry. Oil change and tire rotation every 5K miles, and we just rolled over 90K miles. Original brake pads are still on the car, although we did have to replace the water pump due to a leak about 5K miles ago. Very satisfied, although our next vehicle is a Tesla Model S.
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"I have had to change the small 12 volt battery a couple of times, ~5 year intervals, and tires about every 60K is not a problem."
I went to a computer controlled battery charger that can keep it trickle charged when its not fully charged and off when it is. Consequently, I've totally eliminated the two or three episodes where I didn't drive the car frequently enough to keep the battery charged (I travel for months at a time abroad or cross country). The charger I picked up from my Toyota dealer has been w
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The milage is less then the EPA estimate, but it is way ahead of any other car I owned. My lifetime average MPG is 45.3.
The updated EPA numbers (which are supposed to be more realistic) for the 2004-2009 Prius is 46 mpg. I would hardly consider 0.7 mpg (or 1.5%) significant.
FWIW - my 2008 Prius gets similar fuel economy - 45-46 mpg on average as measured from the gas pump and odometer readings.
Interesting, I typically do slightly better than EPA on the highway rating of 45 mpg unless there is a strong head or cross wind or pushing speeds over 75 mph. Typically pure city driving is worse than the EPA rating of 48 mpg where
Re:First Anecdote! (Score:4, Insightful)
That was your first mistake
0) Your mistake is assuming/implying when I say "I don't think" it means I'm not thinking. Read the rest of my post including the second line, AND the rest of the thread I'm replying to for context. I was claiming that there's not going to be a big difference in MPG between slow and fast acceleration, despite common assumptions about "jack-rabbit" starts.
1) I said modern, so the transmission slippage loss is about 5% not 10%. And nowadays there's these new fangled things you may not have heard of, called lock-up clutches: http://www.autoshop101.com/forms/AT02.pdf [autoshop101.com]
to prevent this, and to reduce fuel consumption, the lockâ'up clutch mechanically connects the impeller and the turbine when the vehicle speed is about 37 mph
Below that speed you get the "slippage" loss whether you're accelerating slow or fast. If it's 4% (slow) vs 5% (fast) it's not going to make a big difference to your MPG, which was my point (hard acceleration vs slow).
2) For modern engines whether you accelerate fast or slow doesn't make a big difference to the efficiency of the engine, unless you're red-lining them. In fact the maximum engine efficiency for many cars is not between 1000-2000rpm, but higher - even 4000+rpm for some cars (Ford Focus). The OP's car is a turbocharged GTI, I won't be surprised if it's more efficient at higher RPMs. For such cars if you accelerate very slowly, you'd be operating the engine at the lower efficiency band for a longer time, so it's not going to be so much more efficient than accelerating hard even if accelerating hard means staying in 2nd gear for longer. Hence it's not going to make a big difference to your MPG, which was my point.
3) About 30 years ago[1] apparently BMW did some research where they found that brisk acceleration was more efficient than slow acceleration. Some hypermilers claim this still applies.
[1] http://goo.gl/7kwJd [goo.gl]
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For modern engines whether you accelerate fast or slow doesn't make a big difference to the efficiency of the engine,
Perhaps true for the modern turbo-charged cars, but any naturally aspirated petrol car is most efficient when it is at the highest load. This means pretty much pedal to the metal but in as high a gear as possible. This is not true if the engine control makes the mixture less lean in that situation, but it seems most engine controls only do that at higher RPM's (which is another good reason to avoid high RPM's)
Petrol engines really suck at partial load. You really want turbo so you can get away with a tiny e
Incorrect information on CVTs (Score:5, Informative)
CVTs have not only been implemented on a number of popular cars, they are almost ubiquitous in some applications.
- Many of the Hybrids on the market either come standard with a CVT, or have it available as an option.
- Virtually every modern Scooter on the market is equipped with a CVT.
- Several motorcycles are available with a CVT (Aprilia Mana comes to mind,) although it hasn't caught on for marketing reasons.
- Several full sized cars are available with a CVT, or come equipped with one standard (Nissan Murano being the best known.)
Renault actually built and tested a CVT Formula 1 car, the FW15C, however it was banned before it ever saw competition.
http://www.f1fanatic.co.uk/2007/05/03/banned-continuously-variable-transmission-cvt/ [f1fanatic.co.uk]
http://www.f1technical.net/forum/viewtopic.php?f=3&t=3966 [f1technical.net]
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Continuously Variable Transmissions haven't come close to automotive implementation yet
I believe the most hybrids, including the Prius, use a continuously variable transmission. They always have. I've driven one.
Re:First Anecdote! (Score:5, Informative)
Sheesh. So much garbage in one post.
So, I drive a Toyota Prius. It does get that good gas mileage advertised on the sticker. Yes, I do floor it from time to time. Yeah, some of the time I drive like I'm carrying eggs to the Czar, but I did that with the car I had before this one, too. Mostly, I just DRIVE THE CAR.
In no particular order:
1. The Prius does implement a CVT. It's electric, not with belts, and it doesn't slip. Power in vs. power out is no better or worse than a standard automatic, or maybe even a manual. Advantage: It allows the engine to spin at its most efficient spot for the power required.
2. The Prius's engine isn't, technically, an Otto cycle engine. It's Atkinson. Atkinson's have better fuel efficiency than an Otto, but they got lousy torque. Oh - look at that: There's a couple of electric motors in the drive train! These>do have torque, and lots of it. So, maybe this car doesn't leave rubber strips behind it when it gets floored. On the other hand, neither did my old Civic. Or the VW I had back in the day. On the straight and level this engine pulls 55 mpg at 65 mph, better at slower, worse at faster.
3. So, up and down? The engine on the 2010+ Prius has about the same horsepower as any car its size, so there's no trouble climbing hills. Yep, you do get less gas mileage when doing so. But, when you're going downhill, the Prius isn't shy about cutting off the fuel to the engine and dumping some energy into the battery. Yep, you only get some 30% of the energy back after taking all the losses in the electronics into account - but that's better than the 0% with a conventional car.
4. Braking. After the round trip through the batteries/electronics you get 30% of the energy from the stop. That's still better than the 0% that a conventional car gets.
In general, hybrid cars are just getting started. A good deal of the losses in a hybrid have to do with the silicon MOSFET transistors in the inverters that take energy out of/put energy back into/ the electric motors on a hybrid. In the near term silicon carbide transistors are coming. They have less RDSon (less resistance), switch faster, and can tolerate much higher temperatures than silicon. So, there's better electrical efficiency right off, hence cooling requirements are less, and, with the higher temperature tolerance, the transistors don't have to kept as cool. Therefore, the energy required to move all that cooling fluid around the inverters gets reduced by large double-digit percentages and the weight of the additional cooling gear also goes away. 70 mpg, anyone?
If you want to point fingers at idiots, then point them at the engineers and marketing people at other car manufacturers who, when faced with the Prius, built cars with stupid little electric motors bolted in the same place where one would put a starter motor, rigged said motor to give a bit of a power boost on acceleration, resulting in "Not Much Change", then had the gall to call such cars "hybrids". Even when the blame things got worse gas mileage than their non "hybrid" brethren.
If you want to have real fun, think about the gas mileage on a Toyota-style hybrid diesel. 90 mpg, anyone?
Remember: It's not just the more efficient Atkinson engine and battery combination. It's the energy recovery and the ability to go medium to short distances on battery alone with the engine off. The Prius really was a break-through. Everybody else is just playing catch-up.
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Thank you for that. The reality is, drivers of cars nowadays generally do get the advertised mileage. This wasn't true before the EPA standards were revised, but it is now. For example, concerning the Prius, compare the rated mileage with the average of real-world reports [fueleconomy.gov]. Punch in any car you want there -- you'll find a surprisingly good correspondence.
And contrary what people have been saying elsewhere in this thread, hybrids are *not* only about "energy recapture". The energy recapture isn't even th
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Actually the losses in the inverter are fairly low. I read some papers describing the efficiency of the inverter design being over 90% efficient. One interesting paper I found can be found at http://www.midmichigansae.org/documents/DrGoverPresentationSAEApril20.pdf [midmichigansae.org]
Re:First Anecdote! (Score:5, Informative)
Your mistake is you haven't read anything about automotive technology since 1985.
CVTs are in tons of cars, granted smaller ones. The Suburu Justy had one way back in the 90s, and they're coming in larger cars now.
Finally, drivetrains are much more efficient than they used to be, thanks to the lock-up torque converter that another poster mentioned, better shifting algorithms and transmission control computers, but more importantly the DSG transmission that tons of VWs and Audis (and a few Fords) now come with. They have consistently better efficiency than manuals. If you don't know what a DSG is, I suggest you consult Wikipedia and catch up on technological developments over the last quarter-century you've apparently missed out on.
Of course, since you used the term "standard transmission", that shows that you're probably over 65 years old as that term hasn't been used in decades, so maybe that's why you're so out-of-date.
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Yes, he is. To get a mass of car from zero to some new velocity needs an amount of energy, which needs a set amount of fuel. Even assuming perfect efficiency, zero friction, and everything as optimal as physics allows, there is still an upper limit on fuel efficiency which can only by subverted through the use of regenerative breaking. Cars have gotten closer, but right now they are about as efficient as they are going to get
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Yes and larger vehicles are more likely to either strike something or be struck by something by virtue of their larger size. The media and the SUV manufactures like to over-accentuate dramatic crashes to hype the safety statistics, which look only at instances where there was a crash and not the far more frequent episodes when a crash due to being in a smaller car was avoided.
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Re:First Anecdote! (Score:4, Informative)
To some extent, gasoline engines are designed for maximum efficiency and clean burning (slightly fuel lean) at below maximum throttle. At maximum throttle, the engine gets extra fuel to ensure that all the air that can enter gets burned. That lowers efficiency.
There are other factors that reduce efficiency at full throttle: more tire slip, more slip in automatic transmission's torque converter, and pumping losses in the crankcase and alternator (and anyplace else that there's a fluid) which are proportional to the square of (rotational) speed.
Although it seems counter-intuitive, obstructions like the throttle plate don't really substantially affect efficiency beyond what the Carnot law demands.
Re:First Anecdote! (Score:5, Insightful)
When any car company relies on "EPA Testing" to make it's mileage claims, they are based on the same unrealistic driving conditions and restrictions as the hybrid manufacturers.
Car manufacturers are REQUIRED to use the EPA numbers. It's ILLEGAL to use anything else. So why are the car manufacturers being sued again?
Re:First Anecdote! (Score:4, Interesting)
Which if you think about it is pretty pathetic. Diesel cars have been able to get that for years. There are definitely places like Minnesota where diesel is a lot less realistic, but hybrids aren't going to make much sense there either as batteries don't like the cold any more than diesel does.
Re:First Anecdote! (Score:4, Insightful)
Mid 40's is nothing new. Honda CRX's were doing it in the 80's. In the mid 70's the Mercedes 300d's were getting upper 30's with ac on, on the highway. In the mid to late 80's their SD's were doing the same with a lot more power. Many, many of those cars are still in service to this day with 100's of thousands of miles experience. Many even running bio.
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Re:First Anecdote! (Score:5, Interesting)
Which if you think about it is pretty pathetic. Diesel cars have been able to get that for years. There are definitely places like Minnesota where diesel is a lot less realistic, but hybrids aren't going to make much sense there either as batteries don't like the cold any more than diesel does.
Agreed, mid-40s in miles per US gallon is pathetic indeed. I drive a diesel Mercedes C stationwagon (similar in size to the Prius V), and average at least 55mpg (US gallons) in our usual mix of driving, which encompasses comparable distances of highway, rural dirt road, suburban, and urban driving. In summer it usually gets better than 60mpg, mostly because the road conditions are less likely to be nasty. The car is almost 9 years old, and has about 320000km on the clock.
Incidentally, I live in central Finland, which has winters not dissimilar to those of Minnesota (been there, in summer and winter and in the transitions between them). Relatively modern diesel cars are quite OK in such climates; the filling stations change the diesel mix for winter to account for the cold.
Re:First Anecdote! (Score:4, Informative)
the filling stations change the diesel mix for winter to account for the cold.
This actually goes on everywhere in the world, not just places with a cold winter. A 10degree shift in temperature is enough to allow a change in blends of diesel and gasoline which allow crude oils to be processed in more efficient ways.
Even in places really hot like northern Australia during the summer where it's 45degC and in winter when it's 25degC the standards allow oil companies to change the Residual Vapour Pressure and do things like put more butane (cheap and difficult to sell product) into the petrol. In the summer this would cause high pressure in petrol tanks and the butane either needs to be sold or processed into something else.
Re:First Anecdote! (Score:4, Insightful)
And no less realistic than the Nordic States or high altitude location in Europe. Modern diesels run just fine in the winter and start jut fine too. Will my fellow Americans quit spewing rhetoric from the 70s?
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I have had a Prius for a number of year now. I get mileage of between 45-48 mpg and have used it extensively not only for local travel, but medium and long distance (cross the US travel). The trick is to learn how and when to accelerate so that you can maximize the thrust produced by the electric motor. I've heard of experienced drivers getting up to 80 mpg, but I think that requires special tires.
The best part on a long trip is pulling up to a gas station and rarely having to pay more than $20 to get
Not only hybrids (Score:5, Interesting)
Also not their decision (Score:5, Informative)
The EPA defines how energy efficiency numbers are calculated, and those numbers have to be displayed on the car. The car companies could advertise a lower number, but there is no simple one number that tells the whole story, and you can't give a full technical report in a 30 ad. By all using the same system to determine the fuel efficiency at least the numbers are relatively meaningful even if the absolute value isn't directly true for all circumstances.
Finally, good luck suing a company for false advertising when the numbers they are using are determined by government testing, not by the company.
Honda's bait and switch (Score:5, Interesting)
Disclaimer: I own a 2007 Honda Civic hybrid.
The complaint about the Civic hybrid is that the car was sold as achieving 48/51 mpg according to EPA estimates.
With normal driving (normal = the type of driving seen every day, exhibited by most drivers), it was not possible to get much closer than 10 mpg of those figures when the car was purchased.
Now, this hybrid has a power assist design (different to the Prius), which lends itself to easily draining the battery - climbing a hill, for example - and the battery only has a limited number of power/drain cycles before it needs replacing.
It turns out that the programming on these cars was initially set to provide more 'assist' - thus improving the published mpg figures - but that has led to premature failures of the battery, leading to many warranty replacements.
Honda's response to this design dilemma? Change the programming so that the power assist is much more frugal. This reduces the cycles on the battery which makes them last longer, but means that the car now averages about 30mpg, since you have less assist from the battery when you need it.
So now, instead of having a car that is somewhat better than the non-hybrid counterpart, it is about the same at best, and has few or none of the attractive attributes that Honda used to sell the car.
We are upset at being conned by Honda selling the car as a high-performing hybrid, and later effectively remove most of the benefits of the hybrid because their design doesn't work.
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My 2004 Prius still gets close to the EPA estimate (Score:5, Informative)
I have a 2004 Prius with almost 200,000 miles on it. I have a 70 mile per day commute, 60 freeway/10 city, in Southern California. I drive at normal freeway speeds (for California), and had the carpool sticker which was discontinued last July. In the carpool lane, I was able to average between 75 and 80MPH during my commute, which has a few hills, but nothing major (I-405 South from 55 to San Juan Capistrano and back).
I have been averaging about 48MPG on this commute since the day that I got the car.
I am by no means a hypermiler, but when my wife drives the car, she is lucky to get 40MPG in the city, since she has more of a lead foot than I do. On a long freeway trip at 80MPH, she can get about 45MPG. I can get a higher mileage if I drive slower (65MPH or below). In that case it goes above 50MPG. If I get caught in traffic on the freeway, the mileage improves (during stop and go traffic).
My previous car was a Plymouth Neon that got 24MPG, so my MPG has been doubled for the last ~200K miles. According to my rough calculations, at that mileage, I purchased about 4166 gallons of gasoline since February of 2004. If you figure an average price of $3 per gallon (which is really not that far off for Southern California since 2004), that is $12,500. If I was able to keep my old car (which was going to require extensive/expensive repairs in order to continue operation), I would have paid $12,500 more for gasoline over that same time period. So therefore, I have saved $12,500 so far. The premium that I paid for the Hybrid system was less than that, so it has more than paid for itself. I ordered a Prius with none of the extra options except the side-curtain airbags which are now standard, so I paid quite a bit less than the fully loaded Priuses that they were selling at the time.
Hopefully my next car can be a pure electric, if I can make my Prius last that long. Maybe a plug-in Prius or Chevy Volt would be a reasonable alternative. That carpool sticker saved me thousands of hours of time as well (over the years). I really miss it!
Re:My 2004 Prius still gets close to the EPA estim (Score:5, Insightful)
People conveniently forget the air-quality benefits of hybrids. There's a huge lifetime difference that can be quantified in health improvement (healthcare cost reductions), lifestyle improvement, etc.
It's not all about the MPG.
Re:My 2004 Prius still gets close to the EPA estim (Score:5, Insightful)
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In theory, because hybrids use a gas engine that runs at a constant speed, it's more efficient and pollutes less.
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While emissions and amount of fuel burned are correlated, they're not fixed ratios. For example, if not all the fuel is burned, there will be less CO2 and more hydrocarbons in the emissions. And if it uses a lean mixture to make sure that all the fuel gets burned, that increases the NOx emissions. Running in the engine's most efficient band makes it run hotter, also increasing NOx - but exhaust gas recirculation is used on many engines to dilute the fuel/air mixture with something that doesn't burn, cooling
the article seems a bit muddled (Score:5, Informative)
Hybrids are probably overhyped, but I thought most educated consumers these days realized that they got the biggest efficiency gains in two types of driving: 1) lower-speed, stop-and-go city traffic, where they can mainly use the electric drivetrain, and sometimes turn off the engine entirely for brief periods; and 2) constant-speed highway travel, where they mainly use the gas engine, but one that can be made smaller due to being able to rely on the electric assist when needed. Yes, if you frequently accelerate at higher speeds, you'll use both the electric and gas engines and not save much. Do people not know this?
I never get to see "100MPG+" (Score:3)
I am always disappointed that the real-time display in every car I have seen tops out "99.9". I know it is not meaningful, but it would be fun to see on more digit.
But on a practical note, having one of those computer displays can be motivating, in modifying your driving style, if one cares about mileage.
Re:the article seems a bit muddled (Score:5, Insightful)
Uh, yeah. But you can get the same in a non-hybrid coasting down as well...
But a conventional car doesn't regenerate gas in the tank on downhills to help you get over the next hill, while a hybrid will recharge the battery.
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Precisely, the type of driving you're doing makes a huge impact on the results you get from driving a hybrid. Hybrids are really great in heavy traffic as they'll power down and go electric when you're in stop and go traffic. Regenerating some of the energy lost to braking and not having the engine idling when one is just stopped.
Around here most of our buses are hybrids at this point in one form or another.
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In an electric going downhill you shouldn't be using any fuel of any sort. Most gas engines will still need to burn some fuel to idle the engine if you're coasting. You aren't burning much fuel, but so long as the engine is still running you're burning some.
In most modern cars, the ECU will use deceleration fuel cut off (DFCO) to cut off fuel to the engine when it's being driven by the drive wheels.
Re:the article seems a bit muddled (Score:4)
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I've noticed that hybrids are popular as cabs in many cities. The drivers I've talked to all seem to really like them for driving and low operating cost. I think they do really well in city driving.
Listen to the users before bashing (Score:4, Insightful)
Re:Listen to the users before bashing (Score:5, Interesting)
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I love our Prius, but the savings on fuel probably won't pay for the added cost of the hybrid powertrain within the car's lifetime.
A plug-in hybrid charged at non-peak rates or on-site solar could be a different story.
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A lot of articles talk about the "payback" of hybrid cars and often conclude that "It's not worth it". I don't buy that. I never see articles on the payback of getting leather seats or a bigger engine that improves acceleration. The fact that my Prius emits many tons less of CO2 into the atmosphere than most other cars gives me more satisfaction than do leather seats (which I also have).
Many people choose to buy a hybrid mainly or solely based on the higher mileage ratings and therefore the savings in fuel costs. Assuming that maintenance costs are otherwise the same (which they may or may not actually be, according to other comments here), the hybrid has a higher initial price plus battery replacement costs. If your fuel savings over the life of the car are less than the additional costs due of the hybrid drivetrain, then it doesn't make financial sense to buy it. Depending on your exa
Re:Listen to the users before bashing (Score:4, Informative)
Exactly!
I can only speak for Prius since its the only hybrid I've owned, but the fuel economy has never been an issue. Battery life is well over 150,000 miles ( by other users notes ) also. Adding in the fact that belts are nearly extinct on the 2011 model engine and it's beautiful. This articles BS.
The lack of timing a timing belt is a big win and almost makes up for the cost of a battery pack.
On my conventionally powered car, I just had the timing belt (and water pump and a few other associated parts) replaced for $1600 (at 105K miles). The Prius has a timing chain instead of a belt.
My neighbor has 120K miles on his 2002 Prius and the battery is still fine.
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FYI many "conventional" cars have timing chains instead of belts.
That's true, but my point was that a $2000 battery replacement (after 100K miles? 150K miles? 200K miles?) is used a proof that hybrids are not economical, but many people accept a nearly $2000 required maintenance item on non-hybrids without question.
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Hype in Advertising (Score:4, Interesting)
in order to sell people on [x], [advertisers] have emphasized the [benefits] of [x] in ideal conditions and failed to tell people that in most ordinary [usage] they will not come close to meeting the [benefits advertised].
Sounds like advertising industry best practices to me.
We bought a Prius six years ago so my wife could use the carpool lanes for an hour-long commute through Los Angeles. We didn't get the EPA's mileage, but it's still double the mileage of our other car.
Re:Hype in Advertising (Score:4, Informative)
they use Imperial gallons
WRONG. we use liters.
EPA? (Score:5, Interesting)
Since the EPA does the testing and approves the mileage figures, doesn't this shield the manufacturers from liability for inflated numbers? The EPA sets the testing criteria. I know that I never hit the estimated city mileage for my conventional car and never expected to, so I only use the published gas mileage numbers to see relative mileage between cars. I never thought I'd hit that number exactly.
That said, the Prius owners I know are quite happy with their 40mpg+ mileage and are close or even over the published mileage. Granted, it takes a difference in driving style to hit that number (for example, by maximizing regenerative braking), but most people that buy a Prius are willing to help it maximize their mileage.
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I think the point is that Honda reprogrammed the energy management system to save the batteries at the cost of fuel economy; the reconfigured Hondas are fundamentally different from what they were when the fuel economy estimates were made.
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"Since the EPA does the testing and approves the mileage figures, doesn't this shield the manufacturers from liability for inflated numbers?"
And that is exactly what is wrong with government intervention in the marketplace, beyond contract enforcement and truth in advertising. The lying auto manufacturers can simply point to the government and say, "It's there numbers, not ours. We're indemnified." It would be better for consumers if auto manufacturers, or third party testers, published their own numbers. True, this wouldn't server the lowest common denominator of our society as well as government publishing the numbers. But, then again, maybe the lowest common denominator would creep upward because of that.
And you think that if the manufacturers could set the testing criteria that the numbers would be any more fair? At least with EPA numbers, all manufacturers have to follow the same standards. If the manufacturers did it, they'd all use their own methodology and you wouldn't be able to compare numbers between manufacturers.
If they used a third-party, each manufacturer would use the third party that gave them the best numbers.
I can counter his example with my own (Score:5, Informative)
I bought a 2011 Prius IV, and it works exactly as advertised. I drive about 15 minutes each way to work, about half highway and half road, and I get about 49 MPG, which is exactly what was advertised. The idea that you have to stay below 50MPH and never accelerate or go up hills is just silly (I live in Cincinnati, OH, which is fairly hilly as well). I have learned to not slam on the gas when I am taking off, but that is because it shows you your efficiency real time, so it's easy to see what you are doing to your mileage when you take of like a race car. Generally, I drive it like any other car, although the information it gives me allows me to drive a little better than I did in the past.
And I'm sorry, but no car will get the advertised gas mileage if you are going up mountains. This has nothing to do with hybrids and everything to do with that fact they don't take into account extreme driving conditions when they calculate mileage. This is actually the first car I have ever owned that gave me the gas mileage it advertised.
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"I have learned to not slam on the gas when I am taking off"
Let me ask you a question. Do you find sometimes yourself in the situation in traffic, where there are cars behind you and no cars in front of you, or the distance between you and the car in front of you ten times more than the distance between your car and the car behind you
The author is almost certainly lying (Score:5, Insightful)
The article author claims, "To get a steady 40 MPG (let alone 50 MPG) out of any hybrid -- and I have driven all of them, extensively -- you must keep your speed under 50 MPH and treat the accelerator as if it were a Fabergé egg."
I happen to own a 2003 Honda Civic Hybrid, and the _very first time_ I drove it on the freeway at moderately consistent speeds at 60-65 MPH, I got over 40 mpg. I still do that routinely.
So, either he's lying that he has "driven all of them, extensively", or he's lying about what you need to do to get that mpg rating. Probably the former--it's easy to drive a few in a not-very-MPG-friendly way, get disgusted, and then overgeneralize. Easy, but not terribly forgivable for a journalist.
A good case for not mixing science and politics (Score:4, Insightful)
This is a good case for not mixing science and politics. There are certainly cases where hybrids function better (inner city, garbage trucks, buses etc). These work well because the type of driving for these scenarios is ideal for regenerative braking. This makes for a best case scenario for allowing the hybrid to recover energy and work at it's peak. These cases justify the environmental price of the hybrid because the environmental costs is offset by their use.
When you consider the environmental cost that a hybrid requires (the Prius is well documented on the Internet for what is required for it's battery packs) if your not using a hybrid in the right conditions you are arguably harming the environment. This is because you are exacting an environmental cost that is not repaid through your usage scenario.
My point is most consumers are better off getting a high efficiency gas or diesel engine car (Cruze, Jetta etc). Most consumers do not have a driving scenario that is ideal for a hybrid car. It has been decades since most people lived in core cities instead of suburbs or the country. The bottom line is that different technology is better suited for different drivers. One is not fundamentally better than the other in all cases.
People are letting politics try to dictate science, when science should always be free of politics and allowed to stand on it's own merits.
Look at electric/gas horsepower (Score:5, Insightful)
The problem is all people are asking is, "is it a hybrid?" The question they should be asking is, "How hybrid is it?"
Honda Civic Hybrid '06
Gas engine: 85 hp
Electric motor: 13 hp
Saturn Vue Hybrid '07
Gas engine: 170 hp
Electric motor: 15 hp
Toyota Prius '07
Gas engine: 76 hp
Electric motor: 67 hp
There are plenty of cars that were technically hybrids, but when I bought a hybrid in 2009, the Prius was the *only* one which got a significant amount of power from its electric system. The rest were basically just gasoline engines with a little toy electric motor duct taped to them. The '09 Civic Hybrid I tested was particularly bad: larger gas engine than a Prius, 1/4 as much electric power, so it gets worse mileage, and with so little horsepower you feel like you're putting your life on the line every time you take an on-ramp.
Look beyond the hybrid label, and check out the size of the electric power system. It matters.
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It's about fiat currency, its about the need to drive the economy, the constant need to push ever-greater amounts of money into circulation to offset the spiraling inflation caused. The need to make everything more
I smell bullshit (Score:5, Informative)
We own a 8 year old Prius, we get slightly over 40 MPG, something the author claims is difficult. When the car was newer, we got over 42 MPG.
To get a steady 40 MPG (let alone 50 MPG) out of any hybrid -- and I have driven all of them, extensively -- you must keep your speed under 50 MPH and treat the accelerator as if it were a Fabergé egg.
We drive on freeways like everyone else, routinely driving 70-80 MPH. I'm not a lead-foot accelerator, but I drive like most people. I don't practice any exotic hyper-miling techniques.
There are also hills. Hybrids work best on a perfectly horizontal plane.
We also happen to live at the top of a large, steep hill (Berkeley Hills), which we go up and down every day. And yet we still get 40+ MPG, unpossible! The hybrid engine is great for recapturing some of the potential energy that would otherwise be lost.
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If other hybrids can't do this, then they are just fake hybrids that have just enough electrical hardware to get the label, but not enough to do anything useful. Or, they have 300-400hp and are not design
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The Prius is probably the only Hybrid where the reality of what a Hybrid MIGHT be meets the pavement. It's got engines that are roughly equal in capability, horsepower-wise, and similar thinking about it. The only negatives for the Prius is that the batteries are a problem that offsets IT'S gains on being "green". Most of the other Hybrids are as the author claims things right at the moment. And a wall-plug model of the Prius is actually MORE polluting than the gasoline only model- you cause more pollut
My non-hybrid VW Diesel has the same mileage... (Score:3)
Okay, I just got a major WTF. I wanted to know how my car compares to all those super-eco-friendly hybrids you people are talking about, and entered into Google "45 miles per gallon in liters per 100 km".
So, you see, my 2007 VW Touran http://en.wikipedia.org/wiki/Touran [wikipedia.org], being arguably bigger and more comfortable than a Prius, does a constant 39 MPG with its 1.9 TDI engine when I don't care about mileage. When I make longer trips or try to save some fuel (because it's much more expensive over here in German
Objectivity (Score:5, Insightful)
The Slashdot community is for the most part logically and scientifically oriented. We believe in the scientific method, and an understanding of the universe built on an accumulation of experiments built on logical and testable explanations for empirical data, observable phenomena and so forth. And in many fields of endeavor, there can be general agreement about things. For example, it's accepted almost by consensus that the nearest know star is the Sun, and that the next nearest known stars are the three in the Alpha Centauri system. Aside from a handful of cranks like Gene "Time Cube" Ray, virtually everyone accepts this. If somehow we found a star nearer than the Centauri ones, which was too faint to notice before, or right next to a much brighter star and unnoticed or whatnot, if the measurements were good and clear enough, I'm sure soon again everyone would be in agreement that this new star was the next closest one to the earth. It is far away, affects little here, and there's no reason for people to argue over it.
On the other hand, ExxonMobil is the most profitable company in the country. It made $30 billion in profits last year, off of $354 billion in revenues. It is #2 on the Fortune 500 after Wal-Mart (which had more revenues, but about half the profits in 2011). Chevron and ConocoPhillips are #3 and #4 on the list.
If hybrid cars were effective, that would dent the revenues of these three companies whose revenues were collectively three quarters of a trillion dollars. Does anyone think that this fact might possibly, conceivably hurt the objectivity of an article, released in a very partisan political magazine like the American Spectator?
Honestly, it doesn't even warrant attention, other than debunking. These types of articles belong in actually objective magazines like Consumer Reports or something, which could tell you which hybrids were good or weren't. Just from anecdotal evidence, people I know with hybrids have been telling me they are spending less at the pump. Which is exactly what worries magazines like American Spectator, which work to protect monopoly capitalism over actual economic growth in capitalism. We see these forces at battle all the time - the RIAA and MPAA want to go from a world where friends lent records to one another to one where that is impossible. The oil companies want us stuck on oil reserves until they run out and junky old gas-burning cars - and this also hurts industry, which would be helped by cheaper energy. AT&T and Verizon are more concerned with preserving their monopolies than having a growing wired and wireless network. Karl Marx said capitalism starts out as a progressive force, economically and socially, but eventually tends to get more and more mucked up in defensively protecting trusts and monopoly instead of smashing shibboleths to allow growth and scientific advancement. I'd say there's plenty of evidence around nowadays that he was right about that.
Well duh. (Score:5, Informative)
From the above, it's pretty clear that hybrid drivetrains are just a piece of the fuel-efficiency puzzle -- yet ever since those first two cars hit the market, manufacturers have been tacking electric motors to otherwise ordinary cars and selling them to gullible consumers as the saviors of Earth. The electric motors are a little more efficient at low speeds, but everywhere else they're just additional dead weight that the gas engine has to drag around. Is it any surprise that these half-baked hybrids don't perform as advertised?
Well .. it depends. (Score:4, Interesting)
There's certainly hype, possibly too much, but the devil is in the details here.
Gasoline-based internal combustion engines get a theoretical maximum 30% efficiency in converting the heat of burning the fuel into work. (This is the major reason why the conventional direct-drive internal-combustion engine configuration requires a radiator -- that lost 70% is being dumped out of the car as waste heat, minus the small fraction that's used to heat the interior of the car in the winter.) Non-hybrid configurations also have to size the engine for the maximum power output it's expected to have to handle -- usually accelerating to highway speeds -- and there are numerous compromises in the engine design that make it able to rapidly change power output across a wide range of power demands, all of which make it somewhat less efficient to operate in the more or less steady-state output it's called on to deliver for highway cruising.
Generally, that engine sized for peak demand during highway acceleration and tuned to be able to go from idle to maximum power and then back down to cruising throttle power over very short time spans is going to be less than the theoretical 30% Otto-cycle efficiency most places in the power band. (And chances are it's tuned to deliver maximum efficiency under the parameters of the EPA mileage tests, which the manufacturers know as well as the EPA, so no, you'll never get those EPA numbers in actual day to day use.)
The reason the hybrid concept has as much potential as it does is that electric motors have a far higher efficiency in terms of translating electrical power into torque, particularly with switching mode AC motor controllers and other high efficiency tricks, and typical battery technologies are around 70% efficient (measured as discharge/charge energy ratio), and having a battery allows the engine to be sized much smaller and in most cases run at steady-state power output while the battery handles the peak demand, so, for certain driving styles and trip profiles, the hybrid has a significant advantage. Hybrids require smaller engines because all the engine has to do is maintain charge on the battery at or below a certain break-even speed dictated mostly by drag coefficient. But how much of a differece hybrid vs conventional makes for any given driver or any given set of daily driving routes is going to depend on a fairly large number of variables, and this is true for both hybrid and conventional platforms.
So it's more complicated than just "enough hype" vs "not enough"/"too much"..
89 Corolla = 42 MPG freeway, 32 City and it's... (Score:3)
cheap ass.
Frankly, when I get 10 percent bigger wheels for it, I expect to hit near 50MPG on freeway. It's an old engine, throttle body delivery, with a simple mod or two to flatten out the timing advance system, allowing for more "sweet spot" time at cruise, with some small performance trade-off when driving at full driver demand.
I've had this car for way too many years, and total cost is about .12 per mile, inclusive of everything I've ever spent on it.
The ROI on Hybrids do not make sense at this time. Cool, if you want to early adopt and advance things, but not cool, if the goal was actually saving money on your driving.
If I could get new gears created at a cost that makes sense, I would skip the wheels and mod the rear end to put the torque curve more toward economy, stretching the gears out to make 5th cruise only, easily getting 50 MPG.
IMHO, hybrid cars suffer from complexity right now, and battery weight / performance metrics still are a bit too crappy to make any longer term sense. If we improve batteries, we can reduce complexity, significantly improving the hybrid value proposition. Still a ways off.
Maybe if we improve batteries in general, we could go with all electrics for many use cases too. Either is ok, and I could use either, given the value is really there. Today it isn't.
"normal" driving (Score:3)
I looked into the technology when hybrids were first becoming popular. I was concerned that starting and stopping the gas engine would result in heavy losses. Turns out not to be true. The type of engine used is very efficient at a constant RPM (which is where much of the gain is made) and doesn't appear to have a lot of starting cost.
The Prius arrangement (constant rpm engine charging batteries which provide variable speed and acceleration) works really efficiently in stop-and-go traffic. Where it falls down is constant high speeds over long periods of time. So for a commuter car in crosstown traffic, it excels. For a touring car, not so much. I think this might be the heart of many owners' complaints. Even with careful throttle usage, mileage drops like a dead bird on that 700 mile trip to grandma's
To owners of regular gas cars, hybrids are counterintuitive. My truck gets 17 to 19 MPG in town [1], 25 or better on the freeway if I don't change speed a lot and there aren't too many hills. A hybrid will tend to get its best mileage in town and mediocre-to-bad mileage on long freeway trips. This isn't a defect, it's how the technology works. You have to use the right tool for the job, and if the job is to spend the great majority of your time at freeway speeds, you need to pick a technology that works well under those conditions.
[1] The purpose of the truck is to haul large amounts of heavy or bulky stuff. My transportation of choice is motorcycle, which gets a little better gas mileage than a Prius. And is more fun. But won't carry four adults, unless they're really good at holding on.
Re:Here's the big thing... (Score:5, Interesting)
>
If I had space to park two cars at my house, I'd have an electric one as a regular vehicle, but with certain transportation needs, I'm not able to find them in an electric vehicle yet and I can't afford the conversion costs.
If you live in a city, one option to having 2 cars might be to join a city car share program. If you rarely need the range of a gas powered engine, it could be a cost effective alternative to owning two cars. Plus you can choose the car that best meets your needs - take a sporty convertible for a weekend getaway with your wife, take a minivan on the long trip with the kids, take a pickup truck to the hardware store, etc.
http://www.zipcar.com/ [zipcar.com]
http://www.citycarshare.org/ [citycarshare.org]
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I'd have an electric one as a regular vehicle
Better yet, buy a bicycle!
A bike is not always practical. Try commuting from Oakland to San Francisco on your bike (you can't take it on BART during commute hours).
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Every time I consider that option, I seem to see one of my two coworkers mangled by a commuter bike accident, and think: if that's the best plastic surgery can do, maybe I better be careful.
Re:Really? (Score:5, Informative)
And once the batteries are depleted, the car can no longer shut down its gas engine...
I live high in the hills, and by the time I'm at home the battery is usually on its last couple of bars. This is normal and it has no ill effects. In fact, the battery still retains about half of its charge at that time.
The author is clearly avoiding the truth here. Any Prius owner knows that his claim has nothing to do with reality.
By the way, the climb uphill is usually at 15 mpg, but the descent is at 100 mpg, and the average efficiency is about 43-45 mpg. If I stay in the valley for a long time (say, a whole day of driving with a meter reset) the efficiency will be about 52 mpg. That's with a 2005 (Gen.2) Prius.
For me, though, one of major selling points of Prius is not just its efficiency but it's CVT. The ride in Prius is the smoothest I every encountered, which is not a surprise because it has no gearbox that would switch anything.
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And I'm getting 53-56 MPG at the injector and 50-52 MPG at the pump (lower due to evaporation) on mostly highway commutes.
The calculation done by the car's computer is stupid. The "averaging" which is done by the car in computing its average MPG figure is a time average of the instantaneous MPG value. It should, of course be a weighted average using the rate of fuel usage as weighting factor to give a proper MPG average over a certain number of gallons (your pump figure).
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A hybrid can usually get BETTER mileage in city driving than on the highway. The system recovers energy every time you coast down a hill or apply the brakes (much like an electric locomotive's dynamic braking system does). On the highway the hybrid must run totally on the gasoline engine, unless the trip is short enough not to deplete the battery.