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CAFE stands for "Corporate Average Fuel Efficiency". In short, it means that the models of vehicles an automaker offers have to AVERAGE a certain number of miles per gallon. There are separate classes for cars-based and truck-based vehicles -- truck standards are lower. So if you have a pretty-big "crossover" you'd like to sell, make sure it meets the definition of a "truck" and life is a lot easier. This is a fact which many have pointed to for abetting the death of the big car and the outrageous popularity of SUVs until the last few years. Some lawmakers are talking about eliminating this distinction, which seems like a good idea to me. I think anything you can drive without a commercial license should be lumped into one pool.
I don't comprehend all the ins and outs of the law, but one key is that it doesn't matter exactly HOW MANY of each model you sell -- you could sell a few ultra-efficient Model 1s and a million gas-guzzling Model 2s, and as long the average of those two numbers is over the CAFE standard, you're golden.
Warning: Math ahead (but it's easy)
The fundamental flaw with "miles per gallon" as a measuring stick is that it looks like a linear measurement, but it's really an exponential measurement of gasoline usage. Instead of asking how many miles per gallon a car gets, ask how many gallons it requires to go 100 miles, and you'll have a much better idea of what it will take to keep that sucker running. As a simplified example, let's start by considering a hypothetical 16-cylinder muscle car that gets 5 MPG. It would take you 20 gallons to drive from Ann Arbor to Flint, MI.
5 MPG x 20 gallons = 100 miles
Ouch -- that cruise will set you back 60 bucks. Next, let's take a big SUV that gets 10 MPG:
10 MPG x 10gallons = 100 miles.
(100% improvement in MPG)
Okay, so this vehicle took 10 gallons to get you to grandma's house, and that would run you about 30 bucks. But you saved 10 gallons of gas -- that's 30 bucks cheaper than the hot rod, and you've only done half as much damage to the planet. Let's compare that to a small pickup that gets twice as many MPGs, and therefore uses half as much fuel:
20 MPG x 5 gallons = 100 miles.
(100% improvement in MPG)
As you'd expect, it's half as expensive -- about 15 bucks at today's 3$/gallon gas prices -- to drive this vehicle. But take a look -- Even though this looks like a much bigger jump in MPG than going from a 600 hp hot rod to a behemoth SUV, you've only saved HALF the gasoline. This 10 MPG upgrade saved you 5 gallons, and $15. Over the life of the vehicle, upgrading from a big SUV to a small truck is like taking another 20 MPG truck off the road forever! What if we went for something mid-sized?
30 MPG x 3.3 gallons = 100 miles
(50% improvement in MPG)
OK, This 10 MPG upgrade saved you 1.7 gallons of gasoline, or just 5 bucks at the pump on a trip to Grandma's. That's still a combo meal at Wendy's, but you're not feeling as brilliant as when you sold that titanic SUV to get your little pickup truck. With savings like that, why consider the extra expense of a little hybrid?
40 MPG x 2.5 gallons = 100 miles
(33% improvement in MPG)
So what? You would save a measly .8 gallons of gasoline on this trip, and while driving a high-tech car would make you feel good, that only saved you about $2.50, and doesn't make all that much difference to the planet, compared to a midsize sedan. At this point, you're really not using all that much gas. In our example, if six people upgraded from mid-size cars to hybrids, that still wouldn't save as much gasoline (4.8 gallons) as ONE person upgrading from a 10 MPG to a 20 MPG vehicle (5 gallons).
If you're buying relatively fuel-efficient cars, there's just not that much gasoline to be saved, and thus, not that much money to save. Consider this another way. How much is a 10% improvement in mileage worth to the driver of a 10 MPG SUV? That's 1 MPG, and on a 100-mile trip, that would save almost 1 gallon of gas, or just under $3. For the driver of a 40-MPG hybrid, that 10% jacks his mileage to 44 MPG, which sounds impressive. But he's only saved himself 1/4 of a gallon, or about $.75.
Yeah, it adds up -- but it adds up pretty slowly.
Now, look at this same situation through the eyes of an automaker. He's not worried about how much GAS you're using, he's worried about the MILEAGE number. In his CAFE equations, that 1/4 gallon of gas saved by the hybrid driver is worth MILLIONS because that's an extra 4 MPG in his pool of numbers to average out. But a 10% improvement in a dinosaur-sized SUV may only be worth 1 MPG, even though that represents almost a whole gallon of gas over 100 miles!
Still, slapping a hybrid motor in a tiny car to squeeze out 5 or 10 extra MPG enables that automaker to jack up the horsepower in several other (more profitable) vehicles, and still come out even on the CAFE standards. What a great shell game!
People have talked about the holy grail of a 100 MPG car. Frankly, who cares? The low-hanging fruit here are the huge bus-sized battering rams that people are driving around with the hand that isn't holding their cell-phone. We should be finding ways to put hybrids in the big SUVs, not in the already-frugal econo-boxes. That's where the gas savings are.
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18 comments:
There is already development in asian automakers to make SUV's much more fule efficeint than their american counterparts.
The first step was to use a modified auto chassis instead of the larger heavier converted truck chassis that the american automakers use. This is (i think) the biggest and cheapest fuel saving step. Also the asian automakers development of more fuel efficent engines is far ahead of ours.
I think for too long a time american automakers were stuck in the mindset of "bigger is better". We're playing catch-up now.
Also, no one wants to hear this (including me) but no matter what car you are driving, fuel efficiency skyrockets when you maintain your speed at a certain velocity (usually 45-55 mph).
-Marty
One further consideration is the energy requirements to actually build a car. I have heard it quoted, though I don't know what the calculation entails, that the manufacture (including producing raw materials I assume) of a typical car (be it hybrid or Hummer) is of the same order of magnitude as its entire lifetime fuel usage on the road. Also, it is helpful to look at the tremendous consumption of energy that goes into building and maintaining the car infrastructure.
While your point about how fuel efficiency is computed is well taken, I think it misses the point. As I have said before on my blog, cars are not part of the long-term solution to our energy crunch. It doesn't matter how efficient they are, or if they run on domestically produced "renewable" fuels. The widespread use of the private automobile is what got us into this mess, and continued use of even refined versions of the automobile is unlikely to get us out of it. In fact, I'd go so far as to say that increased efficiencies and various "environmentally friendly" fuels serve only to exacerbate the problem by promoting continued complacency and reliance on mythical techno-fixes. In the meantime, the options become even fewer.
In terms of the political realities of this, the right is hung up on some perverse notion of the personal freedom to live tens of congested miles from work and drive a 10 mpg tank everywhere. The left, more disappointingly to me, seems to have hitched itself to this abstract notion of a "Manhattan Project" that will somehow help us to overcome the pesky limitations of thermodynamics with things we can grow on family farms. When I stand back and look at it, both ideologies are based on the assumption of the universal right to the private automobile.
Any serious solution to our energy issue will displace the continued use of private automobiles as a primary, secondary, or tertiary constraint.
Good comments, guys.
Until we reach the point where our massive installed transportation infrastructure becomes obsolete, improving fuel efficiency is still a worthwhile goal. When you buy an appliance, the government requires it bear a sticker estimating its annual energy use and cost to run. It's a pretty straight-forward metric. With automobiles, there's this weird inverse-exponential number called MPG which requires some mathematical gyrations to come up with an estimate of what it will actually cost to run... An estimate which, due to the crappy system the government uses to estimate MPG, won't be that accurate anyway.
I agree that your method of reporting fuel efficiency is more informative than the CAFE method.
But...
I would suggest that increased efficiency (or alternative fuels) is the moral equivalent of the healthier cigarette. Many smokers of "light" cigarettes have tended to believe that they were doing less damage to themselves than they would by smoking the full-strength stuff. In reality, and probably by design, this delusion allows people to continue smoking, or even increase the number of cigarettes smoked, when they may have otherwise done the only truly prudent thing and quit smoking altogether. Now the political spectrum is dominated by people who say the equivalent of "keep smoking, it's healthy" (the right) and those who say "we demand healthier cigarettes" (the left). The people who say "quit smoking" are regarded as fringe nutjobs.
You mentioned the car-infrastructure becoming obsolete, but I'm not sure I know what that means. CFCs in spray cans are now obsolete, not because they failed to meet our needs as spray can propellants, nor because they became scarce and unaffordable, nor because they were supplanted by a technologically superior product, but because we recognized that they posed a long-term threat and quit using them. I suspect 'obsolete' in this case means that the infrastructure will become too expensive to use and maintain because we have squeezed the last affordable drop of petroleum out of the last accessible reservoir. I personally think that we should find serious solutions before this happens, rather than look for ways to push ultimate depletion a few years down the road.
my bicycle gets about 18 miles to the pint, I'm no math genuius, but thats 144 miles to the gallon. If automakers really want to "pad" their average mpg, they should start making bicycles.
Agreed. I have always found it inconsistent that big cars adn SUVs qualify as "commercial" vehicles when the majority are used to haul around nothing more than gaggle of kids and their appurtenances.
I do not have a fundemental issue with the idea of "commercial" registration for vehicles, however, I believe it should be attributable to vehicle USE rather than vehicle TYPE. My suggestion would be that "commercial" registrations be issued to valid "commercial" registrants.
In other words, XYZ contracting may register a vehicle as "commercial" in the name of the business, but the soccer mom in the Suburban or the "outdoorsman" pulling his bass boat with the Ford F250 should only have the option of registering their large vehicles as "passenger" vehicle. The vehicle USE of these latter examples being unarguably for "passenger" and personal use.
The upshot of this, in my opinion, is that changes to the motor vehicle registration rules will close the loophole that this blogger notes. Once the large SUVs and trucks are no longer exempt from CAFE standards, there will be no quantity of hi-tech hybrid cars that can offset the guzzling of the large trucks...eradicating the basis that the shell game can successfully be played.
Full disclosure...I live in a 2-car, 2-hybrid family. And while I recognize that the overall fuel savings that my wife and I are actually affecting, our driving these vehicles does provide more exposure to the issue that we need to look at efficiency. Which may lead into the discussion of how UN-sustainable the petroleum economy is...but let's leave that for another discussion, shall we?
I can't help thinking that Dan Devine is probably right, that as long as Americans can afford to indulge in the luxury of cars and trucks, they will --- and it truly is a luxury to have such freedom of movement, the ability to stretch ourselves such long distances. And, if an effective substiutute for oil comes along to extend the automotive run, then Americans will seize it.
The limiting factor, though, may not simply be the pressing down of some dictatorship, it may be the planet itself which slings off its human burden. Is it possible that day is close at hand?
I love all the commentary, and am now more jealous than ever of Jim's prodigious blogging abilities -- one reference from him, and we're temporarily "big time!"
But I can't help pointing out that regardless of what Jim thinks people need to do, tomorrow morning, 150 million Americans are going to go out, get in their gasoline-powered car, turn it on, and drive to work.
Changing CAFE standards DOES matter, and changing the way we measure it is, to my mind, a simple "truth-in-advertising" measure that would greatly help in educating people on how much gas they are actually using. It's much easier to make good policy when you have a rational grip on the actual costs and benefits of your various choices.
Frankly, as much as your suggestion makes sense from a truth-in-advertising perspective, I don't think it will make much difference in the actual number of gallons of gas burned in the country. The fact that reworking CAFE standards may be more politically palatable than whatever I suggest does not mean it will be effective in achieving the goal of reducing fuel consumption.
I'd prefer to see the price of driving more accurately reflected in the price of a gallon of gas, regardless of whether that gas is to be burned for private or commercial purposes. For starters, I'd tack on the full price of building and maintaining the infrastructure onto the gas tax and remove it from other taxation sources. That would do more to improve the efficiency of cars than would reworking the numbers about how we compute that efficiency.
Jim, you're getting into the finer points of economic calculations, and I'm not in any position to crunch those numbers. But I think you're setting this up as something of a false choice: I don't think our points are exclusive -- you can reform fuel-economy metrics AND the tax structure, and perhaps we should do both.
As we head into the next generation of transportation systems, though, gas taxes may not fully answer, because alternative-fueled vehicles will use the roads and require signage, plowing, lights, etc. just as fossil-vehicles do.
I do think it's worth pointing out that the vehicles we have are partially a function of fuel-economy legislation. The popularity of SUVs began to boom when automakers begain tailoring vehicles which could be labeled "trucks" for the family passenger-vehicle consumer. Before CAFE distinguished between cars and trucks, the emphasis of SUVs was on the "utility" part.
Incidentally, I don't think my idea is all that politically palatable. The people who really care about such things tend to be poorly paid public-policy types and very well-funded automakers, and the general population just doesn't feel any passion on the issue.
As for the ultimate question -- would improving fuel efficiency actually decrease gas consumption? -- I guess we basically disagree. Unequivocally, I think, yes.
Oh man! I wrote (with considered thought and eloquence) a posting - and due to my ineptitude - it's disappeared. We have the same problems with SUVs here in the 51st state. Even in the inner city where public transport is available and reliable, every other household seems to own one. Their main purpose is to tranport precious little darlings to school (which is normally less than a mile away). Apparently it is considered irresponsible to allow children to walk to school - they might be abducted (aliens being the most likely culprit). In summary, I agree with both Jim and Scot, but Scot's initiative would simply be a drop in the bucket. If Scot considers his ideas as not politically viable, then Jim's have no chance. My conclusion was that we are doomed unless we find a Green Dictator. We need a Green Dictator to ram changes down people's throats - changes to our attitudes about transport, changes to living and working arrangements, changes that normally would take generations. I'm going out to buy a wig now.
I'd rather let my engine idle than read a bunch of idealistic ideas on how to stop Americans from driving (or at least penalize the ones that due). The truth of the mater is Americans are more than addicted to their cars; they are in a position where consumption is the only option. We live in a world where urban planners don't even consider transportation options other than the single passenger vehicle. Highways and toll roads are the norm in the inner city urban plan. Snake mazes litter our suburban landscape. Most of us life more than ten miles form our jobs. The grocer is at least a couple miles away. Childcare is another issue in itself. Back to the issue at hand, automobile driving, both the operation, and the system in which it operates is expensive. Jim is completely correct. We need to tax drivers to support the infrastructure they operate in. We also need to take a corporate branding approach to get Americans to think favorably about things like cycling, buses, or the train as a form of transportation. Think about it, people shop at places like Starbucks, Best Buy, and Target because of the experience, regardless of the price they pay. What they take from their shopping experience determines the worth of the cost. People buy Toyota, GMC, or Apple because of the experience they perceive they will achieve with the product they buy. The consumer lifestyle the privileged American lives justifies their purchases, and the infrastructure they operate in decides what options they have. Only a noble few would buy a more fuel efficient auto if they can afford the one they currently own. Especially if the one they own produces some sort of experience they feel they may be denied in a different car. The solution to the problem lies in a fundamental shift if American Ideals. I stress the American Issue here because many nations are following our corporate consumer culture business model. It’s proven to be financial successful. The question is; is it socially successful?
In the mean time I'm going to ride my bike over twice the miles it would take me to drive because I'd get a ticket (or die) if I rode my bike on the roads that lead directly to anywhere. Mark my words, the automobile will be the end of a favorable American lifestyle. I’m not trying to be preachy, but I’m not apologizing if I do. Quite your car addiction while you can.
Hybrid cars saves gas but not money. I would like one but for me a little econo box makes more "cents".
You're right, Adam, infrastructure is a problem in many areas. People have a lot more control over it than they might think though. Contrary to what you say about highways and toll roads, I'd argue that it's easiest to live without a car in the inner city. Cities generally have the best public transportation options (most of the time, there are certainly exceptions) and the higher density that makes it possible to live and work and shop within a radius of a few miles. The problem is that this is rarely made a priority.
For most Americans, the price tag for something is the primary, and sometimes only consideration, but this is often short-sighted. Choosing a cheaper & larger suburban home ignores the extra transportation cost in money and time to get anywhere you need to go. Choosing to commute by car because the bus or train seems too expensive ignores the cost of the car + depreciation + insurance. If both parents in a family need to work (out of desire or financial need), there's childcare expense and travel.
Take all of these things into consideration though, and you can make better choices that allow a simpler life. Americans aren't used to thinking beyond the immediate price or consequence, but it's time to open our eyes to the bigger picture. The America lifestyle has been on borrowed time since the '50s. The more of us that make the conscious decision to scale back now, the better the odds for the next generation.
re: Bilc's comment.
There are quite a few things we do in our household to try to help the situation, as bilc recommends, and we hope everyone will find ways to do that. But ultimately, there has to be a bigger effort. Such things take the time and attention of those who govern, and while they are tied up in some friggin' war or meddling in other such messes - and finding ways to aggregate the wealth of those who're already wealthy - they don't have time or money or energy to tussle with the ecological crisis which is banging on the back door.
BTW: my wife and I were discussing the fact that many many people own these monster SUV's so that they can drag monster campers (i.e., small homes) into the forest and start up their generators and televsions out in 'nature". Now is this a compounding of silliness? And these hundreds of thousands of folks do it because they can afford to do it.
So: Yes, one thing society should start to do is heavily tax those folks for their excesses.
Very relevant points you're making about the fleet of vehicles on the street today. I agree that the minimum thing a person with a conscience can do is not buy a large truck or SUV for general transportation. Getting these off the road, is definitely the low hanging fruit.
A couple points to think about:
- Both measurement systems you describe are just as linear. The advantage of the new system you describe is that the numbers might be easier to relate to every day life. Seems like a good thing.
- The advantage of a compact car over a mid-size only looks small because you're comparing it to a poorly designed vehicle, an SUV. The measly 0.8 gallons is really huge in terms of percentage! And if gas cost more, or you were driving further, you would care.
- As for the efficiency measurement making any big difference, the experiment has already been conducted! Just about every country outside the US and maybe the UK, measure their fuel efficiency in L/100km, much like your gallons/100miles. In Canada, people drive vehicles only slightly more efficient than Americans, probably because Canadian gas prices are slightly higher.
CAFE needs a major overhaul to get rid of the exception for SUVs. However, in the end, the real choice will be made by the consumer, and the biggest impact would come through an increase to gas prices. (in my opinion, that should come through a significant tax, maybe 100%, directed to real costs of driving as Jim suggested, but that's another topic)
Hey guys. Some good thoughts. I'll check in on ocassion now that OIFS has been trashed.
laters
Darren J, I love the thoughtful comments, but I have to disagree. You said:
"Both measurement systems you describe are just as linear. The advantage of the new system you describe is that the numbers might be easier to relate to every day life. Seems like a good thing."
Well, no. MPG is a linear measurement of distance you can go on a gallon of gas. But it is an inverse exponential measurement of gasoline used. Every doubling of MPG uses half the gasoline of the previous doubling. Therefore, every tick up the MPG scale is NOT equal, and there is a harsh diminishing of returns as you push past 20, 30 or 40 MPG. As my example shows, 1 MPG at the top end of the range represents a tiny fraction of the fuel used by 1 MPG at the bottom of the range. In short, I believe it is a PR stunt and a way of deceiving you as a consumer.
You wrote: "The measly 0.8 gallons is really huge in terms of percentage!"
Well, it might be a significant percentage of YOUR fuel use. But as a matter of public policy, it is NOT a significant part of our national useage. What sturck me was the fact that one person upgrading from a 10 MPG vehicle to a 20 MPG vehicle saves as much gasoline as SIX people upgrading from 30 MPG to 40 MPG. So if you're a policy-maker trying to cut oil useage and carbon emissions, what do you target?
"In Canada, people drive vehicles only slightly more efficient than Americans, probably because Canadian gas prices are slightly higher."
Well, sure, but Canada isn't the only data point. Europeans, I'm told, meausre efficiency in liters/100km or some such. And of course, they drive much more efficient vehicles all around. I guess my perspective is that markets require transparency and good information, and if customers were armed with accurate information rather than cooked numbers, they'd make "greener" choices even if we didn't change gas prices one cent.
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