Tag Archives: mpg

Annals of Delusion: CNG and Mini Cars

If you’ve been following this site, you know that it is a core DbC thesis that automobiles are far closer to their right walls of perfectibility than their sponsors admit or the deluded fans of alternative fuels understand. 100 MPG is simply never going to happen in any car, regardless of its power source, that’s viable in sprawling, cars-first-transportation conditions. The laws of physics forbid it.

To wit, two pieces of news today:

According to this story in the online version of the Albany Times Union the compressed natural gas Honda Civic gets “38 mpg highway, 27 mpg city.” Converting cars to CNG, in other words, would burn up natural gas at the same rate as the better petro-cars now burn oil. Hardly a potential rescue for the status quo.

Meanwhile, here’s why physically tiny cars aren’t as fuel-efficient as you might expect:

NEW YORK (CNNMoney) — When most people look at really tiny cars they figure they must get really good fuel economy.

And when compared to trucks or family sedans, they do.

But subcompact and mini-cars — the likes of the Fiat 500 and Chevrolet Sonic — usually don’t get much, if any, better fuel economy than roomier compact cars.

For instance, at 33 miles per gallon, the most efficient version of the subcompact Chevrolet Sonic gets the same overall fuel economy as the larger Chevrolet Cruze Eco compact car. Other versions of those two models differ by only small amounts in combined city and highway driving.

Same for the teeny Hyundai Accent versus the larger Hyundai Elantra. Again, both get 33 mpg in combined city and highway driving. The subcompact Ford Fiesta actually does get better mileage than the compact Ford Focus. But the Focus, with 30% more horsepower and 43% more cargo space, gets beaten by just two miles per gallon.

It’s even true of hybrids. The tiny Prius C gets the same overall fuel economy (city and highway combined) as the larger Prius. Both are rated at 50 miles per gallon.

What gives?

Aerodynamics, mostly.

No matter how small it is, a car still has to hold people inside comfortably.

“You can shorten it up and make it narrower, but the height of a car can only be so small,” said Scott Miller, director of mass, energy and aerodynamics at General Motors, which makes the Sonic and the even smaller Chevrolet Spark, due out soon.

That means that, once you get past compact car size — the size of an Elantra, Cruze or Focus — cars start looking like tall boxes on wheels.

That’s not the best shape for pushing through the air. Slightly larger cars allow designers to refine the shape to better control airflow around the vehicle. Small cars provide less sheet metal to work with.

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MPG of Bicycles and Walking

einstein_bike Tom Murphy of Do the Math walks us through a topic that’s as crucial to the future of progressive, science-and-communications aided, modern society as anything could be: the comparative energy efficiency of human muscled-powered locomotion.

Corporate capitalism presumes the continuation — and, hence, the sustainability — of present mobility arrangements in at least its core areas. Under that arrangement, a large percentage of everyday, local-area travel is accomplished via automobile. This is due to the unique demand- and profit-stimulating effects (read: wastefulness) of cars-first transportation orders.

From an energy point of view, cars-first transportation means that fueling automotive engines is a major bottleneck for normal social existence. As such, the obvious question is how well does and could the cars-first arrangement compare to its major alternative, the reconstruction of towns and cities to encourage bicycling and walking?

Tom Murphy’s conclusion: On a diet of normal, mixed foodstuffs (rather than pure lard or some other means of maximizing the energy density of the comestible), short-distance bicycling yields an MPG equivalent of 290, or about 6 times the energy efficiency of a Toyota Prius. Walking, meanwhile, delivers about 160 MPG.

There is, Murphy says, one fly in the ointment here: the energy intensity of current agricultural and food delivery arrangements. Factoring that in, Murphy figures that the MPG of cycling drops to 130 and that of walking to 34.

einduh So, even without altering the food system (via increased organic farming, localization of supply chains, moves away from food processing/packaging, improvement of the veggie/meat intake ratio, etc.), bicycles are almost four times more energy efficient than Priuses, and walking is right in the same ballpark. A blend of the two — surely a main feature of any genuinely sustainable, modern human future — would be far more energy efficient than any conceivable cars-first arrangement.

(All this, of course, leaves aside the question of the energy required to build and maintain the infrastructures involved. Cars-first requires huge streets, large parking areas, scattered building patterns, and gigantic, ornate fuel-delivery processes. Muscles-first living would imply much smaller streets, less need for parking, dense building patterns, and comparatively simple fuel-delivery processes.)

Muscles-first would, of course, also be a far healthier arrangement: Using one’s own body, rather than 3,000-pound electrical or fossil-fuel combusting machines, to achieve the desired movements, would have radically positive impacts on public health, as would the accompanying reduction in exposure to the chemicals and large collisions involved in cars-first living and breathing.

Need we mention which society would be more fun and sociable and sane?

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Correction: Nissan Leaf Actually Gets 28 MPG

egg In a previous post, DbC reported that the miles-per-gallon performance of the Nissan Leaf was 38. Turns out this was a major over-estimate, as explained by physicist Tom Murphy.

If one focuses, as the peddlers of the things push and count on us to do, only on the charge-to-wheels aspect of the question, the numbers look very good. Murphy’s explanation:

How do electric cars or other electric/hybrids stack up? In order of performance: the Chevy Volt gets 35 miles from a 16 kWh battery for a consumption of 45 kWh/100-mi; the Nissan Leaf gets 73 miles from its 24 kWh battery for 33 kWh/100-mi; and the pricey Tesla has a 244 mile range using a 53 kWh battery, for 22 kWh/100-mi. The MPG equivalent of these three figures is approximately 80, 110, and 170, respectively. All are much better deals than gasoline cars deliver, primarily because the electrical drive system is far more efficient than the typical 20% gasoline engine.

The reality, though, is that charge-to-wheels is only half the process. What about production-to-charge, or the question of what it takes to put the power into the so-called electric vehicle’s battery? Murphy again:

In order to deliver 30 kWh to your house to fully charge the Leaf’s 24 kWh battery bank, for example—incorporating the charge efficiency this time, the source of electricity becomes a highly relevant factor. Two-thirds of our electricity comes from fossil fuel plants, typically converting 35% of the fossil fuel thermal energy into electricity. Only 90% of this makes it through the transmission system, on average. If your electricity comes from a fossil fuel plant, the 30 kWh delivered to your house took about 95 kWh of fossil fuel energy. The 73 miles the Leaf travels on a full charge now puts it at an energy efficiency of 130 kWh/100-mi. The MPG equivalent number is 28 MPG. From a carbon-dioxide standpoint, you’d be better off burning the fossil fuel directly in your car.

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Of Asymptotes and Asininity

prius-in-the-sky Led by Stepin Fetchit Obama, the overclass has just concluded another round of MPG charades. This time, they have reached a “deal” purportedly “requiring” car capitalists’ new-vehicle fleets to average 54.5 miles per gallon by 2025.

Given Big Money’s de facto ownership of politics in the United States, this is essentially an act of self-policing, so, of course, this “deal” is next to meaningless. As Automotive News reports, there already are two yawning loopholes.

First:

The Detroit 3 won a major exemption for their highly profitable full-sized pickups. The administration’s corporate average fuel economy proposal, details of which still must be worked out, would exempt full-sized pickups from any fuel economy increases from the 2017 model year through the 2019 model year, automotive representatives said.

Second:

Even for regular passenger cars, “the plan for 5 percent annual increases could be changed if a midcourse review, planned to begin in 2018, determines that it would adversely affect industry costs and vehicles sales.”

The main point of the whole endeavor, in the opinion of DbC, is actually not any kind of serious public control over miles-per-gallon. MPG is going to increase with or without any such “deals,” given the realities of Peak Oil. The real point of this kabuki is perpetuating a key mis-perception of reality: the notion that the energy efficiency of automobiles is merely a matter of human intentions and political checks-and-balances. Could MPG ever be 100, 200, 300, 500, 1,000? “Sure, if only the conservatives would wake up and smell the coffee, yes.” That’s the intended message for greens and liberals.

Of course, as DbC has always maintained, like everything else in the known universe, automobiles are subject to the laws of physics. As such, 3,000-pound metal boxes carrying humans at highway speeds can only ever get so efficient. Indeed, after a century of intensive corporate R&D and lavish public subsidy, it is DbC‘s position that existing cars are much closer to the asymptote of maximum efficiency than capitalists and liberal greens acknowledge.

If you doubt this claim, take a look at this excellent post by the extremely helpful analyst Tom Murphy. Murphy’s estimate of the actual top limit of highway MPG for cars that are usable under the cars-first conditions that prevail in the USA? 56 MPG.

Do you think the type of basic-physics analysis done by Murphy is unknown to the powers-that-be? That it’s a mere coincidence Murphy’s estmimate is almost exactly the promised ultimate MPG figure?

If so, I can still get you that excellent deal on the Brooklyn Bridge…

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Physics and Capitalist Fantasy

rube_tube Having everybody in the United States use automobiles to accomplish daily travel has always been a capitalist pipe dream. That is thanks to the laws of physics and the geology of our planet. It will simply never be remotely economical, sustainable, or sane to deploy 3,000 pound objects that sit idle 95 percent of the time to accomplish what walking, cycling, and public transit could just as easily (and much more safely and healthfully) facilitate. On a planet that was fated to reach Peak Oil, awakening from this pipe dream, one way or another, was also always inevitable.

A major side note to this story is the open secret that the basic physics of automobile travel are also far more fixed than present promises from above would have you believe. Just as an acceptable level of safety in a sprawling, cars-first society like the United States will always require cars to weigh something like 2,500 pounds, so it is that moving 2,500-pound cars will only get so energy-efficient.

Evidence of this physical fact was recently helpfully analyzed by Rick Kranz of Automotive News:

On the basis of vehicle weight, how dramatic has the increase in fuel economy been over the past 45 years?

This week I was running through some old news articles, seeking information for several stories I’m writing for Automotive News‘ special issue devoted to Chevrolet’s centennial. The issue will be published Oct. 31.

I decided to compare those cars to two 2012 cars with similar vehicle weight to see the differences in fuel economy, 45 years later. Obviously, the length, width and height of the 2012 models are somewhat reduced compared with cars in the ’60s. The new models have far better aerodynamics than the Chevy and Rambler. Additionally, the 2012s compared here have four-cylinder engines.

The 1966 Chevrolet Biscayne weighed 3,294 pounds and averaged 21.04 mpg. I used a base 2012 Ford Fusion sedan with automatic transmission for the comparison. The Ford weighs 48 pounds more than the Chevy and gets 23 mpg city, 33 mpg highway and 26 mpg overall, according to the EPA.

The 1966 Rambler averaged 23.80 mpg, coast-to-coast. For a weight comparison, I used a base 2012 Honda Civic with an automatic transmission. The Civic weighs 2,608 pounds, and is rated at 28 mpg city, 39 mpg highway and 32 mpg overall.

Using the EPA’s overall miles per gallon numbers, the Fusion was 5 mpg better than the Biscayne and the Civic was about 8 mpg better than the American.

Was there a dramatic difference in fuel economy 45 years later on the basis of vehicle weight?

Those numbers work out to about a 25% mpg gain for the heavier car and a 33% one for the lighter vehicle. So, despite three major oil shocks and the recent quasi-official acknowledgement of Peak Oil, automotive mpg has improved by substantially less than one percent per year since the days when everybody assumed Earth’s resources were infinite and mpg ratings were not posted on sales stickers or anywhere else.

Something to keep in mind the next time you hear some Democrat or other “green car” moron bloviating about 62 mpg.

As the late Stephen Jay Gould wrote, every human endeavor is subject to “right walls,” or outer limits of improvement. Here at DbC, one of our core theses is this: The automobile is already much closer to its own right wall than anybody will admit.

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CAFE Fraud

In the United States, government devotes great energy to helping the overclass conceal the multiple disasters inherent in cars-first transportation. The agency that tracks the tens of thousands of yearly deaths in car crashes and invariably reports them as good news? That’s the National Highway Traffic Safety (not Danger) Administration.

Hence, how surprised are we here at DbC by this report about the fraudulence of federal CAFE (Corporate Average Fuel Economy) mpg ratings?:

Under a 62 mpg CAFE rule, real-world fuel economy would be just under 50 mpg.

And if CAFE were 47 mpg, the real-world number would be about 38 mpg.

To know why, you have to understand what the CAFE number is — a sales-weighted average of the mpg ratings for vehicles produced in a given year. Vehicle mpg ratings are based on lab tests using a dynamometer, a sort of treadmill for cars.

Dynamometer testing produces an artificial number, but it does provide controlled conditions. No wind, no rain. And it allows for precise test protocols. For instance, the federal city-driving test cycle lasts 1,874 seconds, with an average speed of 21.1 mph, and has cold- and hot-start segments of 505 seconds each.

That’s where CAFE mpg numbers come from. But — here’s the curveball — those numbers don’t appear on window stickers.

In an effort to get closer to real-world fuel economy, CAFE numbers are reduced by 20 to 25 percent, depending on the type of vehicle. So a car that scores 35 mpg on the laboratory test will have a window-sticker rating of 28 mpg. [Source: Automotive News, May 9, 2011]

The obvious purpose of the continued use of a test known to be unrealistic? To make the “debate” on transportation among politicians sound more serious than it is, and to thereby shift attention farther away from the real issues, which continue to be utterly unmentionable in public fora.

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The MPG Hoax

donkey-car I often lambaste “electric” cars in this space. My aim in doing that, however, is not to lend aid and comfort to petro cars, which are, in their actually existing form, even worse than “electrics” and hybrids, from an energy-use perspective. I am against “electric” cars because they are halo-ware, a carefully planned distraction from the only kind of reform that stands a chance of bringing transportation systems into line with the requirements of energy and ecological sustainability. Converting to “electric” cars is something that directly competes with radical reconstruction of towns and cities to favor walking, bicycling, and public transit.

Yet, as a kind email commenter on my recent re-post at CounterPunch pointed out to me, it certainly isn’t enough to observe that the energy efficiency of “electric” cars is vastly exaggerated. The same is also increasingly true for petro cars.

The reason for that is the same as the reason I discussed yesterday in relation to “electric” cars: Assessing vehicle efficiency from the point of charging or filling excludes the huge energy expenditures it takes to deliver the charge or the fuel to the plug or the tank.

In the case of the “electric” car, the amount of energy (in the form of coal, natural gas, nuclear, wind turbines, or solar panels) it takes to produce an electrical charge for the car’s engine is significantly larger than the energy embodied in the delivered charge.

But just as (contrary to the childish suggestions of corporate marketing on the topic) electricity is not magic, neither is petroleum. Just as it costs energy to get electricity for “electric” cars, so does it costs energy to discover, drill, process, store, and deliver every gallon of gas pumped into an automotive tank.

In the past, the EROEI for petroleum was extremely high. Over time, as the easy and obvious reserves have declined, it has taken much more energy to discover and drill for petroleum. As a result, oil’s EROEI has plummeted and will undoubtedly continue to decline into the future.

As this happens, it becomes increasingly misleading to use MPG as the basis for evaluating the efficiency of petro-powered cars.

If we had an actual (rather than merely a nominal) green movement in this country, it would be pushing for a universal dust-to-dust standard for comparing the energy-use rate of various form of transportation machinery, including all cars, whatever their engine type.

That, of course, would be purest anathema to the corporate capitalist overclass, which is institutionally and psychologically addicted to perpetuating cars-first transportation right up and into Carmageddon’s awful dawn. Ergo, it is squarely off-the-table, even among the greens. They prefer gestures and pathetic photo-ops and going along to feel like they’re getting along.

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“Hitting the Mark”

earth v. money At this point, any sane society would be moving very aggressively to build its way back out of cars-first transportation.  Part of that effort would be steep taxes on gas guzzlers.

In the United States, where we not only don’t begrudge people getting rich, we don’t even allow them to be questioned, what are we getting?

This:

DETROIT — It’s diet time for the once best-selling SUV in America.

The redesigned Ford Explorer has been slimmed down for 2011 and transferred to a car-based platform. And it no longer will be a gas-guzzling hulk with a V-8 under the hood.

Ford Motor Co. said today that the redesigned 2011 model — equipped with an optional, two-liter EcoBoost I4 engine — will achieve a 30 percent increase in fuel efficiency compared with the current V-6-equipped Explorer. EcoBoost has delivered similar fuel economy gains in other cars and trucks.

The current Explorer equipped with two-wheel drive and a four-liter V-6 is rated at 14 mpg city/20 highway. With a 30 percent increase in fuel economy, the EcoBoost-equipped Explorer should deliver 18/26.

Eighteen miles per gallon.

In the car-pushing trade, this is what’s called “hitting the mark”:

“We believe we’ve hit the mark with the next-generation Explorer,” Mark Fields, head of Ford’s Americas unit, said in statement. “It has the potential to change perceptions of what a modern SUV is all about.”

In honest language, this is the same old same old:  Capitalists selling the largest possible vehicles, the planet and its people be damned. “Hitting the mark” means figuring out how much waste you can get away with under new conditions.

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SOS From Chrysler

This, ladies and gents, is what’s “new” from the Chrysler Group LLC.

This, “the first car to roll out since Chrysler’s alliance with Fiat”? An SUV! An SUV that “starts at” $32,995! An SUV that gets 16 MPG in city driving!

The ad? A ham-handed raft of stale jingoism, flattery, and deceptions, made by the always atrocious Wieden and Kennedy propaganda mill.

This much is screamingly obvious: “Our” overclass (and it includes the new Italian bosses) is simply and completely incapable of doing anything new, in even the slightest degree.

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