Fuel Economy vs. Fuel Efficiency

With the energy bill now pending in Congress, many have questioned the viability of the gasoline fueled-internal combustion engine in cars, citing incremental mileage gains of the past few years as proof the technology has reached its zenith. - Dan Hancock

I'd argue that the reason we've only seen incremental mileage gains in recent years is because there wasn't any reason for car companies to improve fuel economy because fuel economy standards hadn't been substantially increased since the early 1980s.

The difference is the Tahoe and Yukon seat eight and can tow up to 6,200 pounds. - Dan Hancock

That's great... if you regularly carry eight people and/or tow 6,200 pounds. Most people don't do that. And I for one would rather have a car that gets over 40 mpg than one that could tow both of my current cars at the same time while carrying my entire family and my in-laws. Oh, not to mention it costs half what I paid for my house.

The Saturn Vue Green Line Hybrid returns for ’08 as the SUV with the highest highway fuel economy. - Dan Hancock

Which is great... if you're in the market for an SUV. If, on the other hand, you're in the market for a compact or small midsize car that gets over 40 mpg, like I am, you drive right on past the GM dealership.

It's pretty obvious that GM was caught flat-footed in terms of fuel economy. Hybrid sales are up 82% over the same month last year, and the Prius, despite being "ugly" and "small," is still the most popular hybrid vehicle and is selling more than twice as many this November as last November. (Source) GM had no hybrids for sale in November 2007.

Will these new hybrid SUVs gain traction? I don't think so. People who buy a Yukon or an Escalade aren't doing it because they want to save the planet or save gas money. They're doing it because they want a big, heavy vehicle. It remains to be seen whether they'll pay extra $10,000 for the hybrid, in the case of the Yukon. But it's nice to see GM doing something.

Hopefully we'll see this dual-mode hybrid system in something like the Astra (*sigh*) or the Cobalt sometime before the end of the decade. Then GM will have something that will give the Prius, Civic, and the new rumored Honda hybrid a run for their money.

Indeed, GM is working very hard to squeeze more miles out of a gallon of gasoline and reduce emissions. HCCI technology is still in the experimental stage, but we are confident that it will be one of the fuel-saving technologies we will offer customers in our future product portfolio. - Dan Hancock

The next car I buy is going to be a 2007 model, which will be in a couple years. And it's going to be something that gets more than 40 mpg. Nothing in GM's 2007 model year meets that criterion.

The next vehicle after that will be something that gets over 50 mpg, and will be a 2011 or 2012 model year vehicle. Hopefully by then GM will have something that I'm in the market for. And unless I move between now and then, or my city eases up codes about running extension cords up and down my block, a plug-in hybrid won't work for me.

I'm especially excited about HCCI. I'm curious as to how expensive it will be though, and if we can expect to see it even on economy cars such as the Aveo and Cobalt.

Also what ever happened to the 3 valve HV engines? The HVs already have a nice balance of power, efficiency, and cost. I'd like to see them continue to be improved.

Awesome news. I'm loving the AFM, and Direct injection techs the most. And I am looking forward to watching the Camaro rule the Sport Coupe segment by using these advances.

I do have one question. And perhaps you can't answer it, or maybe you can. A few months ago, Ward's Auto released an article about a new DI V8 6.2 liter engine from GM. Even in prototype form, does this engine exist? Because based on what was said in the article. It is a revolutionary V8. And I applaud it.

Other than that, I say good job, GM! And keep it up!

I applaud you and your team on the advancements you guys are making to the automobile. With the talent at GM Powertrain combined with a now reinvigorated GM Design the world's roads will no doubt be occupied by an ever increasing number of vehicles by General Motors.

Dan,

The only thing you have really been successful at is squeezing more and more out of your suppliers. And when there is nothing left to squeeze, you toss them like yesterday's news and look for a fresh batch to squeeze.

Hope it all works out for you with your quest to build the cheapest car in the world. Why not just move your entire business to China? Surely there are more gains there, right? You don't seem to need American business anymore, so why should American's buy your junk product?

This blog post typifies what is wrong with the U.S. auto industry. By your account, the mileage rating for these cars has barely crept upward in 20 years. Yet you pat yourself on the back. You cite added weight as mitigating factor. But surely new, lighter materials used throughout vehicles more than offset the weight gains incurred by things such as air bags. If not, something is wrong. 30 mpg was laudable 20 years ago. That automakers haven't blown past that mark with gasoline engines, or developed another form of powertrain is shameful.

Dan,

It is wonderful that GM has made such strides in fuel efficiency. I wonder about something in your comparison though, that you touched upon, but didn't directly address: the weight penalty. What would be the fuel efficiency of today's drivetrains if they only had to haul around the weight of a vehicle from 1988? That's a comparison I would love to see.

Also, can we expect an update on some of the advanced materials that GM is working on to both save weight and improve aerodynamic efficiency? I know that active aero as well as other uses of advanced polymorphic materials have been discussed for the last couple of years.

here's that you should do... move forward your plans for HCCI engines. You could partner with Daimler to reduce the cost of the transducers. HCCI engine is a competitive tool to defeat the Japanese, and at the same time increase fuel efficiency and CAFE dramatically. You could also stop selling Aveos at a loss.

My next car will be all electric. I hope it will be an American car but I doubt that it will. Mitsubishi and Suburu are suppose to come out with an all electric car in 2 years. GM produced the EV-1 15 years ago. This car was fast, could be charged at home, go 120 miles between charges and meet the needs of 90% of the driving public. Why did GM stop producing the answer to all our needs? It would solve our oil addiction, reduce global warming, stop funding terrorist,reduce trade imbalance, etc, etc. THE FUTURE IS THE ALL ELECTRIC CAR, and if GM doesn't get on board, the Japanese will dominate the world's auto industry.

Harry

The old cavalier weighs in at 2359lbs, the new cobalt weighs in at 2780lbs. If the new Cobalt could reduce its weight by 421lbs to the same as the 88' cavalier without reducing the structural integrity or quality if materials....how much better fuel economy could you squeeze out of that car??

We would strongly consider the Vue Hybrid when we replace our GMC Envoy XUV in the Spring, but it lacks a near-must-have feature for us, memory seats (no Vue has that.) Also, in general it doesn't allow full premium content, like an upgraded stereo and nav are off the Green Line option list. Who makes insane decisions like that in GM? Is there the assumption that people interested in gas mileage would only want a cheap radio??

And with so many couples sharing a vehicle these days, not offering seat/mirror memory on a lot more models is a real lost opportunity. Sure we could get all those features in a Yukon or Tahoe hybrid, but we don't want a vehicle that big and the gas mileage only goes from guzzling to acceptable. It seems like GM throws darts landing high, low, and to the side, and never hits the sweet spot target. We may go 9-3 SportCombi, but the mileage is so-so and the reputation for rattles has me concerned.

I think GM is about 90% of the way there in terms of providing sensible, fuel efficient cars to the masses. I rented a 07' Malibu on a trip to Hawaii. Surprisingly, the car got close to 32MPG the whole trip. Despite that, the car was rather bland and uninspiring, and as much as I hate to say it- Cheaply built. That said, the new Malibu that replaces it seems to be much improved. I'll have to rent one of those as well sometime.

Anyhow, I echo the sentiments of Paul. I also think that by making SUV's more fuel efficient by offering hybrid versions is a mismatch in marketing.I see where the logic lies: SUVS are the best-selling cars in America, hence making hybrid versions must surely be the right step. Let's not fool ourselves. People that buy big cars and trucks probably don't really care about what kind of hybrid technology it has nor wants to be associated with saving the earth.

Cars and trucks are more like fashion statements these days, and the best-selling hybrids are distinctively different and quirky looking from their more pedestrian counterparts. So while a Hybrid Malibu is a step in the right direction- more so than hybrid Escalade, I believe that a purposely built hybrid would be more on the order. Perhaps the Volt will fulfill that need.

Anyhow, I very much look forward to more news on the HCCI engine. Keep up the good work!

Mr. Hancock

I applaud GM's work on the HCCI engines. But why has GM decided to make its customers wait for high mileage technology?

Sure the newer GMs get the same millage and the older ones and weigh more while delivering more power. Why has weight increased so much? Isn't it possible to make a lighter weight low end car?

Additionally wouldn't it be easy to combine some of the higher tech now technologies to offer even better mileage? Such things as diesel electric hybrids. I find it tough to believe that GM can't bring over a few of their sub 2.0 L diesels for the Cobalt and Malibu and use them as hybrid electrics.

Additionally I don't quite understand why GM doesn't offer Flex Fuel in all their gas vehicles, how hard is it to really add?

And on the note of bio fuels. I would love to hear GM's take on the costs of using E85 (visible and hidden costs), producing E85 etc... is E85 a fuel that’s viable for the next 5 years?

What about bio diesel in GM engines, why haven’t' they been outfitted with parts to let them run higher concentrations?

What about the future of fuel cells, and hydrogen? Would Ethane/Methane be a better solution?

You seem like the correct person to address these questions to.

Additionally as a PR topic I would love to hear more details about the GM power terrain parts. I would love to know what makes the new automatic and manual transmissions better then the ones of the past (which tend to not go much beyond 90K miles in my experience). I would also like to hear how GM's VVT technologies work on the new CTS engine and whatever other engines use it.

I would be interested to hear about the new all wheel drive systems, the stability and traction control systems. I have found a lack of technical information about some of the latest GM engines and transmissions.

Additionally I have an idea on making GM automatics more fun to drive should GM be interested they can e-mail me.

Dan,

Congratulations on the fuel efficiency improvements over the last few years. Before you get too smug, however, let me point out that the competition is not standing still. Case in point: in a recent Edmunds' comparison test of the Malibu LTZ vs. 3 competitors that included the new Accord, Camry, and Altima, the Malibu had:

-the highest curb weight, despite having the least amount of optional equipment

-the largest engine displacement but the lowest rated horsepower

-the worst EPA fuel economy

And another point, the new Saturn Vue XR AWD weighs over 4300 lbs and gets 16 mpg. Pretty embarrassing when you consider that a fully loaded AWD V6 Ford Escape weighs nearly 800 lbs less and gets 3 mpg better city fuel economy (but I'll grant you that the Vue is much nicer and performs better).

You say "GM once again leads the U.S. industry with 15 models that achieve 30 or more highway miles per gallon", but considering that GM has more models than anyone else to begin with, that's not saying a whole lot, is it?

GM needs to be the fuel economy leader in every segment of the market if it really wants to be acknowledged as an environmental leader. Based on your recent model launches, it is clear that you have a lot more work to do.

Dan Hancock said: "And, in 2008, GM once again leads the U.S. industry with 15 models that achieve 30 or more highway miles per gallon. This is a very impressive accomplishment, especially considering the more stringent method that the EPA began using in 2008 for calculating fuel economy labels."

Mr Hancock,

Perhaps not that impressive since even the new, more stringent EPA calculations don't seem to deliver the truth.

A few weeks ago I had the chance to drive a 2008 Impala on a 270 mile trip on the Intersate.

The EPA rated highway mileage for that model is 29 mpg. I was only able to get only 22.7 mpg (per the Impala's on-board computer) traveling smoothly and at the speed limit.

Either something was wrong with the computer, or the car was performing far below specs.

If even a vanilla Impala gets that far below the EPA numbers, why should I have any confidence in your claims about how good the mileage of GM's cars is getting?

Regards,

Gary Dikkers

JL,

Well stated. I know GM wants to market their cars well but really are they blind to the industry around the? Could this explain the troubles they have and declining customer base?

C'mon GM we know you can do better.

Diesel Accord in 2009
40+ MPG city, 60 MPG Highway.
GM, where is your diesel Malibu? Diesel Astra? Your company can make them as shown by the Opel diesels, but your US company is not interested. Your company is more interested in fighting US consumers, than giving them what really want. Good luck selling your truck,and SUVs, which are proabably the best in the world, but unforunately are becomming obsolete before GM can make the platforms profitable. The world doesn't want them and the US consumer is about to be bowled over with European and Asian diesels. I want GM to be succesful, but your corporate attitude is still twenty years behind the times. (although closing the gap, I must honestly say.) The good new? Toyota has become the moribund 21st century version of 1970 GM. Take advantage of their lapse in judgement and get the right product to the consumer. One last thing, you got rid of FIAT at precisely the wrong time!

"Sure the newer GMs get the same millage and the older ones and weigh more while delivering more power. Why has weight increased so much? Isn't it possible to make a lighter weight low end car?"

Small cars weigh more because they are more rigid and better equipped then their predecessors. It's quite simple actually. PEople demand that even small cars are safe and refined today and thus weight goes up. The lighter cars of 20 years ago would be laughed at by today's customers due to their lack of safety features and equipment. Everything that people demand these days adds weight to vehicles.

As for diesels from Europe- most wont meet emissions here. You cant simply transplant engines from Europe into this country. On top of that diesels are more expensive to buy and unlike Europe we dont have tax credits available to those that buy a diesel.

JL:

Nice use of the facts to make your point. No mention of the fact that the Lambda SUVS get better mileage than Highlande ror Pilot in spite of being much larger. No mention of the fact that Tahoe/Silverado get better mileage than their Toyota or Nissan counterparts. No mention of the Two mode hybrids that will get at least 40% better mileage than any of their gas only competitors.

The Malibu V6 gets slightly less mileage than the Accord and Camry but the i-4 (which is what makes up most sales in this class) is right there in spite of having only 4 speeds in the auto. The 6 speed Malibu LTZ I-4 should exceed the mileage of the camry and accord four cylinder models.

How about an Aveo that gets the same mileage as a Yaris, or even a Fit. I wiould buy that.

Will the new 5 door Aveo get any better mileage than the one it replaces?

Thanks for a great article. Future propulsion technology is a tricky issue. Trans-Atlantic ships are no longer powered by wind, and Pan-Pacific aircraft are no longer powered by propellers, yet automobiles are still propelled by mere evolutions of the same external combustion engine they have been powered by for the last 100+ years. It seems progress in the automobile industry is slower than the rest of the world of transportation, and even technology as a whole. Yet the whole immense infrastructure to support private automobile use on public roads is what makes it difficult to change. Because the path to alternate energy sources is uncertain at this point, it is not wise to put all of your eggs in one basket, yet without getting unified support behind one solution we'll never be able to really change. While the argument for new CAFE regulations and the hysteria over global warming may be absurd, the issues of air quality and the petroleum supply and pricing are convincing reasons to look for new ways to power our cars; new technologies that are clean, renewable, and that aren't controlled by our greatest enemies.

paul one thing you are forgetting when a lot of cars start getting 40/50 MPG the fuel will cost $7/8 a gallon only because the oil companies have fixed costs to cover and if they sell less gasoline they need more profit per gallon.your cost to operate your car will NOT come down it will only go up like everything else.when the goverment starts loosing gas taxes because people use less gasoline do you think they will not rasie the tax on the gasoline to make up for the loss?

So, Dan, are you correcting your boss Bob Lutz?
He said recently we're at the end of the line for improvements in conventional powertrains?
Or did he just say that to influence the decision making for the energy bill?

Again, GM is giving us the tap dance on how wel they are doing. I used to be a huge supporter of the company, but find they are still up to their old tricks.
Why are we, the consumers of America, putting up with the half truths, and their back slapping about how well they are doing on the fuel efficiency and fuel economy aspects of their cars and trucks? The industry itself is taking us for a ride and we just argue over a few MPG. Pathetic!
Meanwhile, in Europe GM is producing good looking, fuel efficient gasoline and diesel because they have to. The European consumer would NEVER put up with vehicles that gets 30 MPG, and neither should we. Why are Americans different than other consumers? I will tell you why, because we are the ober consumer, and the most gullible people on earth. We actually believe the corporate doublespeak on hoe we are special and need to drive huge SUVs and trucks. You would think that the Middle East, Russian, and South American oil is ours by right of birth. It isn't.
Ford GM, Honda and the rest have a very nice stable of automobiles that they can "Americanize" in six months. GM did it with the Aura and the Astra and whaddayaknow? They ain't too bad! But did they bring over the Astra with their nice little diesel? No. How about the Diesel Aura with the bigger diesel? No. But guess who finally is going to bring a new date to the dance? Honda will once again beat the traditional American manufacturers to the fuel efficiency and economy dance when they announce the diesel Accord next summer. What excuse will GM then come out with? Their tired, monotonous tirades about the market driving their decisions is as full of bunk as anything I have heard over the past 10 years. I have given GM plenty of time to get their act together, no more.
Your company deserves no credit for incremental improvements in fuel economy. It seems like voodoo economics has taken root. Its time you spend some of your money on developing some engines or your company wil become another footnote of American history.

You have moved entirely away from a simple to install and control old-school means to not only increase engine hp but mpg at teh same time. I'm referring to supercharging. When a 3800 V6 with s/c can return over 30 mpg highway and 23 combined(real world)in a 3500# car, why have we said "no more s/c for GM" or something to that effect. I've got nothing against V8s for the power I desire in a family sedan, but couldn't an adequate amount of power have been realized from s/c on the 5300 V8 that starts at 303 hp n/a? Heat buildup is minimal with s/c compared to turbos.

While most people posting here haven't a clue about possible development of higher mileage cars, it is still true that GM is NOT THE LEADER in the mileage race,
and it WON'T BE if you stay with the current mentality and pace of improvement.
The only acceptible path is to get a TWO-GENERATION LEAPFROG
on the fundamentals, as opposed to the always-behind-Honda pace this company is always on.
Management has to commit to it, set the goals AND a low price target, tell the engineers to hit it or be fired, and walk away and DO NOT BOTHER THEM UNTIL THEY HAVE THE WORKING PROTOTYPES TO DEMONSTRATE. PERIOD.

Just as MAGNERIDE is not necessarily a superior solution to the ride/handling compromise as compared to fastidious development of conventional
systems on the right road courses(like CTS), even though it costs a HELL OF A LOT MORE, putting empirical-minded advanced engineers/scientists in a skunkworks with a leapfrog improvement goal and a clear deadline, and walking away 'till they have a REAL WORKING ENGINE will yield they same results without having to SPEND BILLIONS in development. Make it so at all costs!!

There is no denying GM has made innovations to help improve fuel economy, but it is ignoring an obvious solution, reducing vehicle weight. Your 2008 Cobalt could match the weight of the 1988 Cavalier if you built it today with plastic body panels and a spaceframe chassis. The plastic panels would reduce vehicle weight by 150 pounds alone.

Your decison makers are short sighted. The Spring Hill and Wilmington plants could build
roughly 425,000 additional units with this type of chassis today, Spring Hill assembly line 1 and 2 sit idle today. Not a wise choice with $3 gas. No other manufacturer could match this volume capacity. Do we really need more trucks,suv and crossovers. How about coupes, your competitors are eating you for lunch in this segment.

How about applying the aluminum spaceframe technology of the Corvette Zo6 to truck and suv applications? The $10,000+ profit margins on these vehicles would justify the expense. Overall vehicle weight could be reduced by something like 500-750 pounds.

Part of GM's problem is not leveraging its strengths, whether it be in marketing or utilizing existing technology. Time to take a look at some resumes?

Let's follow up the Cavalier-Cobalt example. Do we want cars from 2027 to make EXACTLY the same mileage as they do now, but weighting 4,000 pounds and having 300 hp? Come on, this is hardly evolution.
Cars need to be smaller, lighter, using non-fossile fuels. Everything else is not helping the environment.

Instead of spending millions to lobby against fuel economy standards (which done willingly would actually be a marketable selling feature) why don't they spend it on the R&D to be a better company? Let Ford and Chrysler (and Toyota) play games fighting to sell the same old crap while GM actually redirects it's money to building something better, like they already do in Euorope and China where standards already require 35+mpg (China will require 36mpg in 2008). I'd gladly take 1% of the lobbying budget to get you to 35mpg by 2014.

And for the record, I recently rented a Colbalt and was very impressed with the fit, finish, and ride quality. It's a very rigid car with a lot of features. The interior quality is still a little behind most imports, but not by the vast margin it used to be. Ovaerall it was a very good car, the kind that will build a lasting relationship with owners (unlike the cheap and unreliable cars that turned young buyers off the brand a few years ago).

with the govt mandating smaller hi mileage cars GM can start to build them. if they had built them before and the other car companies did not all the customers would have went to the companies that sold the bigger heavier cars because that is what most people in the US want.now it will be a race to see who can build the best hi mileage cars because there will be no big heavy cars from any US manufactures

Daytime running lights waste fuel. Why does GM persist in forcing this unwanted option on those of us who do not want them. I heard that GM disconnects the daytime running lights when cars are tested for the EPA.

If you guys dont jump on this and sew up a contract then I
there is a problem.
At 10 times this LiIon power pack is the answer you have been looking for.

http://www.sciencedaily.com/releases/2007/12/071219103105.htm

CEO Rick Wagoner said, “The new CAFE standards pose a significant technical and economic challenge to the industry. It’s a challenge that GM is prepared to put forth its best effort to meet with an array of engineering, research and development resources.”

Mr Wagoner,

Why will it take an "array of engineering, research and development resources" to solve "...a significant technical and economic challenge," when the cars you sell in Europe are already capable of meeting the new U.S. CAFE standard?

Wouldn't the easy, direct solution be to start selling the same cars here you already make and sell in Europe?

Don't make it more complicated than it is.

V/R

Gary Dikkers

Tyler,

Consider a few of the main issues with engines, efficiency, cost, and emissions. In any combustion engine higher pressures tend to make an engine more fuel efficient, yet they create more NO2 and less CO. So you gain efficiency at the cost of NO2 emissions (oops). Another way to increase efficiency is to raise the operating temperatures. Since cost and weight are issues, engineers are forced to figure out how to use lighteweight, cheap and strong materials (such as iron and aluminum). Contrast this to aircraft turbines which operate at temperatures above 2600 F and their costly materials. The ICE is one of the best ways to make power, the combustion temperatures and pressures instantaneously go to several factors above ambient. This gives ICE's an efficiency level thats not to bad for their cost and weight.

As to all the eggs in one basket. The problem is that there are many types of fuels and its not easy to efficiently run them all. Additionally the total of the alternatives adds up to something usable but no single alternative can deliver the demmand that is currently there. Changing people is probably going to be easier then replacing gasoline/diesel as a fuel source.

As a country it is possible to come up with energy solutions, but I'm sure people will deem them to costly and not environmentally friendly enough.

Motorman,

You are partly correct. I'm pretty sure the price of fuel is currently demmand driven. Companies will sell the same amount of gasoline or other similar fuels. The number of people using that fuel will increase which is what we actually need. And the gov't might have to tax more somewhere else. There is no free lunch as the saying goes, and eventually we have to cut back on our energy usage. We have been increadibly spoiled by cheap energy. It is a luxuary that few generations before have ever had. We have long forgotten that. When was the last time you had to go chop down a tree to heat your home or run your steam powered car? Energy is a luxuary.

Nate the experts say that $20/$25 of the price of a barrel of crude is the speculators running the price up. it works like a commodity

1988 Chevrolet Cavalier: 2.0-liter engine; 90 horsepower; 2,359 pounds; EPA mileage ratings of 22 city and 33 highway.

2008 AVEO5: 1.6 liter engine; 103 horsepower; 2,359 pounds; EPA mileage ratings (automatic) of 23 city and 32 highway.

You finally have some real solutions to the status quo. Why are not all GM engines E85 compatible?
Real extra power with DI that are not available in the US market; the latest Saab stuff that would bring US cars more performance in a smaller DI turbo motor. Holden has designed and built some terrific cars that have never been offered here in a real performance car. G8 Pontiac excluded.

Simply put, I'm not impressed with anything GM's doing now or what they've done since 1970. It's so glaringly apparent when contrasted with their European offerings. Be original. We should be getting 200 miles to the gallon, not the tank.