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natefish 05-14-2010 08:57 PM

The Easy Leg: Vehicle Efficiency
 
Peak Oil Investments I'm Putting My Money On: Part X, Improving Vehicle Efficiency

Quote:

According to Dr. Sperling, in the last twenty-five years, auto manufacturers have made great strides in engine efficiency... but they have used the progress to deliver more power at the same MPG, rather than increasing MPG. Since 1985, average fuel economy has dropped 5%, while vehicle weight has risen 29% and average horsepower has increased 86%. That's what makes vehicle efficiency easy: even without further advances in engine efficiency, we could greatly increase fuel economy by just returning vehicle weight and horsepower to 1985 levels.

In February, our own John Petersen provided a list of technologies for increasing vehicle fuel economy, compiled from a report by Robert W Baird & Co. The table shows nine different technologies, many of which can be combined in a single vehicle which increase vehicle efficiency an average of 12.5%.
Efficiency
Hybrid Electric Technologies Gain
Prius-class strong hybrids with idle elimination, electric-only launch, recuperative braking and acceleration boost. 40%

Insight-class mild hybrids with idle elimination, recuperative braking and acceleration boost. 20%

Engine Technologies
Direct Fuel Injection (with turbocharging or supercharging) delivers higher performance with lower fuel consumption. 11-13%

Integrated Starter/Generator Systems (e.g. stop-start systems) automatically turn the engine on/off when the vehicle is stopped to reduce fuel consumed during idling. 8%

Cylinder Deactivation saves fuel by deactivating cylinders when they are not needed. 7.5%

Turbochargers & Superchargers increase engine power, allowing manufacturers to downsize engines without sacrificing performance or to increase performance without lowering fuel economy. 7.5%

Variable Valve Timing & Lift improve engine efficiency by optimizing the flow of fuel & air into the engine for various engine speeds. 5%

Transmission Technologies
Automated Manual Transmissions combine the efficiency of manual transmissions with the convenience of automatics (gears shift automatically). 7%

Continuously Variable Transmissions have an infinite number of "gears", providing seamless acceleration and improved fuel economy. 6%

The table shows it should be possible to increase fuel economy by the 40% from 2009 levels by 2016, as required by current law using only engine and transmission technologies. Hybrid technology, smaller vehicle size, light weighting, low rolling resistance tires, better aerodynamics, or reducing engine power could each increase efficiency further. Hence, automakers have a wide variety of potential strategies to meet the 2016 targets with existing technology. While this plethora of options is good news for automakers, it is not all good news for investors. With the wide choice of existing options for increasing fuel economy, it's difficult to foresee which technologies will bring the greatest returns to investors. Further, few of these technologies are proprietary to any single publicly traded company.

natefish 05-14-2010 09:01 PM

This article came up at work today. Of course, there were the HP junkies that said nobody who liked cars would ever want to go to 1985 vehicle HP/weight levels.

Of course, I think, in other parts of the world new cars like this exist...unfortunately not here in the USA :-(

autoteach 05-14-2010 10:23 PM

This is what I have been telling my students for the last 5 years! We have increased efficiency drastically, but increased HP to maintain that mpg. The only problem that we have with reducing weight is the required safety equipment. Manufacturers could cut weight in creature comfort items, though, but the rewards of FE would be marred by poor sales.

mcrews 05-15-2010 01:44 AM

have made great strides in engine efficiency... but they have used the progress to deliver more power at the same MPG, rather than increasing MPG. Since 1985, average fuel economy has dropped 5%, while vehicle weight has risen 29% and average horsepower has increased 86%. That's what makes vehicle efficiency easy: even without further advances in engine efficiency, we could greatly increase fuel economy by just returning vehicle weight and horsepower to 1985 levels.

On so many levels this is a classic example of percentages telling a different story than the facts that exist.
But I don't want to get into a huge discussion.
let me just offer up two thoughts:
1. CAFE standards set different goals for trucks so the manufacturers moved to the more obvious choice and built trucks. Kinda the unintended result of government and lobby intervention.
2. I drive an 02 Infiniti Q45. The Q was introduced in 1990 and never caught on like it's competition the Lexus LS. So in late 2000, Infiniti decided to take one last bite at the upper end luxo/sport sedan market. The 2002 infiniti weighs almost 500 lbs less than the 4 other sedans that it competed with. lot's of aluminum and alloy. It also got 50 more hp than the next competitor. THey all run 4 to 4.5 liter V8s. The Q also got better mpg than all four. (not a big selling point in this bracket of vehicles)
Without any major mods or hypermiling, I was getting 27mpg on 300 mile trips (epa 23)

my point is that manufacturers can produce cars that are effecient and perform better.

as a final thought, I am perplexed by the reference to 1985 numbers.... The mid 80's were a horrible time for cars. Pollution devices were being strapped on with little engineering and thought. that was probably the low point for effecency in american cars.
There was no effecency in the use of materials either.

natefish 05-15-2010 08:45 AM

Quote:

Originally Posted by mcrews (Post 174638)
But I don't want to get into a huge discussion.

What!? Doubt that's even possible with this group! ;)

Quote:

Originally Posted by mcrews (Post 174638)
The 2002 infiniti weighs almost 500 lbs less than the 4 other sedans that it competed with. lot's of aluminum and alloy. It also got 50 more hp than the next competitor. THey all run 4 to 4.5 liter V8s. The Q also got better mpg than all four. (not a big selling point in this bracket of vehicles)
Without any major mods or hypermiling, I was getting 27mpg on 300 mile trips (epa 23)

my point is that manufacturers can produce cars that are effecient and perform better.

That's a good point, less HP doesn't always equate to better efficiency, but I think in general, a smaller, well built engine would help with better mpg.

Quote:

Originally Posted by mcrews (Post 174638)
as a final thought, I am perplexed by the reference to 1985 numbers.... The mid 80's were a horrible time for cars. Pollution devices were being strapped on with little engineering and thought. that was probably the low point for effecency in american cars.
There was no effecency in the use of materials either.

I think 1985 was used because it was the peak of average MPG for vehicles. But I'm not sure. If that's the case, it still leaves lots of room for questions like: What vehicles does that figure include? It could be that cars are more efficient, but people are driving more trucks and SUVs so the overall figure is down.

RobertSmalls 05-15-2010 09:56 AM

I think a gas/electric hybrid is a good solution for most middle of the road consumers who want good acceleration and good fuel economy. As the electric portion of the hybrid gets more powerful, city mpg and acceleration get better. As the gas portion gets smaller, highway economy improves.

Going hybrid may add 100-200lbs to the car, but it more than pulls its weight as you can see from the EPA city numbers. It also adds thousands of dollars to the price of the car, and we won't see hybrids become the norm until automakers have exhausted all the cheaper methods of buying MPG, some of which are also on the list in the OP.

jamesqf 05-15-2010 11:56 AM

Quote:

Originally Posted by mcrews (Post 174638)
The mid 80's were a horrible time for cars. Pollution devices were being strapped on with little engineering and thought. that was probably the low point for effecency in american cars.

'85 Honda CRX. 40+ mpg even the way I drove it. And pretty darned close to a perfect car for me & my lifestyle: two seats, plus room for backpacks, skis, bikes (with a little creative fitting), and just about anything else that came along.

Build the same thing today, with fuel injection & turbocharging, and maybe some aluminum & carbon fiber in the body, and I'll buy it.

cfg83 05-15-2010 11:58 AM

autoteach -

Quote:

Originally Posted by autoteach (Post 174619)
This is what I have been telling my students for the last 5 years! We have increased efficiency drastically, but increased HP to maintain that mpg. The only problem that we have with reducing weight is the required safety equipment. Manufacturers could cut weight in creature comfort items, though, but the rewards of FE would be marred by poor sales.

I would compromise. Keep the safety in, which assumes(?) a ~29% gain in weight on average, but offer lower HP engines, aka engines that represent a ~29% gain instead of an ~86% gain (as the original article states).

CarloSW2

mcrews 05-15-2010 02:25 PM

But my point is that the 85 engines were not optimally effecient. That is the problem with the whole article.
85 was not some magical moment in mpg nervana.

I will agree that 2 cars come to mind as first steps but the rest of the industry was still behind the curve.
1. is the honda crx
2 corevette

what is intesting is both of these cars were as light as possible and were FAST.
Key words: Light and fast. as a byproduct, the also got good mpg.

The article is take a broad swipe at numbers that include everything from crx to Ford F-350 dually trucks.

As we have seen in the last year, auto manufacturers in america were not really making cars. The were making items with overinflated prices to fund 'unfunded' pensions and healthcare for retirees.
Much like Greece and soon California and the US, the product was irrelevant. It was just away to redistribute wealth.
The only reason car companies can't build little fun eco cars is because there is not enough margin to cover the add-on costs.

It becomes frustrating when people complain about 'the good old days' and have no grasp what so ever on the outside forces that cause things to happen.

When I was in college from 76-81 I said that if unions REALLY believed that their members built quality products then they should get stock options instead of additional benefits. Guess the unions were smarter than me........

Piwoslaw 05-15-2010 03:01 PM

Quote:

Originally Posted by cfg83 (Post 174692)
autoteach -

I would compromise. Keep the safety in, which assumes(?) a ~29% gain in weight on average, but offer lower HP engines, aka engines that represent a ~29% gain instead of an ~86% gain (as the original article states).

But wouldn't a lighter car also have lighter safety equipment?
Take a 2000kg luxury car, pull out the electric/electronic gizmos and you save 200-400 kg. Another 100-200kg can be saved by replacing the 3.5 liter V6 with a turbocharged, aluminum block, 100hp 4-banger, and the auto trans with a manual. By now, the crumple zones have to handle 30% less momentum in a crash than in the original car, so they don't have to be so buffed up. And what about making the whole chassis out of aluminum (like the Audi A2)?

Of course, things like airbags still must be present, and I don't know whether their weight can be reduced.


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