The Center for Automotive Research (CAR) contends that as fuel efficiency rises to very high levels, the benefit to the customer shrinks. At $5 per gallon, for example, a 15,000-mile-a-year driver can save $3,750 on gasoline annually by jumping from 10mpg to 20mpg. But by going from 40mpg to 50mpg, the savings drop to only $375 annually, the curve shows. As consumers reach those limits, CAR says they are likely to keep their current vehicles longer, a phenomenon it refers to as the "Cuban-ization" of the American auto market. (Source: Center for Automotive Research)
I agree Charles, smaller turbo charged engines are a good small incremental efficiency gain by engine downsizing. Doubling MPG, would require a 100% efficiency gain by the drive train, if car mass/size is held constant. With a good gasoline engine already around/above 35%, that would require 70% if done with the engine alone ... well above the 58% thermal efficiency limit of a perfect loss free Otto engine. Where do we get the rest of the 100% gain without downsizing cars and trucks?
Active Fuel Management becomes less important with a smaller turbocharged engine, because the throttle will already be well off idle at road speeds, a diminishing returns problem when trying to combine both enhancements on the same engine. http://en.wikipedia.org/wiki/Active_Fuel_Management
From http://en.wikipedia.org/wiki/Turbocharger "Only 10 percent of light vehicles sold in the US are equipped with turbochargers, making the United States an emerging market, compared to 50 percent of vehicles in Europe that are turbo diesel and 27 percent that are gasoline boosted."
55mpg for a small passanger saloon? Easy. 1.2 ~ 1.5 turbocharged diesel engine. It's happening now in Europe. Take a look at the figures for EU market Volkswagen Jetta and Polo, Seat Octavia and Fabia, Citroen C3 etc.
I have no sympathy for the car companies. Clean diesels are incredibly efficient. An intercooled turbocharged diesel hybrid would blow these standards easily. And the technology is OLD technology. Sure cars will have to be smaller. We need to change the road infrastructure to get the small mass cars away from huge semis,etc. I drive an MB 190D that gets 35mpg on a gallon of home brewed biodiesel. In Europe you can get diesels that do exceed these 54.5 mpg standards.
On another point, get govt out of regulating things they don't understand. Diesels are currently regulated on particulate matter and they put those stupid post combustion units on them making them lose up to 30% of their fuel efficiency. All because some idiot didn't bother to think that what's really important is pollution per mile driven.
Increased infrastructure for bicycles and e-bikes would get many out of their cars and save so much money that we wouldn't have as much need for this kind of silliness from the government.
If it is desired by consumers, then it does not require a government mandate.
Example: both Ford and GM have benched programs for new hybrid truck platforms, citing that solutions are technically and financially unattractive. A government mandate pushes them to build the unattractive solution anyway.
Some will say that this encourages Ford and GM to innovate. Yes, they must devote resources to develop a solution that competes against other companies forced to release unattractive solutions. At the very least, this diverts resources away from development that is attractive and desired by consumers.
Rather than a marketplace that reflects the cumulative values of consumers, we end up with a command economy. Engineers love a technical challenge, but step back further and realize that this is a liberty challenge.
When comparing U.S. mileage vs. Canada and the UK, you have to consider they use Imperial gallons, whch have more gas per gallon and will show a higher MPG. Oil consumption is already down in this country, we're shipping oil overseas, and gas prices are still very high. Will the consumer really see a reduction? More oil will be sent to China and other developing countries that have air pollution issues. Will air quality improve in those countries as we presumably make our air cleaner? As fewer gallons are used in the U.S. gas taxes (revenue) per gallon will be reduced to the government. They won't like this, so taxes will increase, or we will pay a road use tax based on miles driven annually. This, added to the increased cost of vehicles, will probably mean that people will keep their 30mpg vehicles longer. This will affect auto manufacturing and therefore jobs. Increased unemployment. Another government idea not thought through, or if it was, making a good sound bite and playing on our ignorance.
I've been asking this question since the 1st hybrids rolled off
the assembly line...........Why doesn't anyone make a hybrid diesel? Cummins already has one of the CLEANEST running diesels on the market. They even have been able to avoid the urea injection in vehicles line the Dodge Ram. They have a 4cyl version of their popular inline 6 cylinder. Their 6.7L could have a 4.5L sibling mated to a hybrid system that makes almost as much torque as the 6cyl and would get WAY over 30mpg on the highway in a FULL SIZE truck. A 3/4ton Ram could really play double duty as a daily commuter, a work truck, and a weekend warrior.
Then an even smaller version could be put in a half ton truck with highway mileage near 40mpg.
Then cars like the Diesel Jetta that already get 40mpg could be getting 50 to 60 mpg! Even better, the addition of a hybrid system to a diesel would get the performance of these diesels up there with the gas engines. It's a win win for everybody.
Like the article points out, this would probably add $8,000.00 to the price tag. A diesel jetta already cost $4,000 more than a 2.5L 5cyl gas version. A Hybrid Civic cost about $3000.00 more than the same non-hybrid. Mating the diesel to the hybrid should be a no brainer.
In the caption of the graph, it says: "But by going from 40mpg to 50mpg, the savings drop to only $375 annually..." I just have to say, very few cars currently get 40mpg. I have a one year old relatively efficient car, on an all-highway long trip if I'm really lucky I can actually get 35mpg. But in regular driving with traffic lights and traffic jams, I often don't even get 25mpg. The only cars that reliably get 40mpg in normal driving now are hybrids or range-extended electric vehicles. So citing 40 to 50mpg change, when I will see 25 to 50mpg change, seems a bit disingenuous.
This requirement will put more hybrids and electric vehicles (possibly range extended) on the road, more than tiny unsafe gas powered cars. If due to economies of scale it makes the price of a future Volt come down from $40K to under $30K, that would be great.
Volkswagen turbo diesels? Look at their reliability before flaunting them as a solution! Consumers won't accept a car engine that only lasts 80,000 miles before requiring a rebuild that costs thousands of dollars. See, e.g., Consumer Reports for reliability records.
What if we let engineers build what the people want? People on this board have pointed out a number of examples where mandates have warped the market to the point where good, desirable solutions are outlawed. If you took off the chains and people flocked to buy gas guzzlers, well gas isn't that expensive, is it? Maybe safety is worth the extra money to some people?
I've got a cheap government mandate solution for you all that will improve efficiency and save tankers of fuel a day: GPS speed governors. Try getting that one through Congress.
Isn't it ironic that the same greener-than-thou types who work tirelessly to get your Hummer legislated out of existence are the same ones bombing down the highway doing 80 in their Pry-Us--late for yoga class, again!
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