54.5mpg (number translates to 45mpg EPA) is alraedy here! I drive a Prius that gets 51/48 EPA. It cost $24000, which well bellow the average (the average price for a new car in the US this year is $33,303 acording to Forbes). I can go over 600 miles on a 12 gallon tank of gasoline. It caries 4-5 people with lugage, bikes and kayaks.
I've driven small cars since I started buying cars in 1976, often taking abuse from drivers of larger cars and trucks. Efficiency has always mattered to me. Prices of gas are relative to where you live, as are most things. If you live in Toronto or another large Canadian city, I understand that real estate has gone up about 80% in the last 10 years. I don't know if Canadian wages have kept pace, but my point was/is that most people vote with their wallet, and will keep an older vehicle with fairly good mileage vs buying a new expensive, probably same size, vehicle just to save a few cents at the pump and be "greener". And as I stated, taxes for highways or whatever that are collected by the government will also go up as revenue goes down with fewer gallons used. Especially now, people will look out for their own best interests. Don't forget that most consumables are delivered at some point by truck. If fuel prices go up, so do the price of those items. I can't speak for U.S. suburbia, but in the rural U.S. there are many places where trucks are used as trucks should be used.
I own a 2007 Toyota Prius that has been averaging 56.5 MPG on my daily commute to work for the last 5 years. In cold weather it gets about 52 MPG, in the summer about 60 MPG. Of course I drive it very conservatively. (When my wife, she of the lead foot, drives it the mileage is considerably less)
It cost $24,000 including tax and license when I bought it. I calculated that the extra $10K I paid over the cost of a Ford Focus (getting 35 MPG) would not be recouped over the life of the vehicle even with $5 per gallon gasoline. That being said, I am still glad that I bought the Prius instead of the Focus.
The point I am trying to make is that it is possible to profitably build commuter cars today that meet the requirement. Getting customers to accept the cost tradeoff is a problem though.
Auto manufacturers do not sell vehicles in the same ratios that are used to compute CAFE. The 54.5 CAFE target will result in a real fleet economy of approximately 40 MPG, if it is achieved. There are a few vehicles available now that get 40 MPG, but most people do not want them. The government can not tell people what to buy. Market forces are much better at doing that, which is why high MPG vehicles are more popular in Europe where fuel is taxed at much higher rates. That will not work in the USA where a politician who suggests such a high tax rate will be railroaded out of office. The biggest air polution problems are in densely populated areas, which also have the wealthiest consumers who can can afford to drive what they want. There is a solution to all of this, but it will not happen by government mandate. The auto industry is already making great strides to reduce vehicle weight and to develop more power from smaller engines. This does not require exotic materials, but evolutionary improvements to metal alloys and plastics that enable less material to do the job. Many alternatives to the standard reciprocating internal combustion engine have been proposed, but are not likely to take over the automobile market. Steady improvements to engine control algorythms and variable valve timing are helping. Gasoline is already being blended with natural gas liquids when it makes economic sense, so it is not necessary to run on pure natural gas. Engine start-stop, downhill coasting, passive hybrid operation and regenerative braking will become commonplace because they can be implemented inexpensively. Body designs are becoming more aerodynamic, but they don't have to look like needles. Computer modeling and wind tunnel testing can achieve acceptable results without warping the interior volume into an unusable shape. Fuel economy is an engineering problem that will only be solved by engineers. The government stance needs to be proactive, not coercive.
Gas prices are high ? Where I live petrol, as it is known, costs $2 a liter, thats about 8$ a gallon (US or imperial?). Gasp. So we drive smaller cars, 1.6 liter engine Corolla or Focus is car enough for anyone. The trend is towards smaller cars. If I lived in the US, I wouldn't buy a larger car, I'd enjoy the savings from paying less for fuel. US rural and suburbia citizens might have ot give up he idea of driving around in trucks.
In 1982 a VW Jetta diesel weighed much less than 2500 pounds and did not have six to eight airbags, and other mandates that now make it weigh over 3200 pounds. It's a wonder that it still gets the high mileage it does. Aerodynamics and other engineering advances surely have helped. To the matter of trucks meeting the standard. Due to truck aerodynamics and the need for heavier frames rather than unibodies on most trucks, so they can haul, etc. without extensive and expensive new technologies, the MPG goal will not be met. Diesel engines help with torque and MPG but you pay a premium for diesel fuel, often offsetting the mileage advantage of gas vs diesel. Hybrids typically boost city MPG the most (read the sticker) because electric motors have near instantaneous torque but may not be much help on a diesel driven on the highway at a constant speed.
Give me a break. I'm trying to get an 8 year old vehicle fixed to be smog-legal NOW and there isn't a CARB-approved (for California) catalytic converter available from ANYONE, so instead of replacing a $70 converter I'm stuck shelling out $900 for a whole new exhaust system, and THAT isn't even critical to fixing the vehicle's problems! (And it's getting where I have a hard time remembering how many years ago I was last offered a job to make some money to help pay for all this but I know it's well over 5.) What would this be like weith a 54.5 MPG vehicle, I don't even want to think! I want to make a point of reminding everyone that this isn't an oversight by our government, the current administration is so extreme that unless you belong to a public sector union or you're an illegal alien looking to not just stay in the country but join a profession (like become a lawyer) or you're in a gay couple trying to get married or you're a young woman trying to get government-provided birth control, YOU'RE labeled a radical extremist and your needs and rights WILL BE TRAMPLED AND IGNORED, as will the US Constitution and everything else you THOUGHT you could count on. Is this out of place for this topic? I don't think so, how will we ever pay for this or any of the other "unfunded gonernment mandates" with no job and no income except handouts from the govt? Tell them to quit trying to "engineer utopia" and try going back to making markets that work foir a change - or is that too radical an idea?
To your point. I drive a 1994 Geo Metro that gets 40-45 MPG. I have people waiting for me when I come out of the grocery store asking to buy my car. California, on the other hand, penalizes me for keeping this car through increasing annual registration fees and punitive smog checks. The state sends me a letter every year encouraging me to sell my Geo to them so they can get this "old" car off the road. My pollution per mile with my little 1 liter engine is miniscule compared to my neighbors Escalade.
Suzuki could sell these things like hotcakes at today's fuel prices, no R&D at all. Just restart a mothballed line. So why don't they do it. The consumer demand is certainly there.
Recall that a Volkswagan Jetta (diesel) has been recorded to routinely achive 50 MPG in 1982. Also recall that putting a spacecraft on the moon was done in less than the prescribed 12 year roll-out time. This 55 MPG objective is niether ambitious or technologically challenging. The reluctance to get on with it is mind boggling. I have to wonder if the oil companies are involved with influencing the holding back of progress.
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