It is worth including that cars get driven more early in their lives so that you should see a closer approach to 40 mpg near Year 10.

CAFE can help, but there is much more to be done including driving less, shifting freight to rail, and starting to use PEVs and gas powered cars which don't even have mpg ratings.

In terms of costs, these necessary changes cost the same if we do them now or later because we replace cars and trucks anyway. But, for fuel, waiting until fuel is mainly supplied from expensive sources means that we can not take advantage of our market leverage to cut the price of oil and make our transformation using cheap oil. So, delay is expensive.

At this point, just about any new source of oil transforms our energy gathering system from efficeint to inefficient and this is the basic reason why conservation of our efficient sources makes much more sense than trying to suppliment with new supplies.

Chris

Chris,

True about milage on old vs new cars. If you want to include it, you need to grow the model in other ways. The short form above assumed 100% replacement with a 40mpgf vehicle.

Does a reasonable law mandate 40mpg from day one? There is only one mass produced automobile for sale in the US that meets that goal today. How long would it take Toyota to gear up for the volume? ow long would it take for competition to react?

Does a reasonable law force older vehicles to be retired? e.g. Can you force a 1995 Ford Taurus with 100k miles off of the road? What happens to the value of that vehicle if equivalents (size, comfort, ability to pull small trailer, style) are legal to own but no longer legal to produce?

There are quite a few cars for sale outside the US which do well on fuel efficiency so one might be able to phase in the standard fairly quickly.

Where I live, older vehicles that can no longer pass their emissions tests and are too expensive to fix get junked though there are some exceptions. In some sense, that forces older cars off the road.

Again, CAFE can help, but our basic problem is a fuel shortage and we need to address that with imediate conservation since it is quite clear that market forces cannot alleviate the shortage, only ration by price. The considered drill won't do anything really to help considering general depletion. In shortage situations, we use our rationing plan and that is what will drive our conservation effort. It also assures us that we will have the money available to buy efficient cars that can re-exend our range of mobility.

Chris

Hi Name,
This is an important issue, as improving vehicle mpg is going to be one of the major drivers of reducing oil consumption. The article posted by Stuart Staniford at TOD on 11th Feb, 2007 examines this in detail.
You are correct that we cannot immediately improve the CAFE standards, but last year as well as the 7million passenger vehicles(average 27mpg) there were 7million light trucks and SUV's sold in US, having an average of 22mpg. Fuel efficiency for ALL new vehicles could be raised by phasing out the lowest fuel economy vehicles, AND raising CAFE standards for ALL vehicles in a progressive, but more aggressive manner than currently proposed . The US has one of the poorest fuel economy fleets. High fuel prices cause people to use low mpg vehicles less (since the average household has 2.2 vehicles some options are available for many households).
New vehicles 6 years old or less, are responsible for 50% all ALL VMT, so a rapid improvement in fleet average mpg will give much bigger savings than you projected above.

The argument that if there is a recession, less vehicles will be sold,so can't have much effect on efficiency doesn't hold up, since in the 1978-82 recession US average fuel consumption for VMT decreased, due partly to a very big increase( for the next decade) in new vehicle efficiency.

In terms of costs, these necessary changes cost the same if we do them now or later because we replace cars and trucks anyway.

If only that were true. In the real world there are serious delays caused by the fact that (for the most part) the research and development, followed by large scale investment in manufacturing capability, and the creation of a support network for repairs, has not been made. If we assume we are already in a PO predicament, the fact that meaningful preparations were not made ahead of time precludes a timely response. Rushing of (nearly) untested products into production at a very high scale, is associated with some serious costs. I'm not saying we shouldn't try to do that, just that a lot of costly technical glitches should be expected.

I would agree except that the timescale given is 15 years so nothing needs to be rushed. Introduce PEHVs in 2010 as planned and off we go. I don't know if you remember the MVP prizes for the World Series last year. A couple of hybrids. There is much that is already on the road getting miles logged and final kinks worked out. All we really need is the leadership to say that we won't stand for high gas prices and we'll stop using oil before we'll ruin our economy following that blind alley.

Fifteen years is a short time for Exxon to switch to only selling lubricants in the US, so there will be some resistance. The current drill everywhere stuff is a sign of desperation though. If we leave open the option to export some oil, there may be an accomodation that will be partly satisfactory.

Chris