George Iliff
Since 1985, automobile manufacturers have been required to meet a CAFE (Corporate Average Fuel Economy) of 27.5 miles per gallon. Several years ago, legislation was introduced in Congress to raise the CAFE to 40 mpg. So far, the legislation has not been passed but it does have the attention of the environmentalists including the Sierra Club and the issue will continue to be raised from time to time.
Discussions on this issue have been intense but very shallow. The environmentalists see this as an obviously good idea which is only being resisted because of corporate greed and a reluctance to expend the engineering effort. The manufacturers have been working behind the scenes to prevent passage of this legislation and saying relatively little publicly.
The problem facing the automakers is that the subject is just too complicated and boring to explain to the general public. I will attempt to provide this explanation and hope that at least a few of you Mensan's will bother to read the article.
Following the Arab oil embargo of 1973-74, Congress began to require manufacturers to produce cars that were more fuel efficient. As a result, the CAFE rose from roughly 14 to the present 27.5 in only 10 years and that was great! But that doesn't mean that it will be that easy to go further in raising the CAFE.
The increase in fuel economy came from such items as (1) use of radial tires, (2) more extensive use of computerized fuel injection, (3) replacement of steel parts with lighter material such as aluminum or plastic, (4) somewhat lower wind resistance, and (5) generally reducing the size and weight of cars. The first problem then is that these tricks fall into the "one time only" category and cannot be used again. The point is that the first jump to 27.5 was easy but it will be really hard from here on up.
Some incredible mpg figures are possible by very small cars such as the Geo Metro which represent about the limit in downsizing. Such cars have been used to improve the manufacturers CAFE's. The bottom line is that any significant improvement in CAFE from here on out will have to come from producing such very small cars. Now, I happen to like little cars but will the public overall be willing to use nothing but motorized roller skates?
Another significant point is the composite effect of melding various models of cars which have different mpg levels. For example, suppose General Motors produced half Geo Metro's at 60 mpg and half Cadillacs at 20 mpg. So we have a CAFE of 40? Well maybe that would qualify but we would be fooling ourselves. Lets say we send out one Geo and one Cadillac for a 60 mile drive. The Geo would use one gallon. The Caddy would use three gallons. Total use: four gallons to cover 120 miles of driving. That results in an average fuel economy of only 30 mpg!
I repeat, to significantly raise the true CAFE, we ALL will have to drive Geo Metro's.
Yet another point is the question of diminishing returns. For every 10 gallons of gas used in 1974 at 14mpg, we now only use approximately 5 gallons. Now, lets go to the full 40 CAFE - and we only will use 3.5 gallons of gas. Lets see now, going from 14 to 27.5 using the relatively simple tricks described above saved 5 gallons of gas. However, the very difficult jump on up to 40 only saves only another 1.5 gallons of gas. Interesting!?!?!
Some day, the world will run out of petroleum reserves and this will have a disastrous effect on every one. Thus, the concern with saving our reserves does deserve attention. This attention should cover not just automobiles, but rather, all sources and uses of energy and possible conservation measures including mass transit, better insulation, etc., etc. An overall plan is required.
As for automobiles themselves, the best solution overall is to rely on economics. If we are using too much gas, just raise the price of gas. People will then either drive less or buy Geo Metro's or both. The rest of the world charges $3 or $4 per gallon. Maybe they know what they are doing.