Monday, May 01, 2006

Efficient fuel usage

American vehicles account for a tenth of the world's daily oil consumption. But even with a 17% year-over-year rise in the price of gasoline, consumption continues to grow:
In the first quarter, the real price of gasoline averaged about 17% more than a year earlier, and U.S. gasoline consumption was up just 0.3% -- fairly close to flat.
Historically, domestic gas consumption grows at about 1.5% annually. That consumption has only been reduced by 1.2% of the expected amount assuming only an inflationary price increase yields an elasticity of less than .1. Part of this stems from driving necessity. It also comes from the fact that, as psychologically painful as the gas price may be to the average consumer, it represents a small fraction of personal-consumption spending--only about 3%. On a micro level, gasoline costs are just a nuisance. But if prices rise to four or five bucks a gallon, and a couple more percentage points of discretionary income are diverted to fuel purchases, it will likely begin shaving off a couple of percentage points of GDP growth.

While enterprising entrepreneurs are taking big risks that we all stand to benefit enormously from, there are several things that can be done in the name of gasoline parsimony that require very minimal lifestyle changes:

-If able, keep your windows up and blast the vent. Failing that, drive with the windows down in the city and suburbs. Use air conditioning on the highway. The AC lowers fuel economy by about 10% irrespective of speed. Drag from downed windows decrases fuel economy by about 10% when you hit 45 mph. At 55 mph fuel economy plummets 20% or more.

-Watch the RPM. Keeping it under 2,000 when accelerating saves a substantial amount of fuel. Doing so nets me sixty miles more a tank (I drive a V-6 '97 Taurus). Yes, people will on occasion ride your tail as they honk and gesticulate wildly, but that makes the strategy all the more satisfying.

-If you drive an automatic, ease the accelerator a bit as you build speed. This will cause the auto transmission to upshift earlier than it would otherwise.

-Cruise the freeway as slowly as is affordable. Dropping from 65 mph from 75 mph reduces fuel costs 13%, and going from 65 mph to 55 mph saves another 12%.

-Keep your tires inflated to the upper limit of the recommended PSI range.

-Fill up in the early morning or at night and on cooler days during the week. It'll cut down on gas evaporation.

-City planners: Start with an understanding that every time the light changes at an intersection, deadweight loss is created, because there must be an interregnum in which the signals for all directions must be red. Minimize the number of signal changes. From this, realize that having a commuter wait five minutes at one light and then cruise through the rest of the intersections on his drive in is exponentially more fuel efficient than having him wait thirty seconds each at ten different lights. Create an almost perpetual green along main thoroughfares. Drivers will have to wait a few minutes to come from the rivulet onto the major road, but after that it's quasi-highway.

-Install countdown systems in all electronic crosswalk signal devices. This serves as an enduring yellow light that will increase traffic flow and save fuel.

-Drastically increase drunk driving punitions. I rode my bike twenty miles roundtrip to and from work for almost two years. Then a couple of years ago I was hit from behind by a car, driven by an inebriate with a blood alcohol level of .24, that knocked me within inches of my life. Now I burn a gallon of gas every weekday.

(Personal use)


adog said...

You are a lucky dog. How long's that been now?

crush41 said...

Four years next April.