By A.K. Dugan, Lebanon Express writer | Posted: Wednesday, July 30, 2008 12:00 am
If you want to improve your fuel economy - even though gas prices are coming down a little - your best bet is to review your driving habits, consider the conditions you drive in and make sure you're maintaining your vehicle in top condition.
Those aren't the only factors that affect what kind of miles per gallon (mpg) your car gets, but they're at the top of most advice lists.
According to the Environmental Protection Agency (EPA), eliminating jack-rabbit starts and slamming on the brakes can improve your fuel economy up to 33 percent on the highway and 5 percent in town. Other ways to improve your mpg include driving slower to decrease wind resistance, using air conditioning less and making fewer short trips. Lowering your highway speed may improve your mpg up to 25 percent.
Also pay attention to driving conditions. For example, extreme temperatures can lower fuel economy up to 13 percent, traffic congestion up to 15 percent and poor road conditions - gravel, curves, slush, snow, etc. - can reduce fuel economy up to 50 percent, according to the EPA.
Mechanically, making sure your wheels are aligned may better your fuel economy up to 10 percent.
By changing driving habits and doing better maintenance, even the owner of a large SUV can save money, said Dave Abresch, a partner in Primasing motors.
We demand safety, size, power and quiet
Keith Naughton, who has covered the auto industry for more than two decades, said recently on the Newsweek website that Americans have traded fuel efficiency for vehicles that are larger, more powerful, safer and quieter.
Manufacturers build the vehicles consumers want, said Dave Carlson, AAA director of public and government affairs for Idaho. In the 1970s, vehicles such as the Pinto, Chevette and Gremlin could give you pretty good mileage. Then manufacturers found in surveys that safety was clearly identified as a priority, he said, and SUVs were developed.
According to the Environmental Protection Agency website, fuel economy in the U.S. today is at its lowest point in 20 years. At the same time, crude oil costs are higher and vehicle miles traveled in the U.S. have risen four times more than the population has in the same period.
Coming out of the Arab oil embargo and gas shortages of the early 1970s, the U.S. government set up mandated fuel economy standards for vehicle manufacturers. As a result, cars in the 1980s got better mpg than those we buy today. Then came consumer demands that led to steel safety cages, airbags, more soundproofing and other similar features.
In 1975, Congress passed the Energy Conservation and Policy Act, which established standards for the average fuel economy, or MPG, of a manufacturer's fleet of vehicles under a certain weight limit, which was 6,000 pounds initially and was raised to 8,500 pounds in 1980.
The Corporate Average Fuel Economy, or CAFE, program is administered by the National Highway Traffic Safety Administration. The standards rose from 18 mpg for two-wheel drive passenger cars in 1978 to 27.5 mpg for 1985 and after. Two-wheel drive light trucks started at 15.8 mpg in 1979 and went Congress revised CAFE standards in December 2007 to take effect in 2011. The new standards will cover vehicles weighing up to 10,000 pounds and call for increasing average fleet mpg to 35 by 2020.
According to the NHTSA website, "without CAFE, highway fuel use might be 35 percent higher than it is today." But CAFE hasn't cut the U.S. dependency on gas and other petroleum fuels. In 1979, highway transportation petroleum consumption was 121 billion gallons a year; in 1999 it had grown to 155 billion gallons per year, an increase of 28 percent.
Carlson said safety has fallen behind the economy now as the most significant issue for consumers.
Fuel content
American's demand for big, safe vehicles isn't the only reason mileage isn't what it could be.
The content of the fuel is a factor also. The energy content (BTU or British Thermal Unit, a standard means of measuring energy output) of gas varies depending on what's in it.
According to the U.S. Environmental Protection Agency, different formulas are used for summer gas than for winter gas, with the summer formula providing about 1.7 percent more energy. Variations between batches and from station to station may be as much as 3.4 percent in the summer and 4.8 percent in the winter.
Gasohol, also called E10, is a mixture of 10 percent ethanol and 90 percent gas that can be used in all gasoline vehicles.
A new law in Oregon mandated a ten-percent ethanol blend, known as E10, effective Jan. 15, 2008, in northwest Oregon and on April 15 in other western Oregon counties. The law goes into effect in the rest of the state by Sept. 16.
According to Salem-News.com, E10 has been used for some time in the Portland area during winter months without causing major problems.
But E10 is not popular with everyone, in Oregon and elsewhere. It doesn't work in power tools and boats and it causes gas mileage to go down 3 to 4 percent.
The 1990 Clean Act Act Amendments requires the use of reformulated gasoline (RFG) in 17 areas around the U.S. with severe air quality problems. RFG must have at least 2 percent oxygen by weight. It can cause a decrease of 1 to 3 percent in mpg. Oxygenated gas reduces air pollution because it burns cleaner and more efficiently, but it costs four to eight cents per gallon more than conventional gas.
The EPA also has taken steps to reduce sulfur levels in gas and diesel fuel through its national Tier 2 emission standards, implemented with 2004 vehicles. The effect is cleaner air (77 percent to 95 percent cleaner compare to 2003 cars) and fewer respiratory problems for tens of thousands of people but costs about two cents per gallon.
EPA changed how it figures mpg
Fuel economy may appear to be down if the EPA's 2008 mpg rates are compared to previous years. The EPA revised the way they calculate mpg for 2008 vehicles to show the effect of drivers' faster speeds and acceleration, air conditioner use and colder outside temperatures.
AAA's Carlson said the EPA's new way of figuring mpg is more realistic for the way people drive.
For example, a 2007 Ford Taurus (automatic, 4-speed, 6 cylinders, 3 liters, regular gas) is listed by the EPA under the new systems with 18 mpg city and 25 mpg highway. Under the old system, the same car would have had 20 mpg city and 27 mpg highway.
A Honda Accord (automatic 5-speed, 6 cylinders, 3 liters, regular gas), under the new system is listed for 18 mpg city and 26 mpg highway and under the old system for 20 mpg city and 29 mpg highway.
At the EPA's www.fueleconomy.gov website, gas mileage may be compared for vehicles made since 1985.
Buying a more fuel efficient vehicle
In an article entitled "Comparing mileage: Not all mpg's are created equal," Consumer Reports advises that small changes in fuel economy may be more significant in a fuel-inefficient car than one that is efficient. The article cites a study at Duke University Fuqua School of Business that compares changes from a Chevrolet Tahoe and a Toyota Camry to more efficient vehicles of about the same type. Trading in the Camry for a Honda Civic Hybrid yields a 13 mpg improvement and savings of $700 in gas over a year. Replacing the Tahoe with a Toyota Highlander, which seats seven, results in only a 4 mpg improvement, but savings over a year of $762 in gas.
Consumer Reports recommends looking at the whole cost of a vehicle, not just fuel economy, when making decisions about buying one.
Abresch agreed.
"Look at the whole picture; look at gallons per year or gallons per mile rather than mpg. I think you're going to make a better decision," he said.
Carlson said for people who are stuck with the vehicle they have, the best way to spend less on fuel is to drive less.