tigerhonaker
05-16-2006, 08:00 PM
Fuel economy stickers mislead car buyers:
EPA has proposed more accurate testing, but for now,
consumers can't rely on gas mileage ratings:
Mike Maharry
Idaho Statesman
The Idaho Statesman | Edition Date: 05-16-2006
As Treasure Valley gasoline prices climb toward $3 a gallon, more new-car buyers are checking the mileage stickers as they shop.
But for at least another year and a half, the numbers calculated by the U.S. Environmental Protection Agency won't give people a true picture of the mileage they can expect from a new car.
Research by various nongovernment agencies show the EPA numbers are grossly inflated — in come cases by as much as 30 to 50 percent.
According to fuel economy tests conducted by Consumer Reports, the four-wheel-drive Jeep Liberty Diesel Ltd., with an EPA city rating of 22 miles per gallon, got only 11 mpg when tested by the magazine.
The hybrid Honda Civic Sedan tested at 26 mpg in city driving, 46 percent below the official EPA rating of 48 mpg.
A large sedan, the Chrysler 300C, had an EPA sticker rating of 17 mpg in city driving, but tested 41 percent lower at 10 mpg.
In a study of 303 cars and trucks, model-years 2000 to 2006, Consumer Reports found that shortfalls in miles per gallon occurred in 90 percent of the vehicles tested. The largest discrepancies involved city driving, with some models falling short of claimed mpg by 35 to 50 percent.
A report released in January by the Auto Club of Southern California's Automotive Research Center said 90 percent of the vehicles it tested got mileage worse than the current EPA estimate — by an average of 15.7 percent.
"It's tantamount to sticker shock," said AAA Idaho spokesman Dave Carlson. "Motorists are not getting what's advertised, and that's not right."
Why the discrepancies? Engineers say higher speeds, harder acceleration, heavier traffic, shorter trips, and increasing use of power-hungry accessories such as air conditioning tend to reduce fuel economy but are not accounted for in the EPA's current tests.
The tests were developed in the 1970s, when highway speeds were limited to 55 mph and air conditioning was an expensive option not included in most cars. Those rules allowed car manufacturers to use for testing purposes hand-built prototype vehicles and the most favorable test conditions for maximum fuel economy — low highway speeds, moderate outside temperatures, gradual accelerations. The result has been mpg rates that are nearly impossible for consumers to achieve.
"Current EPA figures are definitely misleading and ultimately expensive for consumers," said David Champion, senior director of Consumer Reports' Auto Test Center.
The discrepancy in fuel economy ratings means that vehicles typically cost hundreds more per year to operate than consumers are led to believe, according to Champion. Put another way, when gas hit $2.37 per gallon last August, the mpg shortchange effectively boosted the price for some motorists to $3.13 per gallon, he said.
The Union of Concerned Scientists, an environmental advocacy group, said their research showed the EPA's tests overstate fuel economy by as much as 30 percent and this year will cost American motorists about $20 billion more on gasoline than they would expect based on the fuel economy stickers.
"The current fuel-economy labeling system is broken," said Don MacKenzie, a vehicles engineer at the union.
Responding to complaints, the EPA earlier this year proposed to change the way it estimates the fuel economy published on vehicle window stickers to make the estimates more consistent with real-world driving. The new proposal would reduce the city mileage estimates for most vehicles, starting in the 2008 model year, by 10 to 20 percent. Highway mileage estimates would drop 5 to 15 percent.
The new proposal calls for "tests that are updated to reflect the way that people drive today," said EPA spokesman John Millett. New windshield stickers are also under consideration, including ones that use a graphic that shows where a particular vehicle's fuel economy falls within the range of models in its class.
Millett said the EPA will conduct additional tests to simulate high-speed driving, rapid acceleration and running vehicle accessories such as air conditioning and power windows. The EPA also will mathematically adjust the results downward to account for conditions such as carrying heavy loads, climbing hills, wind resistance, and deferring vehicle maintenance.
During a public comment period earlier this year, auto makers said they approved of the EPA's intent, but urged a slower phase-in for the new tests.
MacKenzie, the Union of Concerned Scientists engineer, called the EPA's new proposal "a long overdue tune up that better reflects the growing diversity of vehicle technologies and today's driving conditions."
http://www.idahostatesman.com/apps/pbcs.dll/article?AID=/20060516/NEWS02/605160304/1029
Further Information:
The trouble with EPA Mileage Test:
The EPA's fuel economy tests suffer from several fundamental flaws, according to the Union of Concerned Scientists, including:
• Underestimating highway speeds. The EPA highway cycle assumes an average speed of 48 mph and a top speed of 60 mph. Many state highway speed limits are set at or above 65 mph. Government data indicates that fuel economy can drop by 17 percent for modern vehicles that drive at 70 mph instead of 55 mph. Even at 65 mph, fuel economy can drop by nearly 10 percent compared with driving at 55 mph.
• Underestimating city driving conditions. The severity and amount of time spent in stop-and-go urban congestion is getting worse. In 1982, congestion added about seven hours a year to the average person's annual travel, but by 2001 congestion effects had nearly quadrupled to 26 hours per year. While EPA data show that we spend about 62 percent of our time in urban driving, EPA fuel-economy tests still assume only 55 percent.
• Assuming gentle acceleration and braking. The maximum acceleration rate in the EPA test cycles is 3.3 mph per second, about the same as going from zero to 60 mph in about 18 seconds. The average new car or truck can accelerate nearly twice as fast. While most consumers don't use all the power in their vehicle, EPA data shows that people accelerate as fast as 15 mph per second, nearly five times the rate in the EPA tests.
• Neglecting real-world outdoor temperatures. The EPA tests are performed between 68 and 86 degrees Fahrenheit. Most states frequently experience weather conditions outside this range and fuel economy can be significantly affected as a result.
• Failing to reflect the use of air conditioning. Fuel-economy tests are run with the air conditioning off, while more than 99 percent of all cars and trucks come with air conditioning.
• Overestimating trip lengths. The EPA city test cycle is 7.5 miles long. EPA's own data, however, indicate that average trip lengths may be only 5 miles long, with typical trips as short as 2.5 miles. Shorter trips often mean lower fuel economy because the engine does not have time to warm up and operate efficiently.
• Ignoring heavier vehicles. Fuel-economy information is not required for nearly 6 million light-duty trucks on the road today. These are SUVs, pickups, and vans rated above 8,500 pounds gross vehicle weight. A recent J. D. Power survey found that the top complaint with the Hummer H2 was its poor fuel economy — consumers just did not know what they were getting into. And if you are a farmer or small business owner who needs a big pickup, you are left in the dark.
EPA has proposed more accurate testing, but for now,
consumers can't rely on gas mileage ratings:
Mike Maharry
Idaho Statesman
The Idaho Statesman | Edition Date: 05-16-2006
As Treasure Valley gasoline prices climb toward $3 a gallon, more new-car buyers are checking the mileage stickers as they shop.
But for at least another year and a half, the numbers calculated by the U.S. Environmental Protection Agency won't give people a true picture of the mileage they can expect from a new car.
Research by various nongovernment agencies show the EPA numbers are grossly inflated — in come cases by as much as 30 to 50 percent.
According to fuel economy tests conducted by Consumer Reports, the four-wheel-drive Jeep Liberty Diesel Ltd., with an EPA city rating of 22 miles per gallon, got only 11 mpg when tested by the magazine.
The hybrid Honda Civic Sedan tested at 26 mpg in city driving, 46 percent below the official EPA rating of 48 mpg.
A large sedan, the Chrysler 300C, had an EPA sticker rating of 17 mpg in city driving, but tested 41 percent lower at 10 mpg.
In a study of 303 cars and trucks, model-years 2000 to 2006, Consumer Reports found that shortfalls in miles per gallon occurred in 90 percent of the vehicles tested. The largest discrepancies involved city driving, with some models falling short of claimed mpg by 35 to 50 percent.
A report released in January by the Auto Club of Southern California's Automotive Research Center said 90 percent of the vehicles it tested got mileage worse than the current EPA estimate — by an average of 15.7 percent.
"It's tantamount to sticker shock," said AAA Idaho spokesman Dave Carlson. "Motorists are not getting what's advertised, and that's not right."
Why the discrepancies? Engineers say higher speeds, harder acceleration, heavier traffic, shorter trips, and increasing use of power-hungry accessories such as air conditioning tend to reduce fuel economy but are not accounted for in the EPA's current tests.
The tests were developed in the 1970s, when highway speeds were limited to 55 mph and air conditioning was an expensive option not included in most cars. Those rules allowed car manufacturers to use for testing purposes hand-built prototype vehicles and the most favorable test conditions for maximum fuel economy — low highway speeds, moderate outside temperatures, gradual accelerations. The result has been mpg rates that are nearly impossible for consumers to achieve.
"Current EPA figures are definitely misleading and ultimately expensive for consumers," said David Champion, senior director of Consumer Reports' Auto Test Center.
The discrepancy in fuel economy ratings means that vehicles typically cost hundreds more per year to operate than consumers are led to believe, according to Champion. Put another way, when gas hit $2.37 per gallon last August, the mpg shortchange effectively boosted the price for some motorists to $3.13 per gallon, he said.
The Union of Concerned Scientists, an environmental advocacy group, said their research showed the EPA's tests overstate fuel economy by as much as 30 percent and this year will cost American motorists about $20 billion more on gasoline than they would expect based on the fuel economy stickers.
"The current fuel-economy labeling system is broken," said Don MacKenzie, a vehicles engineer at the union.
Responding to complaints, the EPA earlier this year proposed to change the way it estimates the fuel economy published on vehicle window stickers to make the estimates more consistent with real-world driving. The new proposal would reduce the city mileage estimates for most vehicles, starting in the 2008 model year, by 10 to 20 percent. Highway mileage estimates would drop 5 to 15 percent.
The new proposal calls for "tests that are updated to reflect the way that people drive today," said EPA spokesman John Millett. New windshield stickers are also under consideration, including ones that use a graphic that shows where a particular vehicle's fuel economy falls within the range of models in its class.
Millett said the EPA will conduct additional tests to simulate high-speed driving, rapid acceleration and running vehicle accessories such as air conditioning and power windows. The EPA also will mathematically adjust the results downward to account for conditions such as carrying heavy loads, climbing hills, wind resistance, and deferring vehicle maintenance.
During a public comment period earlier this year, auto makers said they approved of the EPA's intent, but urged a slower phase-in for the new tests.
MacKenzie, the Union of Concerned Scientists engineer, called the EPA's new proposal "a long overdue tune up that better reflects the growing diversity of vehicle technologies and today's driving conditions."
http://www.idahostatesman.com/apps/pbcs.dll/article?AID=/20060516/NEWS02/605160304/1029
Further Information:
The trouble with EPA Mileage Test:
The EPA's fuel economy tests suffer from several fundamental flaws, according to the Union of Concerned Scientists, including:
• Underestimating highway speeds. The EPA highway cycle assumes an average speed of 48 mph and a top speed of 60 mph. Many state highway speed limits are set at or above 65 mph. Government data indicates that fuel economy can drop by 17 percent for modern vehicles that drive at 70 mph instead of 55 mph. Even at 65 mph, fuel economy can drop by nearly 10 percent compared with driving at 55 mph.
• Underestimating city driving conditions. The severity and amount of time spent in stop-and-go urban congestion is getting worse. In 1982, congestion added about seven hours a year to the average person's annual travel, but by 2001 congestion effects had nearly quadrupled to 26 hours per year. While EPA data show that we spend about 62 percent of our time in urban driving, EPA fuel-economy tests still assume only 55 percent.
• Assuming gentle acceleration and braking. The maximum acceleration rate in the EPA test cycles is 3.3 mph per second, about the same as going from zero to 60 mph in about 18 seconds. The average new car or truck can accelerate nearly twice as fast. While most consumers don't use all the power in their vehicle, EPA data shows that people accelerate as fast as 15 mph per second, nearly five times the rate in the EPA tests.
• Neglecting real-world outdoor temperatures. The EPA tests are performed between 68 and 86 degrees Fahrenheit. Most states frequently experience weather conditions outside this range and fuel economy can be significantly affected as a result.
• Failing to reflect the use of air conditioning. Fuel-economy tests are run with the air conditioning off, while more than 99 percent of all cars and trucks come with air conditioning.
• Overestimating trip lengths. The EPA city test cycle is 7.5 miles long. EPA's own data, however, indicate that average trip lengths may be only 5 miles long, with typical trips as short as 2.5 miles. Shorter trips often mean lower fuel economy because the engine does not have time to warm up and operate efficiently.
• Ignoring heavier vehicles. Fuel-economy information is not required for nearly 6 million light-duty trucks on the road today. These are SUVs, pickups, and vans rated above 8,500 pounds gross vehicle weight. A recent J. D. Power survey found that the top complaint with the Hummer H2 was its poor fuel economy — consumers just did not know what they were getting into. And if you are a farmer or small business owner who needs a big pickup, you are left in the dark.