Wednesday, July 9, 2008

Hypermilers driven to maximize gas mileage

Hypermilers driven to maximize gas mileage (see video)
11:38 PM CDT on Tuesday, July 8, 2008

By IAN HAMILTON / The Dallas Morning News
ihamilton@dallasnews.com

Chuck Thomas regularly putters along on the highway at 50 mph in his Honda Insight, swerves into turns rather than hitting the brakes, and, when nobody is looking, jumps from the car and pushes it into a parking space.

All just to save a little gas.

Mr. Thomas of Lewisville belongs to an emerging subculture born of the ability to track gas mileage via a dashboard gauge. Hypermilers use a variety of techniques to maximize fuel efficiency: airing the tires up to or beyond the recommended pressure, forgoing air conditioning, coasting whenever possible (sometimes with the engine off), timing their arrivals at intersections to hit green lights and traveling around 50 mph on the highway.

Since he began hypermiling, Mr. Thomas has been squeezing 85 to 90 mpg out of his hybrid Insight, a car rated at 53 mpg.

"Fanatic is what the lazy call the dedicated," notes Mr. Thomas at the bottom of his posts at CleanMPG.com, a Web site devoted to the hypermiling community and its fuel-efficient techniques.

Hypermilers cite several reasons for maximizing mileage, including protecting the environment, saving money, having fun while driving, and even decreasing American dependence on foreign oil.

"Hypermiling is a little addictive," said Reid Stewart, an attorney from Irving who started when he bought a BMW with a gas mileage gauge. "It becomes a competition with yourself to see how well you can do."

The mpg gauge is built into virtually every hybrid car and in many newer gas-powered vehicles. Most vehicles without the gauge can have one installed for about $150. It reveals immediately how various conditions, driving habits and even vehicle modifications impact gas mileage.

Depending on the vehicle, optimal speed on the highway is around 47 to 53 mph, according to well-known hypermiler and Illinois resident Wayne Gerdes.

For Mr. Stewart, the revelation came during a business trip. He was not in a rush, so instead of speeding along at 75 or 80 mph, he drove around 60 mph. He boosted gas mileage by 20 percent.

"Then I really started paying attention to the gauge," Mr. Stewart said.

He researched techniques and began to hypermile in the BMW. But he realized he wasn't using the sports car the way it was intended and traded it for a Honda Insight. Now he gets around 100 mpg, double the car's rated fuel economy. He saves substantially on gas and no longer drives aggressively.

"What I notice is that I'm arriving at work a lot more relaxed," he said.

Not everyone agrees that hypermiling is a great idea. Critics suggest it’s rude, dangerous and a hindrance to normal traffic.

Lt. Charles Epperson with the Dallas Police Department’s traffic division said it is potentially hazardous to drive so far under the speed limit.

"I'd rather see a car going down the road at the posted speed limit than going 15 to 20 miles under the limit. It could cause a pretty massive bottleneck," Lt. Epperson said.

Mr. Gerdes said standard hypermiling practices should not aggravate other drivers or impede traffic. In fact, he said, hypermilers can even help regular drivers save gas.

He explained that hypermilers build a large buffer between themselves and the next vehicle that collapses when stop-and-go traffic comes to a standstill. If the timing is right, traffic will be moving again by the time the car coasts through the buffer. This practice sets a constant traffic flow that can improve the fuel economy of the vehicles around them, he said.

And, he said, the same is true about approaching red lights. Hypermilers are practiced in timing light changes so they can coast through green lights rather than stopping and starting at red ones. Other drivers slowed by hypermilers on the way to a red light will benefit, he said.

"If I can hold the whole conga line back to help the entire line save fuel so they catch a green light, I'll do it," Mr. Gerdes said.

Jake Fisher, senior automotive engineer at the Consumer Reports auto test division, said most hypermiling techniques are safe and beneficial, but some drivers may go too far and endanger others.

On a Consumer Reports blog, Mr. Fisher described an episode in which he was following a Honda Insight whose driver was hypermiling. After picking up speed going down a hill, the driver used the momentum to carry the car uphill, slowing with gravity on the way up. The driver maintained a slow speed as the two cars approached an intersection. The Insight missed the green but coasted through the red light anyway.

"You can't be driving for sport, whether it's street racing or trying to get the best gas mileage," Mr. Fisher said in an interview with The Dallas Morning News. "Only a very small minority of them are taking [the techniques] to an extreme.”

Drafting, which is driving behind another vehicle to take advantage of decreased wind resistance, is another way to increase gas mileage.

In 2007, Discovery Channel's Mythbusters TV show demonstrated that driving 50 feet behind a big rig at 55 mph improved gas mileage by about 20 percent. The practice, widely discussed on hypermiler forums, is generally dismissed as overly dangerous. The hosts of the show drew the same conclusion.

Texas Department of Public Safety Trooper Lonny Haschel said vehicles should drive with at least 2 seconds of stopping time between them.

"You're trying to save gas but you're going to maybe end up paying that money back in hospital bills," Trooper Haschel said.

The most dedicated hypermilers are relatively few and mostly hybrid early adopters. Hybrids, with their part-electric and part-gasoline engine, come standard with the mpg gauge and benefit most from hypermiling techniques.

Still, Mr. Gerdes maintains 48.5 mpg in his Honda Accord and 38.5 mpg in his Ford Ranger. Both figures are drastic improvements from the rated economy of the gas-powered vehicles.

Hypermilers do sacrifice travel time for the sake of gas mileage. In a televised event, Mr. Gerdes and a reporter each drove from Chicago to New York in a hybrid Toyota Prius. According to Mr. Gerdes, the reporter made it in 13 hours at 39 mpg. Mr. Gerdes needed 15½ hours, but he did it on one tank of gas at 71 mpg.

"There's a thousand reasons to choose to be a hypermiler," Mr. Gerdes said. "There's only one reason not to, and that's: 'I've got to be there first.'"
KEYS TO BETTER GAS MILEAGE

Digital mileage gauge: This device hooks into the vehicle's computer and gives instant feedback on fuel consumption, allowing drivers to see what practices burn excess fuel. It costs about $150.

Tires: Filling tires to the recommended or maximum pressure can have a big impact on fuel economy. While there is less friction in a highly pressurized tire, it also can make the ride bumpier.

Speed: Varying speeds can be ideal for gas mileage, but driving more than 60 mph always decreases fuel economy substantially. Every 5 mph over 60 mph reduces fuel economy by the equivalent of 30 cents per gallon.

Weight: Keep the car as light as possible. Every 100 pounds off the vehicle can increase fuel economy by 1 percent to 2 percent.

Gas and brake pedals: Only use the pedals when absolutely necessary, which means keeping an eye on the road ahead and planning your drives accordingly. Don’t accelerate toward a stop sign. Coming to a complete stop nets 0 miles per gallon, so setting a pace in a traffic crunch and timing green lights can go a long way toward helping gas mileage.

Sources: fueleconomy.gov and hypermiling expert Wayne Gerdes

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