Sarah Boisvert was driving down Beacon Street, more cheerful than she should have been on a congested Friday afternoon. Then again, she had made it through successive green lights without having to waste gas by hitting her car's brakes — a happy situation known as "riding the green wave" by a certain set of road warriors.

They are the hypermilers — you know, those virtuous types who are obsessed with maximizing fuel economy. Many of their techniques involve no more than common sense and a Zen approach to the road. Hypermilers ask "What would a Boston driver do?" and then pretty much do the reverse.

Some are Prius drivers for whom the hybrid's already admirable 51/48 miles-per-gallon fuel efficiency isn't sufficient. Others want to get a bit more from their gas-hungry SUVs or pickups. The founder of a popular hypermiling competition, Eric Powers, said that the vigilant can beat the Environmental Protection Agency estimates by an impressive 50 percent, and the EPA reports that aggressive driving (namely the antithesis of hypermiling) can lower gas mileage by 33 percent on the highway.

Statistics on hypermilers are hard to come by, but signs of interest abound. A prominent hypermiling website,, claims more than 15,000 members. "We see an increase of about 2,000 members every year," said Wayne Gerdes, the site's founder and the man credited with coining the term.

Not only are sales of ScanGauge II, a plug-in gadget that retails for $160 and monitors fuel consumption, growing, but the manufacturer, Linear Logic in Arizona, recently introduced a second product that makes monitoring gas consumption even easier. "The more people hear about hypermiling, the more they get interested," said marketing manager Joey Snyder.

And, perhaps most telling: Hypermiling may soon have its own app. In July, a Massachusetts Institute of Technology-Princeton team won an award from the Association for Computing Machinery for a system of dashboard-mounted smartphones that allows users to collect information about traffic signals and slow down accordingly. SignalGuru detects the current color of traffic signals and uses information gathered from participating nearby mobile phones to predict the lights' future color and timing. In tests conducted in Cambridge, the app helped drivers cut fuel consumption by 20 percent by reducing idling and accelerating from a standstill.

With gas prices high and the economy low, and too much rage and distraction on the road, what's not to like about hypermiling? "It has actually reduced my cellphone usage," Boisvert, 56, of Plymouth, said as she turned her 2005 Honda Accord hybrid, very slowly. There's simply less time to be distracted by the phone when there's a dashboard fuel-consumption display to focus on.

Boisvert estimates that her techniques save hundreds of dollars a year on gas, and said one of her favorite tricks is coasting downhill and then eschewing the brake pedal as the car slows as long as it is legally, physically, and psychologically possible. Her goal is DWB, as they say in hypermiler forums, or driving without brakes. "But I won't hit a pedestrian," she said, very seriously.

Hypermiling started to break through to the mainstream in 2008, said Gerdes. That's when gas prices topped $4 a gallon, the New Oxford American Dictionary named it the word of the year, and a high-profile NASCAR driver, Dale Earnhardt Jr., employed the "pulse and glide" hypermiling trick to stretch his fuel and coast to victory at the Michigan International Speedway.

Many converts want to save money or the planet — but not all are so noble. For a certain subset, hypermiling is just one more way to prove superiority, the vehicular version of killing the most pigs on Angry Birds, or amassing the most Twitter followers.

"Some people play the stock market and win big," said Alex Lu, a Haverhill transit analyst. "For me, this is it."

When he talks about winning big, he doesn't mean financially. Lu, who drives a 2009 Toyota Corolla, but not very often, calculated his annual savings at a $59.50 per year — a bonanza that might be wiped out by the wear on his transmission caused by his favored method of hypermiling: cruising in neutral.

"People don't recommend it," he said, explaining that the technique is risky because it takes more time to respond to an emergency requiring acceleration, and could cause a car to go out of control down a very steep hill. "But the way I see it, whenever I hit the gas pedal or the brake pedal I see dollar signs."

Still, Lu has his limits. He won't "hard corner," or round corners without braking, or draft Tour de France style behind a truck on the highway, tactics that are not publicly condoned by the hypermiling community. Or the Massachusetts State Police.

Troopers "very strongly recommend against engaging in any of these driving tactics," a spokesman for the State Police emailed about drafting, hard cornering, and coasting in neutral. "Some of them are illegal. All of them are dangerous ... not only to those drivers foolish enough to do these things, but also to the poor innocent person who has the misfortune to cross their path on the wrong day."

But many hypermilers drive in a way that even a trooper would love.

Mike Wiecek, a local mystery writer, started hypermiling to give himself extra incentive to stop driving like a jerk, behavior he developed during long commutes to a former job. "I had become rude and aggressive and I didn't like that about myself," he said.

When being nice for niceness' sake wasn't enough to stop his vehicular aggression, he turned to hypermiling. Saving about $150 a year on gas, acting environmentally responsible — and, most crucially, the chance to feel superior to gas guzzlers — provided the needed motivation.

The new Wiecek coasts to a stop and accelerates slowly in his Honda Civic, a driving style that has the perverse effect of annoying fellow motorists.

"They perceive my driving as being rude to them," he said. "They'll beep and pass in dangerous conditions."

But hypermilers don't care what outsiders think. They've got bigger issues to chew over, such as whether a shorter route with a higher speed limit is preferable to a longer route with a lower speed limit; and when it makes sense to turn off the engine at a red light.

Here's what else they like to talk about. "When you hear someone giving their mileage down to the decimal point, you think, 'We can have a conversation,'" said Powers, founder of the MPG Challenge, which are hypermiling competitions held in Wisconsin and California.

Powers started the MPG Challenge, and also the Green Drive Expo, which showcases hybrid and other eco-friendly vehicles, but he now describes himself as a "recovering" hypermiler.

"I have other things in my life I need to deal with," he said, explaining that he doesn't want to model questionable behavior for his teenage children who are nearing driving age.

And yet, he can't help himself from passing along a little hypermiling humor. "Our joke," he said, "is that a trophy wife is one who can get 58 miles to the gallon."

Copyright 2011 The Boston Globe

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'Hypermilers' nurse every drop of gas
Hypermilers are obsessed with maximizing fuel economy, and their driving techniques range from common sense to illegal and dangerous.