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Cave Junction, Oregon, was once, long ago, the center of a gold rush boom that, like so many booms, ultimately consumed its host. Prospectors mined the land around the towns in an ever-tightening circle, until the only gold left was below the saloons, assayers and burlesque halls. Those fell next. The towns were mined right out from under themselves—with no trace left of the old frontier burgs but scars in the earth.
The people who trickled back, decades later, came to satisfy a different urge: not to pursue something but to escape it. Certain hardy members of the hippie diaspora of the ’60s realized that you could live out here entirely under the radar and off the grid. With no one to badger you, you could pursue your own idiosyncratic dreams. You could, in fact, quietly build your better mousetrap and wait until the right time to spring it on the world—the very moment when the world needed saving.
On a lonely stretch of blue highway near the treehouse he lives in and the workshop where he’s been refining that mousetrap, Charley Greenwood slips into the driver’s seat of the FM-4 HumanCar. Or rather, the seat the driver would occupy in a regular car. You don’t “drive” the HumanCar; you row it. It’s the pulling and pushing of the four passengers, converted by a four-gear transmission into rotational thrust, that powers the car at 25 or 30 mph easily, and up to 60 or so on a good downslope. (Where you go in the HumanCar is your business. But rest assured, it won’t be to the gym.)
Charley and I sit up front, his son (and HumanCar, Inc.’s CEO) Chuck in back—none of us so much in the car as on it, for the FM-4 is all bones, with no roof or sides or even fairings. It feels like a cross between a railway push car and a hospital bed. How do you steer a car that every passenger is busy rowing? By leaning in the direction of the turn, or “body steering,” which turns the front wheels. The riders in back don’t steer. They are simply, as Charley puts it, “power monkeys.” Charley grasps the handles the way you would ski poles. A mechanical engineer, he has the looks and manner of a professor but the hands of a laborer. Machine oil has turned his fingertips into blackened kielbasas.
A tiny part has gone missing from the car, preventing it from using all its gears, so we set it in third, which creates an inertia bear at the outset as we get the 300-pound vehicle moving. A kind of automated firing order distributes the torque like an engine as we heave on the oars in sequence—pop pop pop pop. The car picks up speed. And then it starts drifting lazily in the lane: my fault. The brute pull through the power zone and the finesse of the steering are too much for my brain. “There’s a learning curve, for sure,” Chuck says. “That’s why it’s not going to be something anyone can just buy and drive away in. People are going to have to get training, and you’re probably going to have to be licensed.”
On the steep downhill of nearby Happy Camp Road, the HumanCar has taken corners designed for 30 mph, max, at 60. Once, on an early test run, a police officer motioned Charley to the side of the road. He walked slowly around the car, his face a mask. What the hell was this? It was a low-mass vehicle, Charley explained. Not a car at all. “I get it,” the cop said. “You’re going to take it down the mountain at 70 mph, without license plates, and it’s going to be legal because you don’t have a motor.” Charley replied: “You’re very smart.” The cop put his face right in Charley’s. “Well, let’s get at ‘er,” he said finally. “I’ll run cover for you.”
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Say this about Charley Greenwood’s HumanCar: It’s out there. And once the novelty fades, all out-there contraptions invite the question: Why does this exist? What is the problem to which this is the solution? Greenwood’s answer: Name it. Take your pick of the major ills of the postindustrial West, from foreign-oil dependence to obesity to the demise of community. The bigger the problems, sometimes, the simpler the solutions. That’s what popped into Greenwood’s head one day way back in 1968 when he sat stuck in traffic on a California freeway and looked around at all the other people in other cars, single drivers, a lot of them fat as walruses, and he saw America’s future there. He flashed on his HumanCar—or something like it—as an answer, “a knockout punch for all the problems of human mobility and health,” as Chuck puts it.
And now, 40 years later, Charley and Chuck are getting ready to bring to market the next-gen HumanCar, a hybrid that’s a world-first: human/electric. They call it the Imagine, a vehicle that, by easily schlepping people at commuting speed, at virtually no cost, will, Charley predicts, “change the face of human mobility.”
“In five years,” Chuck enthuses, in a moment of perhaps overardent optimism, “one million people will be driving HumanCars.”
Harvesting Negawatts
The internal combustion engine is doomed. U.S. automakers are hogs on ice, scrambling. Green energy is the new favorite sandbox of the dot-com billionaires, now that the X Prize for the first private space shuttle has been nabbed. Most everyone agrees that renewable power is the only hope, and that the conversation about this had better be wide and urgent.
Even so, human power seems on the surface to be an outlier even among the outliers. We don’t normally think of our friends and neighbors as motors. But maybe the moment approaches, as petroleum woes deepen and climate-change fears bite in, when we will be inspired to start.
Consider: Careening into a future where no single source of power will supply all our needs (nuclear, solar, tidal and wind will each have a niche), and what’s this under our nose? A highly efficient, nonpolluting short-stroke engine whose energy is mostly wasted. And not just one: six billion of them. If we could harvest even some of the power that’s squandered as heat, we could—well, what could we do?
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In the past two years, the conver-sation about human power has opened up. All sorts of schemes are emerging. Some are intriguing (“crowd farming”: designing cities to draw on the energy the masses produce every day as they churn through revolving doors, tromp down sidewalks, depress turnstiles in subway stations, and vibrate dance floors). Some are mere YouTube fodder (the pedal-powered lawnmower, the pedal-powered snowplow). And some, whose inventors would no doubt be consigned to academic obscurity were it not for the current convergence of global needs, are already quiet additions to modern life—like Lawrence Rome’s backpack. Rome, a biologist at the University of Pennsylvania, has developed a pack that generates electricity from the subtle bouncing motion created as its wearer walks.
The whole field is pregnant with questions, and they are big ones. How potentially game-changing are the best ideas? If we buy in, might we in the bargain recover something invaluable—the vital, animal nature that we lost, too gradually to notice, when we became a culture of turnpikes and cubicles? Or are the implications more dire? Like: If this catches on, it will be because something very, very bad has happened.
First let’s gather perspective, starting with this unfortunate fact: Tapping into the human race is not going to heat many buildings. “You have to think about the relative magnitudes of power,” says Max Donelan, the chief science officer of Bionic Power, Inc., a company that’s developing a knee brace he invented for aid workers and soldiers that produces a continuous 5 to 10 watts by harnessing the power of the wearer’s gait. “If you took all of the world’s adults and put them on stationary bicycles and had them ride for eight hours a day to generate electricity, they’d crank out 80 gigawatts—roughly equivalent to 11 nuclear power plants. That’s still only half of 1 percent of our energy needs.”
But transportation remains an area in which human power is enough, in which it makes sense to try. Human-powered vehicles are a viable part of the future of transportation for one crucial reason: They don’t do what cars do.
Every tankful of gasoline burned in a car engine emits about 220 pounds of carbon, so to take a single car out of play is to keep literally tons of CO2 out of the atmosphere per year. Even if each American made the much less extreme choice of cycling instead of driving just one day a week, it would save roughly 40 million barrels of fuel a month—which accounts for more than half the oil we import from the Persian Gulf. Human power doesn’t produce megawatts of energy—far from it. What it does produce in spades is “negawatts,” which are every bit as important. It’s not what human power adds to the ledger, in other words, but the huge energy sinks it removes anytime some guy in Cleveland, tuning in to the morning news and hearing about traffic jams and the soaring price of gas, says, To hell with it, I’m not driving today. But what will he do instead? That’s what the human-powered-vehicle visionaries are cooking up.
The Bullet Bikes
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It’s the first warm day of the summer in Toronto, and throngs of bicyclists and in-line skaters are out on the paved paths along the lakeshore. Transit workers, as it happens, have threatened a strike for next Monday. People are tuning up their gams in anticipation that they’ll need to be getting to work under their own steam. And threading among them at twice their speed and three times their grace, here comes Ray Mickevicius.
He sits recumbent in the open cockpit of his Quest velomobile, a bullet-shaped, human-powered tricycle of Dutch design. It looks less like a bicycle than a soapbox derby car made by your dad, if your dad was an engineer at the Jet Propulsion Laboratory. Mickevicius (pronounced “mi-kev-ik-us”), a compact fellow with a baby face and shampoo-commercial hair, is a Toronto lawyer who imports European velomobiles for customers from Vancouver to Texas. He’s currently overseeing the production of a homegrown velomobile, based on a high-riding German model called the Cab-Bike, at a plant in Toronto. (A velomobile is subject to the same laws as bicycles. Only if you add a motor does it become a low-mass vehicle, with its speed capped at between 25 and 35 mph, depending on the state. Go faster than that, and you’re a car, and therefore subject to licensing, mandatory crash tests, and so on. On this day I’m tagging along behind him in a quiet, full-suspension, rear-wheel-drive German velomobile called a Versatile. A couple minutes ago, without working all that hard, we both hit 30 mph and now we’ve slowed to around 25, which still feels plenty fast.
“Holy moley!” says a kid of about eight as we zip past. People who see the velomobile invariably wonder how it’s powered. “One of my riders, the police pulled him over,” Mickevicius says. “They just couldn’t believe he didn’t have a motor.” The Quest, repeatedly wind-tunnel tested, is so ingeniously engineered that not only does it cut the wind, but in crosswinds “it actually gets a pull,” Mickevicius says, “like a sail.”
This weekend, the competitive cyclists are out in force, in their Italian racing caps and Lycra bodysuits, and when we pass them they have a tendency to speed up. I monitor them in my rearview mirror. At 15 mph, they’re right there. At 20 they’re right there. Twenty-five, still there. And then they’re gone. Beyond 25 mph they suddenly fall away, because it’s at that speed that the curve of output versus effort flattens, as wind resistance simply prevents humans on bicycles from accelerating further. To go twice as fast, a cyclist has to use eight times the effort.
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At a traffic light, I stop and wait for the guy who’s been tailing me. “You drafting?” I ask. He shakes his head. “There is no draft,” he says between gasps. “The air goes right over you.”
This is the working equation with land transportation: To go faster, you either increase power or you reduce drag. If you reduce drag enough, you can go fast with very little power—the household-lightbulb-level wattage a human puts out is plenty. It’s something Chester Kyle understood implicitly.
It was Kyle who in 1972, as a mechanical engineer at California State University, Long Beach, decided to test how significantly you could boost the speed of a bicycle if you dramatically reduced wind resistance. He designed the first streamlined bike in America, and in 1974 the American Olympic cyclist Ron Skarin climbed onto it and set a new human-powered speed record. Three years later, a wiry amateur cyclist named Bryan Allen piloted the Gossamer Condor into history as the first successful human-powered aircraft. As co-founder of the International Human Powered Vehicle Association, Kyle was asked at the time to comment on this hot new thing called human power. Where were the breakthroughs going to come from? Well, human-powered flight wasn’t going to be practical anytime soon, he said. (He was right.) But land transportation was a different story. Recumbent bikes encased in bullet-shaped fairings “are the most efficient land transportation ever seen,” Kyle said. “If these vehicles were burning gasoline, they would be getting about 3,000 miles per gallon.”
“Human-powered vehicles are just unbelievably efficient,” says Sam Whittingham, a custom-bicycle builder from British Columbia who last year claimed the “decimach prize” by becoming the first person to travel at one tenth the speed of sound on land (just over 82 mph) using muscle power alone. “The fact that 100 watts will carry you at 30 or 40 kilometers an hour is amazing.” Against that, the image of whole cities choked with vehicles weighing a couple hundred times as much and sucking exponentially more power, seems like . . . actually, an opportunity.
The Hybrid Boost
If the humble bicycle tells the story of where all this began, it also shows where it might be going. One line of thinking is that the bicycle is itself the killer app, if you make it right—if, that is, you acknowledge that although human muscle is kind of miraculous, most people, much of the time, need a little extra jam.
This was what the aeronautical-engineering legend Paul MacCready came to believe. MacCready, who created the Gossamer Condor and pioneered the electric car, concluded in the last decade of his life that of all the world-saving options available, the hybrid bike was the most practical and efficient. “He thought if we could get 40 percent of people out of their cars, the planet had a chance,” recalls Marcus Levison-Hays, a bicycle maker in Sausalito, California, who was mentored by MacCready, “and he believed the geared-motor method was the way to get there.” MacCready’s own invention, the Charger, took the existing model of the electric bike and gave it a few cool twists: The half-horsepower motor sensed the torque you were applying and gave it back, with interest. You could park the bike, lock it up, and detach the battery and control pack and carry them away like a briefcase (albeit one full of bricks).
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Today’s cutting-edge hybrid bikes are pushing MacCready’s vision into a future he never lived to see. There are bicycles that run on hydrogen fuel cells (from Shanghai-based Pearl Hydrogen) and solar bicycles that trickle-charge from photovoltaic cells (a Canadian company called Thera-P Products). The Tesla Roadster of practical hybrid bikes—elitist even by the company’s own admission—is probably the Optibike OB1 (MSRP: $13,000), with an oil-cooled brushless motor that kicks out, almost silently, 850 watts.
Levison-Hays believes MacCready wasn’t wrong; he was just early. Even as MacCready’s Charger was tanking in the marketplace, Levison-Hays pressed ahead with his own design, the Pi, a $2,450 semi-recumbent that morphs to fit riders of different sizes. It packs 750 watts and a NuVinci continuously variable transmission that allows it to shift gears the way cars do: seamlessly and automatically. Upgrades include a GPS transponder embedded in the giant main tube so you can track the bike if it’s stolen and a photovoltaic-cell umbrella that unfolds in a big, sun-catching arch when the bike is parked, charging the battery. “Our customer base isn’t bicyclists who want a better bicycle,” he says. “It’s drivers who want to shelve their car. We want this to be as ubiquitous as an MP3 player.”
The bicycle is the common denominator of all human-power ideas. And so it’s fitting that bicycle technology is propelling the most blue-sky-ambitious application of all: human-powered rapid transit.
The Homer Simpson Test
At a March 2006 meeting of the organization Auto-Free New York, a local man named Fred James stood up and explained his plan for an elevated human-powered monorail. It boiled down to simple physics. Even a mass-transit system doesn’t need much power to run if you keep each part of it feather-light, he said. A gazelle doesn’t need an elephant’s 50-pound heart to go three times its speed. “They’re using vehicles of 100 tons to move people,” James said. “That’s like everyone wearing 400 pounds of chain mail. If we designed cellphones the way we designed transit, we’d have to carry the phones in backpacks.”
What you want to think about, James said, is removing impediments one by one. Reduce air resistance, and—as the velomobile proves—you’re already going at urban automotive-commuting speed. Reduce air resistance and rolling resistance (on smooth, low-friction steel rails), and you can go faster. Add a 600-watt hub motor, and now you have speed to burn, speed that must be governed to avoid injury.
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Emboldened by a rapturous response from the Auto-Free folks, James began refining the idea, posting on urban-transportation Web sites like Streetsblog.org. One Saturday morning last August, he found himself mapping out the monorail concept as he cruised up the middle of Park Avenue on his knockabout Cannondale. It was the first day of New York’s “Summer Streets” experiment, wherein Mayor Michael Bloomberg closed a 6.9-mile-long swath from the Upper East Side to the Brooklyn Bridge to all but human-powered traffic. (Why? Just to see what it looks and feels like to do that. To see what the city becomes.) James vanished into the tunnel below Park Avenue just south of Grand Central Station—a stretch most Manhattanites see only through the windows of a cab—and stopped for a breather after emerging on the far side, as the road rises to go over 42nd Street and around the train station.
“Here, look. This is what I’m talking about,” he said, fingering the steel guardrail that runs along the top of the overpass to prevent motorists who jump the sidewalk from plummeting onto the street. “The line itself wouldn’t need to be much wider than this. You’d have a little sleeve on the underside of the vehicle, on a hinge. You fold it up when you’re just riding around, and then you can click it down into place around the rail, and that’s what steers you. It’s self-steering and self-balancing. Then—just pedal!
“Even in places like Amsterdam, bicycles are only used by 40 or 50 percent of the people,” he said. “You want a way bigger ridership than that. For this to go over big, it has to be easy for everyone to use, from young kids to grandmothers. And the whole infrastructure would be relatively cheap. [New York’s] Metropolitan Transit Authority goes through $9 billion a year—just the running of it. But for less than $1 million, you could build a primitive prototype line farther out, maybe along the Hudson River near Bard College [north of the city], following the railroad there, and it would work pretty well right away.”
James is not an engineer. In his day job, he builds financial databases for banks. He majored in physics at Columbia University but dropped out in 1977 to promote a film he made called A Place to Live, an early documentary on passive solar design that, he says, helped persuade Jimmy Carter to put solar panels on the roof of the White House. (James finally went back to Columbia in 1991 to finish his degree.)
The human-power movement is hospitable ground for such outsiders, people who might not have the credentials to convince the powers that be that what they’re proposing can be done practically but who are clear-headed enough to know and explain why it should be done. The curious Everyman is an expert in human power in a way that he isn’t in, say, nuclear energy or solar harvesting, technologies that for most of us are indistinguishable from magic. (That said, funding bodies have thus far tended to see James’s monorail as indistinguishable from a pipe dream. The New York State Energy Research and Development Authority has already turned him down once for a grant. “He’s up against schemes that are far more practical,” a spokesman said.)
Whenever James is explaining his idea to people and he notices them scouting for the exits, he points out that human-powered rapid transit isn’t just some idea he thought up while waiting for the macaroni to boil. It actually has a long history, beginning a century ago when the bicycle “fad” produced various prototypes of suspended “bicycle railroad systems” that people could tool around on, mostly for fun. The thing about most of these human-power schemes is that they aren’t purely about human power. They depend on some kind of a leg up—be it from gravity, wind or electric power. When you start talking about mass adoption of human power, you have to face some hard truths about human psychology.
“I have a metric that I use,” says Mitchell Joachim, a professor at the Columbia Graduate School of Architecture and inventor of the still-in-progress Soft Car, a stackable supercompact urban vehicle powered by small electric motors in the wheels. “It’s the Homer Simpson metric. Homer is not going to use his body for anything. That’s the American value system in a nutshell. And that’s what we who are trying to design alternative transportation are fighting against. We’ve got to make something that’s clean, cheap and mechanically efficient without the individual feeling the physical consequences. That’s tough.”
Even Whittingham, the world’s fastest man on two wheels, who has a heavy investment both professionally and psychologically in pure human power, sees the difficulty of getting people to choose it so long as there’s an option not to. “I notice the problem even in myself,” he says. “I’m pretty fit. I ride my bike a lot. I like riding my bike. And yet I still jump in the car. And as I get older, it happens more and more.”
MacCready so believed in his hybrid-electric bike the Charger that he sank into its development part of the small fortune he had made selling solar-powered surveillance drones to the U.S. military. “Paul lent me one for a race,” Chester Kyle recalls. “It was beautiful. The only problem was that nobody bought ’em. Why not? Because you can’t take 200 million people and sell them on the idea of using their bodies when they don’t strictly have to.”
Keeping It I-Real
In late September, the Greenwoods pulled the tarp off the Imagine HumanCar at an exhibition in Chicago of futuristic technology. Its fairing gleamed rich orange under the fluorescent lights of the convention hall. A stack of cards explained how the two permanent-magnet DC motors would torque you up from a dead stop to 35 mph in four to six seconds. The car would sense the effort you were putting in and give you just that much back, so the resistance would be about the same as pulling on a bungee cord.
But the Imagine still wasn’t ready to run, so they had also brought the original FM-4 HumanCar, hooked it up to a dynamometer, and invited passersby to hop in and see how much power they could put out. Four brawny med students pushed the needle to 2,000 watts. An economic gloom had fallen over Chicago, and more than one observer seemed to see the HumanCar as a harbinger of the apocalypse, a Mad Max vehicle. “This is what it’s come to,” they said, shaking their heads.
About 20 yards away, a little auto manufacturer called Toyota also had a booth, where it was flaunting its own personal-mobility device, the i-REAL. The company (as the Japanese engineers told the Greenwoods in halting English, after the boys from Oregon had loosened them up with a game of hacky sack) had been burning millions of dollars of R&D money to develop a kind of sit-down Segway for the able-bodied, with fabulous contours, a moveable wheelbase and a top speed of about 20 mph. The i-REAL is an eccentric bet in the eco-mobility sweepstakes, but it may end up being a very pragmatic one. Essentially it’s a bet on Homer Simpson. A bet that, given a choice, our inner “endurance predator”—so long gone from the savanna now that the muscles no longer remember what Job One once was—will take a free ride every time. You might think it would give the human-power tribe pause. You would be wrong.
“It just shows you how far off-base they are with their concept of a net-zero vehicle,” says Chuck Greenwood. “It actually gave us confidence. Not only can we compete with Toyota; we’re going to show them the way.”
Bruce Grierson is the author, most recently, of the book U-Turn.