Dean Kamen is turning his private island into a proof of concept for zero-net energy
Photo: Kevin Cooley
Dean Kamen, arguably the world’s most famous living inventor, is in his favorite place. It’s the basement of the main house on his private island, a pristine concrete bunker outfitted with a command station that can monitor and control all aspects of the production and consumption of electric power on the island. The island, off the coast of Connecticut, is called North Dumpling Island, but Kamen, who invented the Segway and is something of an eccentric, calls it the Dumplonian Empire. He, of course, is Lord Dumpling.
Hanging in the foyer of the house is a charred, yellowing copy of North Dumpling’s ancient constitution, a nearly word-for-word match with the U.S. Constitution. The island has its own currency, called—what else?—the Dumpling, dispensed somewhat inconveniently in units of pi. Though the money and the constitution might be tongue in cheek, Kamen’s latest endeavor is anything but: North Dumpling is becoming the world’s first energy-independent nation.
Kamen seceded from the electrical grid last October, when the U.S. Coast Guard, which operates a lighthouse on Kamen’s island, informed him that it was cutting the power to the submarine cable feeding his island. The Guard would instead power the lighthouse with solar panels, with little electricity to spare for the rest of the island. So Kamen did what any self-respecting multimillionaire engineer would do. He went off the grid.
“Off the grid” is a term more likely to come up in connection with grizzled hippies or disturbed militiamen than with famous inventors. But Kamen is determined to use his North Dumpling empire to show that zero-net energy is not only possible now but that it will be very appealing in the future. He has resolved to live off the renewables on the island: a wind turbine and three monster arrays of solar panels, plus Kamen’s beefed-up version of the Stirling engine. It all adds up to a peak generation capacity of just under 25 kilowatts. To coordinate the different sources, Kamen designed an intelligent system that knows, down to an individual solar panel or light source, how much energy is being produced and consumed on the island and, based on that information, negotiates the relationship between the two in real time. It is this system that he monitors and controls from his basement command center.
LED Island: No filaments allowed. Photo: Kevin Cooley
Kamen has many strategies to minimize his energy use, but the big breakthrough is the island’s lighting. With the help of his friend Fritz Morgan, chief technology officer at Philips Color Kinetics, in Burlington, Mass., Kamen has replaced every bulb and fixture on his island with light-emitting diodes. That switch cut the power he needed to light his lair by 50 to 70 percent.
LEDs last about 30 times as long as incandescent bulbs and three to four times as long as compact fluorescents. And they’re gorgeous. They wash the island in colors that cycle through the rainbow (and they can be set to a disco beat, but that’s another story). Just as stunning is the system’s engineering marvel that lets Kamen control every circuit on his island empire from anywhere in the world.
Kamen flits by helicopter between North Dumpling and his main residence, a majestic house in Manchester, N.H., near his Deka Research and Development Corp. in a row of refurbished mill buildings. If you can’t hitch a ride to the island with Kamen in his helicopter, then you board a boat for the 20-minute ride from the Noank Shipyard, near Mystic, Conn. The boat docks on the northeastern edge of the island, made up of 1.2 hectares of landscaping and smooth pebbles, at an ancient pier of gray-washed New England wood that leads to a boathouse. A few steps from the boathouse, on a rocky beach facing east, is the caretaker’s cottage, near a rack of blue-black solar panels. Up a grassy hill and to the west is the stately main house, a shingled, weathered, asymmetrical Colonial that’s wrapped around a lighthouse towering above.
The island’s four arrays of solar panels have a combined peak output of 12.2 kW. A 10-kW wind turbine that looks like a cartoon missile, made by Bergey Windpower Co., perches on a lattice tower 25 meters above the island. The Stirling engine in the basement can contribute another 2 kW if necessary.
Kamen Unplugged: Dean Kamen sits in the cupola of the 160-year-old lighthouse that started it all. Photo: Kevin Cooley
Kamen deploys this patchwork of sources and generators using a system he designed with a team of engineers at Teletrol Systems, another of his companies, also based in New Hampshire. The software acts like a central nervous system, monitoring loads and choreographing the various energy sources to make sure energy consumption on the island never outpaces generation.
Against one spotless corner in the basement is a big console made of sleek, pale bamboo—“Renewable!” Kamen crows—smoothly inlaid with a flat touch-screen display. Here he can see, in real time, exactly how much power is being produced by his renewables and how much is being siphoned by every single process on the island, down to the individual LED fixtures.
Along the opposing wall, the custom control electronics for the Teletrol system hum quietly in glinting server racks. Basically, the system establishes priorities among the power drains: At the very top are the necessary functions—lighting LEDs currently in use, heating or purifying water, or cooling the house. Heating is not really an issue, because the island isn’t accessible on the coldest days, when the swell in the surrounding seas can reach 9 meters. The house is cooled centrally with ultraefficient central heat exchangers.
After addressing immediate needs, the system diverts any extra power to a bank of batteries. “That way, we don’t have to waste any voltage generating energy to charge them,” says Kamen.
The formal dining room gleams with the soft yellow light of two flickering candelabras. But we’re standing in the next room, around the kitchen counters, eating cold-cut sandwiches on hamburger rolls and washing them down with warm beer. Kamen is telling us about a speech he gave as the keynote speaker at a high-profile event organized by Minneapolis-based Medtronic, the medical-device colossus. Waiting backstage as the master of ceremonies and Medtronic senior VP Stephen Oesterle extolled the many inventions of Benjamin Franklin, “I thought, wait a second, I thought I was the one who was giving this talk,” Kamen croaks, his tone in a perpetual tug-of-war between acerbic and affable. And then, as Kamen was ushered onstage to give his speech, he heard, “…and that’s why we think Dean Kamen is the reincarnation of Benjamin Franklin!”
“Of course it’s all crap,” Kamen says. But then, eyebrows rising along with his index finger, he amends himself. “Benjamin Franklin reinvented glasses as bifocals. I also took something that had been around forever and reinvented it.” That would be the wheelchair. Kamen’s version, the iBot, can hop curbs and raise its occupant to eye level with a standing person. Kamen also invented a wearable insulin pump and a prosthetic arm.
After all this it should be no surprise that Kamen wields some influence. Campaigning in New Hampshire in late 2007, Barack Obama made sure to send an emissary to Deka. But Kamen says he talks to politicians about only two things: bringing electricity and clean water to the developing world, and FIRST (For Inspiration and Recognition of Science and Technology), a program he developed that injects science and technology into elementary, middle, and high school classrooms in the United States. The vehicle? Robots. Contenders are divided up into robot-building teams. They face off in elimination rounds throughout the year, culminating in a championship in which a winning team is crowned. FIRST gives technical fields the cachet that was once reserved for athletics.
The FIRSTies worship Kamen. They proclaim their devotion on message boards, where they identify themselves by their team numbers (“I’m on 339!” “Team 862 Represent!” “Third year on team 88!”). The most devoted extend that love even to Kamen’s mother, who has attended these events religiously since Kamen founded the organization 20 years ago.
Kamen, who hobnobs with George H.W. Bush and ice-cream activists Ben and Jerry and flies around in a souped-up Enstrom 480 helicopter (the souping-up is of his own design, natch), has been called a rock star inventor. But it’s hard to reconcile the moniker with his unabashed geekery and top-to-toe denim uniform. No Savile Row for Kamen, though he could probably afford to buy Savile Row—the street, not a suit.
The same lack of pretense is apparent on North Dumpling, which is going through an awkward phase on this cool May evening. Here in the kitchen, high-end stainless appliances, including a massive side-by-side refrigerator and a vast range hood, bump elbows with frumpy, vaguely olive cabinetry. The cabinets are not long for this world.
In fact, the whole North Dumpling complex is in the midst of a complete face-lift. The point is to showcase lighting, the most visible aspect of Kamen’s rethinking of the way we use energy.
Mood Lighting: At night, outdoor LED fixtures wash the island in a moody blue. Photo: Kevin Cooley
“Do I have to fly anyone to the mainland?” Kamen asks around the small kitchen. If somebody needed some toothpaste or something, Kamen would chauffeur them to the New London, Conn., airport in the helicopter. No big deal. He’s had over 10 000 hours of flight time. For him, it’s not much more special than driving a car.
Nobody needs anything.
“Then give me a beer!” he says to Morgan, the only man on the island with a pressed shirt. Morgan, a neat blond in starched maroon plaid and khakis, is on a sabbatical from Philips Color Kinetics while he helps Kamen with the project. He knows everything there is to know about the LED systems, of course, because they’re all made by his company. He reels off models and ratings without pausing for breath.
Morgan estimates that the cost of all this high-tech lighting would have been about US $100 000. But that figure doesn’t mean much, he adds, because some of the devices installed here aren’t even on the market yet. Morgan insists that the price will fall steeply as LED lights become prevalent.
Consider, for example, the ColorBlast Powercore lights that shine on the island’s miniature re-creation of Stonehenge. (Yes, when Kamen bought the island it came with a little Stonehenge. As with the original, no one knows who built it.) The lights are rectangular devices with alternating rows of eight red, blue, and green LEDs. “When different fractions of the LED lights are lit, any of 16.7 million possible colors can be created,” Morgan says. They create additive color the way a computer screen uses different mixtures of red, green, and blue pixels. The fixtures cost about $1000, Morgan says, including the marine-rated housings that protect them from the brutal New England winter storms. Average power consumption on North Dumpling is about 2500 watts. With every single light on the island shining—including the main house, Stonehenge, the guesthouse, and the caretaker’s cottage—total consumption peaks at 5000 watts.
Stone Washed: The miniature Stonehenge replica is perpetually awash in disco colors from the marine-rated LED fixtures. Photo: Kevin Cooley
An average household dedicates approximately 20 percent of its energy budget to lighting. Here’s how that 20 percent can be manipulated by replacing incandescents with LED lighting. A traditional 60-watt incandescent bulb lasts about 1500 hours and has only a 2.5 percent efficiency because it wastes most of its energy as heat. Its brightness rating is about 16 lumens per watt, which is a measure of how much luminosity your bulb produces for every watt it eats up. A compact fluorescent lightbulb, or CFL, does much better: A 13- to 15-W bulb has about an 11 percent efficiency, emitting around 75 lm/W. The less-wasteful CFL lasts about 10 times as long as an incandescent (a little under two years).
On the downside, CFL bulbs contain mercury, which means they must be treated and disposed of as hazardous waste. Now consider LEDs. The best of these can pump out a whopping 150 lm/W (from the “raw” chips, not the integrated lamp or system) and function at about 22 percent efficiency. With typical use, that’s at least 11 years without changing a bulb.
Perhaps a dozen countries, including the United States, Australia, and Cuba, have passed laws banning incandescent bulbs, most kicking in by the mid-2010s. With the environmental concerns raised by the toxic content of CFLs, the switch to LEDs is inevitable. Within 10 years, Kamen believes, almost everyone will have some means of locally generating electric power. It’s the only logical solution, he thinks, to an overtaxed, undermaintained national grid that’s vulnerable to any disruption, be it an ice storm or a terrorist attack.
But in Kamen’s native United States (or rather his “neighboring nation,” as he reminds me), LEDs contend with a mixed reputation, a legacy of their evolution. Though they consume much less power than their incandescent counterparts, their light can be lurid and flat. They irradiate more than they illuminate.
At Philips, Morgan has been working to improve the quality of LED light from the hard bluish-white of early LED flashlights. “How do we replace them in a way that has all the benefits of an incandescent but none of the problems?” he recounts. “How do we design the optics so we get one soft shadow, as opposed to a bunch of harsh shadows?” The result was a unit with a cluster of LEDs inside, flanked by reflectors. The light even has a dimmer switch actuated by a microprocessor at its base.
The extent of the challenge is on view in Kamen’s study—lovingly lined with deep brown bookshelves, complete with a ladder to ascend to the topmost shelf in the high-ceilinged room. It appears to be bathed in the sweet, warm glow of recessed incandescents, but in fact these fixtures use LEDs. In lighting lingo, their bulbs are a new kind of PAR 38 lamp (parabolic aluminized reflector). Philips expects to launch the product next year. In fact, the sole surviving fluorescent bulb, in the hallway next to Kamen’s study, proves a telling contrast. The hall light is dingy and sulfurous. In the library, the effect is indistinguishable from that of incandescents—clean, bright, and warm.
The range illustrated by the lights on the island—the disco luminescence of the patterns on Stonehenge; the warm glow of the study; the cool, official mood of the living room; the twinkling coziness of the bar downstairs; the hypnotic blue of the outside lighting that guides the visitor up the byzantine path snaking between houses; and the efficient illumination in the basement—are why this island is the perfect showcase for everything an LED can do, and with so little power draw.
To be sure, going off the grid is anything but cheap. Kamen installed the wind turbine in 1992, but doing the same thing today would likely set your garden-variety island-owning multimillionaire back between $41 000 and $57 000 (including the tilt-up tower that’s necessary for construction because it’s pretty hard to get a crane onto a 1.2-hectare private island). The Evergreen Solar ES series that Kamen had installed in four clusters on the island combine 180- and 205-W solar panels.
With the switchover, Kamen was able to pare the energy consumption of the lighting from 7500 watts down to about 3000—a factor of almost two-thirds. “There are more circuits related to lighting than all the other appliances in the house combined,” Kamen says. “If each incandescent consumes 5 or 10 times as much power as an LED, think about the total energy savings.”
Of course, to take full advantage of the potential savings of LEDs, a homeowner would, like Kamen, have a Teletrol building controller to control the LEDs. These systems start at several thousand dollars and go way up from there. The controller is incredibly granular. Tapping through a succession of screens on the display in the basement, Kamen eventually gets to a plot of the day’s energy generation. Colorful lines represent the different incoming sources: a black line tracks shifts in solar intensity and a paired red line shadows it precisely, representing the current feed to the island’s rechargeable batteries through the charge converters. The wind turbine shows up as a green line below the juddering red and black lines, and it has racked up only 10 kWh, as attested to by the mild blue sea outside. By contrast, although it’s only a quarter past four, the solar panels have already generated a total of 35.97 kWh.
The red and black lines hover at zero during the nighttime hours, creep up a bit around dawn, then rise steeply at around 7 a.m. They hover high on the graph for several hours and then, at the 1 p.m. point, begin to shudder through a series of dips and rises. “Those are clouds passing overhead,” Kamen points out.
But what happens when the island gets neither sun nor wind? That’s when Kamen’s Stirling engine kicks in. Kamen’s reimagining of the 193-year old design is about half the size of a refrigerator, and its job is to convert heat energy into work.
A Stirling engine contains a sealed cylinder, one end hot, the other cool, with a sliding piston that moves the gas back and forth. On the hot side, the gas expands and exerts pressure on a piston; on the cool side, it contracts. Unlike a gasoline or diesel engine, Kamen’s Stirling is an external combustion device. The fuel that heats the gas inside the engine never touches the engine itself. Unlike spark-ignition or compression-ignition vehicle engines, a Stirling doesn’t require that the fuel be mixed with air in a particular ratio. It can run on pretty much any liquid or gas fuel, including diesel, methane, gasoline, or olive oil. Got cow manure? That’ll work, too [see online sidebar, “Electricity From Cow Flops”]. The design is ideal in theory, converting fuel to heat and heat energy into mechanical energy, but one problem remains: The machine generates electricity at an efficiency of only 20 percent. The rest is wasted as heat.
But Kamen says the concept of “waste heat” changes with context. In winter that heat can be diverted to the house, the clothes drier, and the island’s domestic water supply. “Think of it as a furnace that’s also making electricity,” Kamen explains. Harness the heat from the Stirling while it generates electricity and you can get an efficiency darn near 100 percent, he says.
His own machine typically produces 1 kilowatt of electricity, enough to power 128 LED lights, each equivalent to a 60-W incandescent. The engine sits in a far corner of the basement. At the moment, it’s inactive because the solar panels are generating a steady, incoming stream of 2 kW.
The Teletrol system runs an iron-fisted dictatorship over all of these processes. If there’s any excess power, the system uses it to feed the vast bank of custom batteries lining an entire wall of the basement, 24 big red plastic containers that resemble gasoline canisters. These batteries weigh 144 kilograms apiece, cost between $1285 and $2000 a pop, and must have their chemistry checked periodically with a hydrometer.
They’re also truly and deeply rechargeable. They are lead-acid batteries optimized for what’s called a deep discharge cycle, meaning that their charge can be repeatedly and substantially depleted by 80 or 85 percent. For contrast, most battery chemistries typically tolerate at most 5 to 10 percent depletion on a regular basis. The batteries were made by a company called Surrette Battery Co., headquartered in Springhill, N.S., Canada, and Salem, Mass., which specializes in cells optimized for solar and wind-power charging. Each battery comes with a 10-year warranty.
“Every once in a while, we know we’re going to have to depend on these batteries to run the entire island,” Kamen says. They can power the island for three days continuously in the unlikely case that all sources of energy simultaneously go off-line.
The Teletrol display shows the state of the batteries’ charge overnight waning ever so slightly, as minimal, basic processes dip into their charge. The blue line representing the batteries’ state of charge has been rising gradually over the course of the day, as the excess power from the solar panels fills them up.
After the batteries are fully charged, the water in the hot water heater is hot, the lights are off, and no activity is drawing the incoming energy, the system is intelligent enough to survey the house and ask itself whether there is enough purified water. Beneath the island, vast holding tanks are filled with seawater that has been purified to medical grade by Kamen’s vapor-compression distillers, two of which sit in the basement. Inside their four-foot, glass-paneled cabinets, snaking coils of what looks like garden hose wrap around complicated machinery.
Kamen calls his invention the Slingshot and refuses to discuss its design. He asserts that it can derive absolutely pure water from any wet material, even raw sewage or toxic waste. “It’s 40 times as efficient as a standard still would be,” Kamen says. “The goal is to make about 1000 liters of water a day using less total energy than a handheld hair dryer.” He allows himself a little smile.
Wind Power: Dean Kamen’s Bergey wind turbine provides 10-kilowatt peak generation on gusty days. Photo: Kevin Cooley
To be sure, the system has some wrinkles that need to be ironed out before it can be flaunted for the world’s press. Earlier in the day, when we first meet Kamen, he wants to show me how his system works. He excitedly pulls out his laptop, and we sit down in the grassy shade of his helicopter’s tail boom as he tries to show me the laptop-based remote version of the display controller on the basement bamboo console. The only problem is that Dumpling’s wireless network is down. Kamen pecks at his keyboard for about half an hour while I try to find a spot on the screen that isn’t obscured by fingerprints.
Soon, however, North Dumpling’s control system is online. The system will do two things. It will let Kamen log into it when he’s leaving work at Deka, in New Hampshire, to rouse the sleeping house, lighting and heating the house and the water to his specifications in time for his arrival. But even more important, the system will allow people all over the world to peek into the inner workings of the Dumplonian Empire. Virtual visitors worldwide will be able to monitor in real time how much energy the island is generating and consuming. “You’ll be able to see whether we are consuming or producing power,” he says, ”and where it’s going at any moment.”
Today only the LEDs are ready for prime time. By September, the entire island will be, too. “It’s going to make a powerful statement,” Kamen says. “Whether you’re interested in the environment or your own budget, the answer is one thing—stop using incandescent lights.”