Here’s a little puzzle.
One day, on her way to work, a woman decides that she’s going to take a mass-transit system instead of her usual method. Just before she gets on board, she looks at an app on her phone that gives her position with the exact latitude and longitude. The journey is smooth and perfectly satisfactory, despite frequent stops, and when the woman disembarks she checks her phone again. Her latitude and longitude haven’t changed at all. What’s going on?1
The answer: The woman works in a tall office building, and rather than the stairs, she’s taken the elevator.
We don’t tend to think of elevators as mass transportation systems, but they are: they move hundreds of millions of people every day, and China alone is installing 700,000 elevators a year.2
The tallest building in the world, the Burj Khalifa in Dubai, has more than 3 million square feet of floor space. The brilliantly engineered Sears Tower in Chicago (now the Willis Tower) has more than 4 million.3 Imagine such skyscrapers sliced into fifty or sixty low-rise chunks, then surrounding each chunk with a parking lot and connecting all the parking lots together with roads and you’d have an office park the size of a small town. The fact that so many people can work together in huge buildings on compact sites is possible only because of the elevator.
Or, perhaps we should say, because of the safety elevator. Elevators themselves have existed for a long time, typically using the very simple principle of a rope and a pulley. Archimedes is said to have built one in ancient Greece. In 1743, at the Palace of Versailles, Louis XV used one to clandestinely visit his mistress—or, alternatively, so that his mistress could clandestinely visit him.4 The power for King Louis’s secret love-lift was supplied by a chap in a hollow section of wall, standing ready to haul on a rope when required. Other elevators—in Hungary, in China, in Egypt—were powered by draft animals.5 Steam power went further: Matthew Boulton and James Watt, two giants of Britain’s industrial revolution, produced steam engines that ran muscular industrial elevators that hauled coal up from the mines.6 But while these elevators all worked well enough, you wouldn’t want to use them to lift people to any serious height—because, inevitably, something would go wrong. The elevator would plunge down through the shaft, loose ends of the rope flapping in the darkness, passengers screaming into oblivion. Most people can walk up five flights of stairs if they must; nobody in their right mind would want to take an elevator to such a deadly height.
So what was crucial was designing and building an elevator that was not only safe but demonstrably and consistently safe. Such responsibility fell to a man named Elisha Otis. At the 1853 World’s Fair in New York, Otis climbed onto a platform, which was then hoisted high above a crowd of onlookers, nervy with anticipation. The entire contraption looked a little like an executioner’s scaffold. Behind Otis stood a man with an ax, which can only have added to the sense that a spectacular death was about to occur. The axman swung, severing the rope. The crowd gasped; Otis’s platform shuddered—but did not plunge. “All safe, gentlemen, all safe!” boomed Otis. The city landscape was about to be turned on its head by the man who had invented not the elevator, but the elevator brake.7
“Turned on its head” is right—because the new, safe elevators transformed the position of the highest-status areas in the building. When the highest reaches of a six- or seven-story building were reached only by an arduous climb, they used to be the servant’s quarters, the attic for mad aunts, or the garret for struggling artists. After the invention of the elevator, the attic became the loft apartment. The garret became the penthouse.
The elevator is best understood as part of a broader system of urban design. Without the air conditioner, modern glass skyscrapers would be uninhabitable. Without either steel or reinforced concrete, they would be unbuildable. And without the elevator, they would be inaccessible.
Another crucial element of that system was mass public transportation: the subways and other urban transit systems that could bring large numbers of people into dense urban cores. In the quintessential high-rise center, Manhattan, elevators and the subway are symbiotic. Without the density that the skyscrapers provide, it would be hard to run a subway system efficiently; without the subway system, people would struggle to reach the skyscrapers.
The result is a surprisingly green urban environment: more than 80 percent of Manhattanites travel to work by subway, or by bike or on foot, ten times the rate for America as a whole. A similar story can be told for high-rise cities across the planet from Singapore to Sydney. They tend to be highly desirable places to live—as witnessed by people’s willingness to pay high rents to do so. They’re creative, as measured by a high output of patents and a high rate of start-ups. They’re rich, as measured by economic output per person. And relative to rural and suburban areas, they are environmental utopias, with low rates of energy use per person and low consumption of gasoline. This minor miracle—wealth, creativity, and vitality in a modest environmental footprint—would be impossible without the elevator.8
Yet the elevator seems unfairly underrated. We hold it to a higher standard than other forms of transport. We’re pleased if we must wait only a couple minutes for a bus or a train, but grumble if we have to wait twenty seconds for an elevator. Many people are nervous of elevators, yet they are safe—at least ten times safer than escalators.9 The elevator is a faithful servant that is too often ignored. Perhaps this is because using an elevator feels almost like being teleported: the doors close, there is a shift in the feeling of gravity, the doors open again and you’re somewhere else. There is so little sense of place that without signs and LED displays, we wouldn’t have a clue which floor we were emerging into.
While we take the elevator for granted, it continues to evolve. The challenges of ever taller skyscrapers are being met by super-light elevator ropes and computer controllers that will allow two elevators to shuttle up and down a single shaft independently, one above the other. But often the older, simpler ideas still work: for example, making the wait for an elevator pass more quickly by putting full-length mirrors in the elevator lobby. And the elevator is naturally energy efficient because elevator cars have counterweights.10
There’s always room for improvement, of course. The Empire State Building—still the most iconic skyscraper in the world—was recently retrofitted in a $500 million project to reduce the building’s carbon emissions. The retrofit included elevators with regenerative brakes, so that when a full car comes down or an empty car heads up, the elevator supplies power back to the building. 11
But the truth is that the Empire State Building was always energy efficient by the simple virtue of being a densely packed vertical structure next to a subway station. One of the organizations that designed the building’s retrofit is a visionary environmental organization, the Rocky Mountain Institute (RMI)—whose super-efficient, environmentally sustainable headquarters, doubling as a showcase home for founder Amory Lovins, was built high in the Rockies, 180 miles (290 kilometers) from the nearest public transit system.12
RMI has expanded, and staff take pains to use energy-saving technology to get to meetings: buses, electric cars, and teleconferencing. And RMI is a showcase for environmentally efficient design ideas, including high-tech window coatings, krypton-filled triple-glazing, a water-reuse system, and energy-saving heat exchanges.13
But the elevator requires no pains to be taken at all. It’s one of the most environmentally friendly technologies, and it is on display in buildings all around us. The humble elevator is a green mode of transport that moves billions of people every year—and yet is so overlooked that it can hide in plain sight as the answer to a lateral thinking puzzle.