An Electrifying Idea For Roads
Starting this summer, the public buses in the Oberhaching suburb of Munich, Germany, won’t have to be plugged in to charge overnight anymore. Stefan Schelle, the mayor of Oberhaching, is taking advantage of the fact that an innovative startup has its offices in his community: Magment, short for “magnetizing cement,” will install its underground charging pad in the coming months. As soon as that happens, the buses will charge while they wait at the city’s main station or while stored at their overnight quarters.
In his light-filled office, Magment’s co-founder and CEO, Mauricio Esguerra, demonstrates how the new technology works: The lights on his black model car only flash when he puts the miniature Porsche directly atop the induction plate. “This works just like when you charge your iPhone on its charging pad or heat a pot on an induction range. People don’t have to be afraid of magnetic fields or anything like that,” says the 60-year-old Colombia-born entrepreneur. “The induction only gets activated when the storage battery is placed directly on top.
Patented by Esguerra, the “magnetizing concrete” is able to target the charge quite precisely. The batteries will be mounted in a box underneath the vehicles such as the retrofitted public buses. “Look, here’s one passing by,” says Esguerra, pointing out the window as a blue city bus rides past his office.
An invention finds its purpose
Esguerra grew up in Bogotá, studied physics at the Technical University Munich where he fell in love with a German woman, and started a family in her home country. For 15 years, he developed magnetic products, including the magnetizing cement, for Siemens, Europe’s largest industrial manufacturing company. The patent belonged to Siemens, of course. “But there were hardly any electric vehicles yet,” Esguerra says, “and Siemens didn’t quite know what to do with this invention.”
Esguerra changed companies a few times but, in 2015, he got an offer from Siemens. The patent for the magnetizing cement was expiring and Siemens wasn’t interested in keeping it. Would he, as the inventor, want it back? “I did not hesitate a second,” Esguerra remembers with a smile. “I’m a magnetician at heart.” That same year, he founded Magment to finally make use of the technology he created 20 years ago.
To demonstrate how his cement is made, he opens the lid of a plastic bucket filled with cement powder. Mixed in are fingernail-sized black pieces, so-called ferrites, mainly consisting of three ceramic oxides: iron, nickel and zinc. Conventionally, they are used in electronics such as cell phones, computers and cables. Molded in concrete, ferrites create a magnetic field that can transport charge to a vehicle, potentially eliminating range anxiety for EV drivers.
Molded in concrete, ferrites create a magnetic field that can transport charge to a vehicle, potentially eliminating range anxiety for EV drivers.
Magment
“Ferrites have extremely high rejection rates,” Esguerra adds. “It’s comparable to other ceramics: As soon as there is a small tear or crack, the material is rejected. We are talking about a rejection pile of 500,000 tons per year worldwide. There are mountains of unused materials.”
Exactly this fact was the starting point of his research at Siemens: “What can we do with this energy-intensive material? Back then, it was crushed up and mixed into the cement for building streets, without adding any function.” Today, too, the Magment material can simply be mixed with the conventional material and equipment of the cement industry. “We take advantage of the fact that we don’t have to build factories and don’t have high transportation costs."
In addition to saving resources, recycled ferrite also makes concrete more durable.
No plugs, no charging breaks
A young intern in the office next door winds cables around a new coil. These coils will later be lowered underground in a box, connected to the grid and encased in magnetizing concrete. The recipient box looks similar; it’s another coil but smaller, and it will be mounted underneath the carriage of the vehicle. For a car, the battery box would be 25 by 25 centimeters (about 10 inches), for a scooter five by five centimeters (about two inches).
Esguerra pushes an electric scooter into a cemented scooter rack next to his office. The charging pad is invisible. A faint beep is the only sign that it has started charging. “Childs play!” Esguerra says. “Even when someone puts in the scooter a little crooked, the charge still works. Our efficiency rate is up to 96 percent.” From this summer on, hotel chains in Munich will try out this system with their rental scooters, at a price of about 500 Euros per charging station.
Compared to plug-in charging, Magment’s benefits include smaller batteries that charge slower and, therefore, gentler, so they may last longer. Nobody needs to plug in the vehicles manually anymore. “Personally, I’ve had an EV for six years,” Esguerra says, “and how often does it happen that I forgot to plug it in overnight and then start out with a low charge in the morning? Once people get used to the invisible charging system, it will become the norm.“
There are also downsides: Most car companies aren’t ready for the new technology. Hyundai is the first carmaker that announced plans to equip some new models with inductive charging capability. “How many cars are electrified worldwide?” Esguerra asks and gives the answer himself: “One percent. And how many forklifts are electrified? More than 70 percent!” Therefore, Magment focuses on charging forklifts, e-scooters and buses.
Magment has focused most of its efforts on charging forklifts and other vehicle types that are entirely or predominantly electric, unlike cars.
Magment
On the morning of my visit to Esguerra’s office, a developer of the world’s third-biggest forklift manufacturer is there to inspect how the technology works on the ground. In the basement, a Magment engineer drives an electric forklift over a testbed with invisible charging coils, turning on the green charging light. Esguerra opens the interior of the forklift and points out the two batteries. “With our system, the forklift will only need one battery.” The savings, about 7,000 Euro per forklift, will pay for the installation of Magment’s charging system in warehouses, Esguerra calculates. “Less personnel and no unnecessary wait times for charging will lead to further savings,” he says.
To implement the new technology as efficiently as possible, Magment engineers began recording the transport routes of forklifts in warehouses. “It looks like spaghetti diagrams,” Esguerra explains. “Soon you get the areas where the forklifts pass or wait most frequently. This is where you install the chargers underground.” The forklifts will charge while in use, without having to pause for charging breaks. The method could also work for robots, for instance, in warehouses and distribution centers.
Roads of the future could be electric
Potential disadvantages might become apparent once the technology is more broadly in use. Therefore investors were initially reluctant, Esguerra admits. “Some are eager to be the first but most prefer to wait until the technology has been extensively used in real life.”
A clear hurdle today is that electrifying entire freeways with induction coils would cost at least 1 to 1.5 million Euros per kilometer. The German Department for Transportation even calculates overall costs of 14 to 47 million Euros per kilometer. So, the technology may only make sense for areas where vehicles pass or dwell the longest, like the Oberhaching train station or a busy interstate toll booth.
And yet, Magment is ramping up to compete with other companies that build larger inductive charging pads. The company just finished the first 20 meters of a testbed in Indiana, in partnership with the Purdue University and the Indiana Department of Transportation. Magment is poised to build “the world’s first contactless wireless-charging concrete pavement highway segment,” Purdue University announced.
The project, part of Purdue’s ASPIRE (Advancing Sustainability through Powered Infrastructure for Roadway Electrification) program, is financed by the National Science Foundation. “Indiana is known as the Crossroads of America, and we’re committed to fortifying our position as a transportation leader by innovating to support the emerging vehicle technology,” Governor Eric J. Holcomb said. If testing is successful, including the concrete’s capacity to charge heavy trucks operating at higher power (200 kilowatts and above), Indiana plans to identify a highway segment to install Magment’s charging pads. The earliest would be 2023 at best.
In the meantime, buses in the Californian Antelope Valley, trams at Hollywood's Universal Studios and transit buses in Tampa, Florida, are already charging with inductive technology developed by Wave, a company spun out of Utah State University. In Michigan, Governor Gretchen Whitmer announced plans to build a test route for vehicles to charge while driving, in collaboration with the Israel-based company Electreon, and this year contracted to build the first road-based charging system in the U.S. The state is providing support through an innovative grant program.
Costs remain one of the biggest obstacles, but Esguerra’s vision includes the potential that toll roads could charge a premium for inductive charging capabilities. “And in reverse, a driver who has too much energy could feed his surplus into the grid while driving,” Esguerra dreams.
Meanwhile, Wave’s upcoming big projects are moving trucks along a route in Southern California and running a UPS route between Seattle and Portland. Wave CTO Michael Masquelier describes the inductive power transfer his company champions as “similar to a tuning fork. By vibrating that fork, you sent energy through the air and it is received by another tuning fork across the room. So it’s similar to that, but it’s magnetic energy versus sound energy.”
He hopes to partner with Magment, saying that “the magnetizing cement makes installation easier and improves the energy efficiency.” More research is needed to evaluate which company’s technology will prove to be the most efficient, practical, and cost-effective.
Esguerra’s vision includes the potential that toll roads could charge a premium for inductive charging capabilities. “And in reverse, a driver who has too much energy could feed his surplus into the grid while driving,” Esguerra dreams.
The future will soon arrive in the idyllic town of Bad Staffelstein, a quaint tourist destination in the Upper Franconia region of Germany. Visitors will be taken to and from the main station and the popular thermal bath by driverless shuttles. Together with the University of Wuppertal, the regional government of Upper Franconia wants to turn its district into “the center of autonomous driving.” Magment is about to install inductive charging pads at the shuttle stations and the thermal bath, eliminating the need for the shuttles to stop for charging times. No more drivers, no cable, no range anxiety. Masquelier believes that “wireless and autonomous driving go hand in hand.” Science fiction? It will become science reality in spring 2023.
CORRECTION: An earlier version of the story erroneously mentioned that Electreon required overhead cables.
Your phone could show if a bridge is about to collapse
In summer 2017, Thomas Matarazzo, then a postdoctoral researcher at the Massachusetts Institute of Technology, landed in San Francisco with a colleague. They rented two cars, drove up to the Golden Gate bridge, timing it to the city’s rush hour, and rode over to the other side in heavy traffic. Once they reached the other end, they turned around and did it again. And again. And again.
“I drove over that bridge 100 times over five days, back and forth,” says Matarazzo, now an associate director of High-Performance Computing in the Center for Innovation in Engineering at the United States Military Academy, West Point. “It was surprisingly stressful, I never anticipated that. I had to maintain the speed of about 30 miles an hour when the speed limit is 45. I felt bad for everybody behind me.”
Matarazzo had to drive slowly because the quality of data they were collecting depended on it. The pair was designing and testing a new smartphone app that could gather data about the bridge’s structural integrity—a low-cost citizen-scientist alternative to the current industrial methods, which aren’t always possible, partly because they’re expensive and complex. In the era of aging infrastructure, when some bridges in the United States and other countries are structurally unsound to the point of collapsing, such an app could inform authorities about the need for urgent repairs, or at least prompt closing the most dangerous structures.
There are 619,588 bridges in the U.S., and some of them are very old. For example, the Benjamin Franklin Bridge connecting Philadelphia to Camden, N.J., is 96-years-old while the Brooklyn Bridge is 153. So it’s hardly surprising that many could use some upgrades. “In the U.S., a lot of them were built in the post-World War II period to accommodate the surge of motorization,” says Carlo Ratti, architect and engineer who directs the Senseable City Lab at Massachusetts Institute of Technology. “They are beginning to reach the end of their life.”
According to the 2022 American Road & Transportation Builders Association’s report, one in three U.S. bridges needs repair or replacement. The Department of Transportation (DOT) National Bridge Inventory (NBI) database reveals concerning numbers. Thirty-six percent of U.S. bridges need repair work and over 78,000 bridges should be replaced. More than 43,500 bridges are rated in poor condition and classified as “structurally deficient” – an alarming description. Yet, people drive over them 167.5 million times a day. The Pittsburgh bridge which collapsed in January this year—only hours before President Biden arrived to discuss the new infrastructure law—was on the “poor” rating list.
Assessing the structural integrity of a bridge is not an easy endeavor. Most of the time, these are visual inspections, Matarazzo explains. Engineers check cracks, rust and other signs of wear and tear. They also check for wildlife—birds which may build nests or even small animals that make homes inside the bridge structures, which can slowly chip at the structure. However, visual inspections may not tell the whole story. A more sophisticated and significantly more expensive inspection requires placing special sensors on the bridge that essentially listen to how the bridge vibrates.
“Some bridges can afford expensive sensors to do the job, but that comes at a very high cost—hundreds of thousands of dollars per bridge per year,” Ratti says.
We may think of bridges as immovable steel and concrete monoliths, but they naturally vibrate, oscillating slightly. That movement can be influenced by the traffic that passes over them, and even by wind. Bridges of different types vibrate differently—some have longer vibrational frequencies and others shorter ones. A good way to visualize this phenomenon is to place a ruler over the edge of a desk and flick it slightly. If the ruler protrudes far off the desk, it will vibrate slowly. But if you shorten the end that hangs off, it will vibrate much faster. It works similarly with bridges, except there are more factors at play, including not only the length, but also the design and the materials used.
The long suspension bridges such as the Golden Gate or Verrazano Narrows, which hang on a series of cables, are more flexible, and their vibration amplitudes are longer. The Golden Gate Bridge can vibrate at 0.106 Hertz, where one Hertz is one oscillation per second. “Think about standing on the bridge for about 10 seconds—that's how long it takes for it to move all the way up and all the way down in one oscillation,” Matarazzo says.
On the contrary, the concrete span bridges that rest on multiple columns like Brooklyn Bridge or Manhattan Bridge, are “stiffer” and have greater vibrational frequencies. A concrete bridge can have a frequency of 10 Hertz, moving 10 times in one second—like that shorter stretch of a ruler.
The special devices that can pick up and record these vibrations over time are called accelerometers. A network of these devices for each bridge can cost $20,000 to $50,000, and more—and require trained personnel to place them. The sensors also must stay on the bridge for some time to establish what’s a healthy vibrational baseline for a given bridge. Maintaining them adds to the cost. “Some bridges can afford expensive sensors to do the job, but that comes at a very high cost—hundreds of thousands of dollars per bridge per year,” Ratti says.
Making sense of the readouts they gather is another challenge, which requires a high level of technical expertise. “You generally need somebody, some type of expert capable of doing the analysis to translate that data into information,” says Matarazzo, which ticks up the price, so doing visual inspections often proves to be a more economical choice for state-level DOTs with tight budgets. “The existing systems work well, but have downsides,” Ratti says. The team thought the old method could use some modernizing.
Smartphones, which are carried by millions of people, contain dozens of sensors, including the accelerometers capable of picking up the bridges’ vibrations. That’s why Matarazzo and his colleague drove over the bridge 100 times—they were trying to pick up enough data. Timing it to rush hour supported that goal because traffic caused more “excitation,” Matarazzo explains. “Excitation is a big word we use when we talk about what drives the vibration,” he says. “When there's a lot of traffic, there's more excitation and more vibration.” They also collaborated with Uber, whose drivers made 72 trips across the bridge to gather data in different cars.
The next step was to clean the data from “noise”—various vibrations that weren’t relevant to the bridge but came from the cars themselves. “It could be jumps in speed, it could be potholes, it could be a bunch of other things," Matarazzo says. But as the team gathered more data, it became easier to tell the bridge vibrational frequencies from all others because the noises generated by cars, traffic and other things tend to “cancel out.”
The team specifically picked the Golden Gate bridge because the civil structural engineering community had studied it extensively over the years and collected a host of vibrational data, using traditional sensors. When the researchers compared their app-collected frequencies with those gathered by 240 accelerometers formerly placed on the Golden Gate, the results were the same—the data from the phones converged with that from the bridge’s sensors. The smartphone-collected data were just as good as those from industry devices.
The study authors estimate that officials could use crowdsourced data to make key improvements that would help new bridges to last about 14 years longer.
The team also tested their method on a different type of bridge—not a suspension one like the Golden Gate, but a concrete span bridge in Ciampino, Italy. There they compared 280 car trips over the bridge to the six sensors that had been placed on the bridge for seven months. The results were slightly less matching, but a larger volume of trips would fix the divergence, the researchers wrote in their study, titled Crowdsourcing bridge dynamic monitoring with smartphone vehicle trips, published last month in Nature Communications Engineering.
Although the smartphones proved effective, the app is not quite ready to be rolled out commercially for people to start using. “It is still a pilot version,” so there’s room for improvement, says Ratti, who co-authored the study. “But on a more optimistic note, it has really low barriers to entry—all you need is smartphones on cars—so that makes the system easy to reach a global audience.” And the study authors estimate that the use of crowdsourced data would result in a new bridge lasting about 14 years longer.
Matarazzo hopes that the app could be eventually accessible for your average citizen scientist to collect the data and supply it to their local transportation authorities. “I hope that this idea can spark a different type of relationship with infrastructure where people think about the data they're collecting as some type of contribution or investment into their communities,” he says. “So that they can help their own department of transportation, their own municipality to support that bridge and keep it maintained better, longer and safer.”
Lina Zeldovich has written about science, medicine and technology for Popular Science, Smithsonian, National Geographic, Scientific American, Reader’s Digest, the New York Times and other major national and international publications. A Columbia J-School alumna, she has won several awards for her stories, including the ASJA Crisis Coverage Award for Covid reporting, and has been a contributing editor at Nautilus Magazine. In 2021, Zeldovich released her first book, The Other Dark Matter, published by the University of Chicago Press, about the science and business of turning waste into wealth and health. You can find her on http://linazeldovich.com/ and @linazeldovich.
The Friday Five: Sugar could help catch cancer early
The Friday Five covers five stories in research that you may have missed this week. There are plenty of controversies and troubling ethical issues in science – and we get into many of them in our online magazine – but this news roundup focuses on scientific creativity and progress to give you a therapeutic dose of inspiration headed into the weekend.
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Here are the promising studies covered in this week's Friday Five:
- Catching cancer early could depend on sugar
- How to boost memory in a flash
- This is your brain on books
- A tiny sandwich cake could help the heart
- Meet the top banana for fighting Covid variants