Some 34 million semi trucks—also known as tractor-trailers or 18 wheelers—are currently in operation across the United States, hauling more than 10 billion tons of goods every year. In 2016 commercial trucks used 38.8 billion gallons of diesel fuel, at a cost of nearly $90 billion. And while trucking is a vital element in the national and world economy, according to the Environmental Protection Agency, medium- and heavy-duty trucks are also responsible for spewing 470 million tons of carbon dioxide into the atmosphere every year—a number that has nearly doubled over the last two decades.
But the era of noisy, polluting diesel trucks may soon be coming to an end, thanks to a team of engineers at Tesla who are working on a revolutionary new kind of big rig. The Tesla Semi will be able to travel as far as 500 miles on a single charge, consuming less than 2 kilowatt-hours per mile. That’s good news for the environment and a boon for trucking companies, which can expect to save as much as $100,000 per vehicle, per year, that they'd otherwise have spent on fuel. The Tesla Semi is also billed as the safest truck ever, with an “Enhanced Autopilot” system that helps avoid collisions. And instead of a roaring engine, it makes a quiet, spaceship-like sound as it revs from 0 to 60 miles per hour—fully loaded—in 20 seconds or less.
“This will have a huge impact on the economics of trucking,” says Joshua Resnick ’01, a senior engineer on Tesla’s semi team who has worked on the truck since the program’s inception in 2015 and designed the system architecture for its electronic controls. “There’s a ton of interest and a ton of people who have pre-ordered the vehicle.”
Building the world’s first all-electric semi truck is a challenge that makes sense for the electrical engineering alum, whose friends call him “the mad scientist.” In a career that has taken him from a basement lab in WPI’s Atwater Kent Laboratories, to a remote Alaskan fishing community, to the foothills outside America’s high-tech capital (Palo Alto), Resnick has spent his life tinkering with everything from fusion reactors to fishing boats. But building things is not his only passion. With a master’s in theology and experience working with at-risk youth, he is also driven by a mission to do good. And that, he says, is what makes Tesla the perfect fit.
“We’re a very ideological company,” he explains. “We're focused on transitioning the world to sustainable transportation, and it’s exciting to work at a company that’s on the leading edge. Because for me, what matters at the end of the day is, am I doing something that matters?”
Creative Freedom
When Resnick arrived at WPI in the fall of 1997, he was already an amateur engineer—he had spent his high school years avidly building and flying radio-controlled airplanes and helicopters, experimenting with the possibilities of flight. Once on campus, he immediately sought out the machine shop.

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“It was great, because I could just walk into the shop and make whatever I wanted,” he recalls. “I liked having that freedom and having all those good tools to work with. Even while I was taking my core classes, I had the opportunity to be creative on my own, and that's really where I thrive the most. I was just making stuff!”
Some of the stuff Resnick wound up making was far from ordinary.
“The Tesla coil got me in trouble with Campus Security,” he confesses. “My roommate and I were outside the dorm turning it on and making these giant electrical discharges—like, literally, I'm talking continuous eight-foot sparks. It's a pretty scary contraption and it makes a lot of noise—it sounds like a machine gun.”
Noticing the spectacle, a security officer stepped out of his car. While he couldn’t determine if the freshmen were technically breaking a rule, he told them the sparks needed to stop flying.
“I wonder if they added ‘no building Tesla coils’ to the campus rule book later,” he muses.
Other extracurricular projects received a better reception, like a tabletop nuclear fusion reactor, which earned him a mention in American Scientist magazine when he was a sophomore. Soon, faculty began to seek out Resnick’s help on their own research projects. Professor Alexander Emanuel offered him a disused lab space in the basement, complete with voltage generators and other power equipment. Professor David Cyganski asked for his assistance on a series of physics experiments, and their collaboration eventually led to an MQP that Cyganski still marvels over.
“The things he wanted to tackle were outside the realm of what many students might be interested in,” he says.
Resnick’s project investigated a phenomenon observed in prior radioactivity studies that seemed to violate the laws of physics. Believing the anomaly might be caused by environmental irregularities, he began with a commercial refrigerator, which he converted into an apparatus that controlled temperature to within 1/1,000 of a degree. After experimenting with temperature, air pressure, humidity, and other factors, Resnick and Cyganski were stunned to learn that the anomaly was caused by an error with a very commonly used sensor.