The future is electric. Caltech faculty members, students, and alumni have known it for generations, which is why electric vehicles have been a focus of research for the Caltech community for decades.

Climate consciousness, rising fuel prices, and government subsidies may help account for the rising popularity of EVs in the United States. But without technology dreamed up and developed by a few key individuals at the Institute, the 5.6 million EVs on the road worldwide may never have been built.

Several Caltech alumni who were major figures behind the EV revolution were interviewed recently by David Zierler, director of the Caltech Heritage Project. Unless otherwise noted, all quotes in the story below are taken from these interviews, which will be available on the Caltech Heritage Project website in late 2022.

In the United States, transportation accounts for 29 percent of all greenhouse gas emissions—more than the amount from electricity production or industry. Locally, the impact of those emissions created, for many decades, a defining feature of Los Angeles: its perennial smog problem.

The discovery of what caused LA's smoggy skies was the result of a collaboration between of two prominent members of the Caltech community during the 1940s: chemist, inventor, and alumnus Arnold Beckman (PhD '28) and Arie Haagen-Smit, professor of bio-organic chemistry. In 1950, Beckman and the recently established Los Angeles County Air Pollution Control District (LACAPCD) set up a lab for Haagen-Smit, who found that smog arose from hydrocarbons produced by the combustion of gasoline, together with oxides of nitrogen. When energized—as by LA's abundant sunlight—the two chemicals give rise to ozone and the aerosols that comprise smog. Haagen-Smit became the founding chairman of the California Air Resources Board (CARB), and was known as the "father of air pollution control." His work directly led to the development of pollution control systems starting in the 1960s.

As we know now, those smog-producing byproducts of internal combustion engine-driven vehicles not only harm human health directly, they also trap the sun's energy in Earth's atmosphere, driving climate change and its disastrous effects. Our addiction to cars is having a measurable negative impact on the world. But in the 1960s, as now, cars were an integral aspect of daily life—so the next generation of Caltech researchers turned their attention to reducing the pollution they generate. That pivot led to electric vehicles.

Electric vehicles (EVs)—which run off power stored in batteries as opposed to power generated directly by burning fossil fuels—have existed since the late 1800s. Yet the popularity of the gasoline-burning Model T in the early 1900s coupled with the availability of cheap gas and a lack of understanding about the effects of fossil fuels on the environment effectively killed the technology for decades.

Wally Rippel (BS '68) remembers developing an interest in electric vehicles while discussing the issue of air quality in a Caltech classroom on a smoggy LA day during the '60s.

"The question was, so what could General Motors do? What could the federal government do? What should the state of California be doing?" Rippel says. Ultimately, rather than rely on corporations or the government, Rippel realized that Techers like himself could do a lot to foster change.

Rippel spoke with Haagen-Smit to learn more about smog and what could be done to combat it. At that time, he recalls, "Dr. Haagen-Smit was in his prime here at Caltech doing research. He had already established that roughly 80 percent of the smog in the greater Los Angeles area was due to automobiles. There was a lot of controversy about that. The car companies didn't like that, and it was a challenge for Caltech dealing with that," he says.

The issue of smog alone did not necessarily make the case for electric cars, Rippel notes, since the generation of electricity to power the cars also contributed to smog. The decision to move toward electric cars instead would depend on how much extra burden electric cars would place on the power grid. To determine those impacts, Rippel set out to estimate the amount of energy needed to propel a vehicle and gauge how efficient batteries, chargers, and motors would need to be. Ultimately, he calculated that electrifying every car and truck in LA would only require a 20 percent increase in electricity generation.

"That was my aha moment," Rippel says. "I realized that from an emissions point of view, electric cars made sense."

In 1968, Rippel challenged MIT to a race to see which institution could develop the fastest and most reliable all-electric vehicle. The Caltech team equipped a 1958 Volkswagen bus to run on electric power. They loaded the boxy vehicle's ample interior with 2,000 pounds of lead-acid batteries and drove to Cambridge, Massachusetts. Meanwhile, the MIT team fielded an electrified 1968 Corvair and took off for Pasadena. The team that reached the other team's campus first would be declared the winner. After about a week and a half on the road, the MIT team "won" when it was towed across the finish line 37 hours and 20 minutes before the Caltech team made it to Cambridge. However, the MIT team had accrued significant penalty time because their Corvair needed multiple tows, was recharged with a portable generator between official charging stations, and required replacement parts. Caltech's ''Voltswagon'' made the entire trip on its own steam, so—after calculating out all of the penalties—the judges from Motor Design magazine declared it the winner.

The fact that the Voltswagon never needed to be towed was "kind of a badge of honor," Rippel says. "We wanted to be the first electric car to cross the country fully on electric power, and we did, with the exception of a few feet where we pushed the car when we were working on the motor thing. But other than those few feet, it was all electric power."

Victor Wouk (PhD '42), strongly supported the Caltech-MIT electric race, which occurred at the same time as his first experiments to create hybrid cars that relied on both gasoline and battery power. Wouk's thesis research at Caltech examined the potential of fires and explosions that could result from the generation of static electricity during gasoline distribution, and it was at Caltech that that he first came across the idea of regenerative braking as a power source for vehicles. In the early 1970s, following his efforts to prototype an electric car, Wouk successfully retrofitted a Buick Skylark as a gas-EV hybrid, which demonstrated the viability of a technology that would later be mass produced by Toyota and other manufacturers.

After graduation, Rippel continued to promote and advance the field of electric vehicles. In the 1980s, together with over a dozen other Caltech alums, including Alan Cocconi (BS '80), Rippel consulted for AeroVironment Inc. in the development of General Motors' Sunraycer, a solar-powered vehicle designed to compete in the 1987 World Solar Challenge, a five-day race across Australia using solar-powered vehicles.

AeroVironment founder and Caltech alumnus Paul MacCready (MS '48, PhD '52) tapped Alec Brooks (MS '77, PhD '81) to work with Howard Wilson, a senior executive at Hughes Aircraft company and project manager for GM's SunRaycer team. MacCready was dedicated to the creation of efficient transportation methods, and his Gossamer Condor aircraft won the Kremer Prize for the first human-powered flight (over a half mile course, surmounting a 10-foot hurdle at the beginning and end of the course) in 1977.

As MacCready said in a 1998 TED Talk, "The message from all these vehicles is that ideas and technology can be harnessed to produce remarkable gains in doing more with less; gains that can help us attain a desirable balance between technology and nature. The stakes are high as we speed toward a challenging future."

The Sunraycer team was led by one of MacCready's chief engineers at AeroVironment, fellow alumnus Alec Brooks. After aerodynamic tests that confirmed the final body designs, which were performed at Caltech's 10-foot wind tunnel, the final lens-like Sunraycer shape was decided.

The Sunraycer team wound up winning the World Solar Challenge by a significant margin, finishing the race two days ahead of its nearest competitor. Although impressed by their success, GM was not initially thinking about developing an EV prototype. At this time, Brooks and Wilson laid the groundwork at GM to build support for an EV program. Meanwhile, Alan Cocconi, who was working as a consultant to Aerovironment, figured out key components of an EV drive system. In 1988, nine months after the Sunraycer's Australian victory, and with Howard Wilson and Hughes Aircraft serving as the interface between GM and Aerovironment, GM approved the construction of the General Motors Impact (which would eventually become General Motors EV1, which was profiled in the 2006 documentary Who Killed the Electric Car?).

Consulting for AeroVironment, Cocconi designed and built the controller used in the Impact. During testing of the completed Impact, Cocconi noted GM's reluctance to embrace the new technology.

"An example is when we were at the test track filming the promotional video for the auto show ... we had a license plate on the car that said, 'The future is electric,' which we thought was appropriate for a promotional video," Cocconi says. "But we were at the GM test track with their film crew, and the PR head came along and said, 'That's too strong a statement. It has to go.' They replaced it with a generic dealer license plate."

The EV1 was the first modern mass-produced electric vehicle, but only lasted from 1996 to 1999. A majority of the cars manufactured—which were leased, not sold, to customers—were returned and then crushed.

In 1992, Cocconi and Rippel co-founded AC Propulsion Inc. with Paul Carosa, formerly of Hughes Aircraft Company. AC Propulsion developed the tzero, an electric sports car that originally produced 200 horsepower using lead-acid batteries. It was later converted to use lithium-ion batteries. This version of the tzero was light and quick, capable of accelerating from 0 to 60 miles per hour in just 3.6 seconds, on par with today's Porsche 911. In early 1999, Brooks left Aerovironment to lead the tzero production program at AC Propulsion. As a way to garner interest in the project, Brooks was part of an effort to invite rich tech elites to pit their gas-powered supercars against the tzero in drag races at Moffett Federal Airfield near Mountain View, California.

The tzero drag races a Ferrari

"We had some people come out. One was Andy Rubin, who was the original developer of Android. He came out with his Ferrari," Brooks says. "Some other people came out with some pretty hot cars. We set up a one-eighth mile drag strip on the taxiway ... the tzero beat them all. …We won."

It was around that time that Tesla Inc. co-founder Martin Eberhard drove the tzero and encouraged the AC Propulsion team to mass produce it. (When AC Propulsion declined in order to focus on other projects, Eberhard and engineer Marc Tarpenning instead launched Tesla, which currently sells about 13.9 percent of all electric vehicles worldwide.)

AC Propulsion remains one of the reasons that EVs have been adopted widely the United States.

"I think our interest was in making electric vehicles happen," says Dave Sivertsen (BS '80, PhD '89), who served as vice president of technology at AC Propulsion for 19 years and is now science content and technology manager at The Huntington. "As a small company, it's real hard to build a vehicle from the ground up. Some of our efforts were actually devoted to developing the market."

AC Propulsion went to the California Air Resources Board and testified about the potential for EVs, and also built test vehicles for Southern California's South Coast Air Quality Management District. "You had to get people used to the fact that electric vehicles were not just a fantasy, that you could really make something that took care of a niche in the market," Sivertsen says.

AC Propulsion continues to manufacture EV drivetrains that can be retrofitted for existing car models. Rippel, who joined Tesla in 2006, left the company in 2008, roughly when the Tesla Roadster began production. He continues, however, to be involved in EV technology. Meanwhile, interest in electric vehicles at Caltech continues today. Caltech students have participated in the Formula E electric vehicle race, for example, while faculty members pursue research on topics ranging from advanced battery technologies to smart EV charging facilities.

Although his career was devoted to EVs, Rippel cautions against failing to explore all potential alternatives. "I never want to feel that we are locked into a solution," he says. "It could be tomorrow that we'll have a breakthrough that will obsolete electric vehicles. If that happens, that's wonderful. ...The only thing I want to see, though, is that rather than just knowledge, that people learn thinking skills. It's good to know things, but it's better to be able to think well. …It's something that I deeply value [about] the Caltech experience; [it] is not so much what you learn, but how you learn to think. I hope that Caltech never loses that."