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Exclusive: 3-Wheeled Aptera Reboots as World’s Most Efficient Electric Car

1,600 km per charge promised by the team that created a lightweight two-seat EV a decade ago

7 min read
Rendering of the new vision for the Aptera electric car.
The shape of the reborn Aptera electric car is familiar to some, but every detail has been improved to boost efficiency even further.
Illustration: Aptera

A decade is a very long time in electric cars, so the name Aptera may be unfamiliar to many. But those who saw or drove the original prototype of the world’s most energy-efficient vehicle will likely never forget it.

A body shaped like an airplane fuselage supported by only three wheels, and the promise of 160 kilometers (100 miles) of range for just a few pennies worth of electricity—these features made the Aptera unlike any other vehicle. It lured passionate fans, just as Tesla has through the years.

But Aptera liquidated in December 2011, and its founders moved on to other ventures. Now, they’ve quietly come back together, reacquired the defunct company’s intellectual property, and are preparing to launch Aptera once more.

Ten years later, the car—if successfully brought to market—would still be the most efficient EV on the road. Except this time, Aptera plans to offer the world’s first electric car with 1,600 km (1,000 miles) of range—which would represent a stunning advance over the 600-km range offered by today’s best-performing commercial EVs.

IEEE Spectrum spoke to three of the original Apterans: Chris Anthony, Steve Fambro, and Michael Johnson. Anthony and Fambro are now CEOs of the new Aptera, while Johnson is listed in company presentations simply as cofounder.

The trio reunited to pursue the goal they never gave up: to build the world’s most efficient electric vehicle to offer practical transport while using minimal energy. Today, they speak confidently of a refined design, which they say incorporates a decade of advances in computational fluid dynamics, additive metal manufacturing, and global electric-vehicle components.

It’s still very early days for the group, which is operating with seed capital in the low six figures and doesn’t yet have a single prototype on the road. But they feel it’s time to go public with their plans for Aptera redux, and expect that sharing them will help shake loose the funding they need to build their first prototypes and offer the public something to see and drive.

A Missed Opportunity

When bankruptcy forced Aptera’s founders to abandon their original business, they expected larger, well-capitalized automakers to step in and pursue greater efficiencies in every aspect of EV design. “What astonishes me,” Anthony said, “is that none of them have yet taken up the challenge: How efficient can a car be?”

The best attempt might have been the BMW i3, the Bavarian maker’s 2013 compact electric hatchback. With a body shell made of carbon-fiber-reinforced plastic, an aluminum rolling platform, an optional two-cylinder range-extending engine, and 112 to 129 km (70 to 80 miles) of range, the i3 ruled the energy-efficiency charts for a few years.

Still, by model year 2020, the i3 and its ultra-efficient construction looks to be an evolutionary dead end. Electric cars arriving over the next five years will be hatchbacks, utility vehicles, and luxury sedans that look pretty much like current ones. And they’ll be heavier than their gasoline counterparts—at 2,500 kilograms or more—due to the weight of battery packs with the 60 to 100 kilowatt-hours required to give them a range of 320 km (200 miles) or more. Plummeting cell costs have made these big packs possible earlier than projected a decade ago.

Aptera plans to offer a range of battery capacities, from 40 to 100 kWh. The largest pack, however, will provide that 1,600 km (1,000 miles) of range, equating to energy usage of less than 100 watt-hours per mile. In contrast, Tesla’s most efficient 2019 car, the Model 3 Standard Range Plus, is rated by the U.S. EPA at 250 watt-hours per mile.

Achieving those stunning numbers is all about cheating drag and reducing mass. The 60-kWh Aptera, the team said, will weigh about 800 kg (1,800 pounds). The most efficient four-seat Nissan Leaf Plus, with a 62-kWh battery, weighs twice that—1,557 kg (or 3,433 pounds)—and is EPA-rated at one-third the efficiency, at 310 watt-hours per mile.

Nuts and Bolts

The body shell is made of simple resin-infused sandwich-core composite sections bonded together, both lighter and less costly than steel or aluminum.The body shell is made of simple resin-infused sandwich-core composite sections bonded together, both lighter and less costly than steel or aluminum.Illustration: Aptera

So how do they do it? The Aptera’s structure is made of resin-infused sandwich-core plastic composites. That avoids both the weight of steel or aluminum, and the tens or hundreds of millions of dollars required to stamp out those parts in volume.

As for safety—top of mind in a small, odd-looking two-seat vehicle—the company claims its composite passenger cell will be “stronger than that of any other vehicle on the road today.” Aptera plans to have prototypes of its vehicle fully crash-tested as soon as they’re built, just like any four-wheeled light-duty passenger vehicle.

Advances in computational fluid dynamics enabled designers to run simulations in two to three hours that would have taken four days a decade ago. The resulting evolution of the body shape is crisper, with a sleek, stark interior that carries over nothing from the planned Aptera 2e of 2009.

Aptera's engineers plan to evaluate the effects of using two wheel motors against three; virtually everything else up front is power electronics.Aptera's engineers plan to evaluate the effects of using two wheel motors against three; virtually everything else up front is power electronics.Illustration: Aptera

The battery remains located on the cabin floor, tilted up at its back end as the cabin tapers. Regardless of capacity, the pack will be liquid cooled, though not with the conventional radiators and pumps used by most EVs. Instead—and the team was very vague on this point, referring to pending patents—the cooling is achieved, somehow, via the body surface. (Stay tuned on that one.)

Advances in structural design software allied with additive metal manufacturing let Aptera reduce weight substantially in complex metal parts.Advances in structural design software allied with additive metal manufacturing let Aptera reduce weight substantially in complex metal parts.Illustration: Aptera

Additive manufacturing will allow Aptera to create complex structural parts with a “bonelike” pattern that can easily be metal-printed in low numbers. Rather than a milled or forged aluminum casting, the much lighter part can be printed on site.

This time, Aptera expects to use 50-kilowatt (67-horsepower) wheel motors from an Eastern European supplier. It will test the efficiency and performance effects of powering just the two front wheels, but expects to launch with all three wheels powered. Total power of 150 kilowatts in a car this light, Fambro pointed out, means that acceleration is limited solely by the adhesion of the tires. Performance model ahead, perhaps? (It certainly worked for Tesla.)

For power electronics, charging ports, cabling, and the host of other needed EV components, the Apterans say they can buy off the shelf as needed, and spend their efforts where it counts: cutting weight and reducing drag.

A Second Chance

Anthony and Johnson are cofounders of Flux Power, an industrial battery technology company that has kept them deeply involved in lithium-ion cell production. After the collapse of Aptera, Anthony served as CEO, and Johnson as a director and investor, for Flux Power. Fambro, meanwhile, entered organic farming, set up global distribution deals, and became a venture partner.

This schematic for the interior shares almost nothing with the decade-old version, reflecting advances in touchscreens and digital controls.This schematic for the interior shares almost nothing with the decade-old version, reflecting advances in touch screens and digital controls.Illustration: Aptera

The Aptera dream never left any of them, though. When it became possible to reacquire the startup’s intellectual property, they did so. What has stunned them since, they agreed, is the enthusiasm of many of their former staff, partners, and even vendors.

Despite its ending, the Aptera experience left the team with mostly positive memories, Anthony said. “We’ve had people volunteer to come back and work for equity, not cash,” he marveled, “just to be a part of it.”

A few years ago, U.S. Securities & Exchange Commission rules went into effect that permitted “crowd-funding investments” by interested individuals without going through the rigorous disclosure and documentation requirements the SEC places on larger funders.

Aptera expects small investments—from EV supporters, previous reservation holders, and those newly inspired by their vision—to provide its first infusion of capital. The company is also in talks with traditional equity and venture investors, Anthony said. Aptera hopes to get to the $2.5 million that will allow it to build three running prototypes by the end of this year and reveal them to the public in 2020. 

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The original Aptera received purchase deposits from 4,400 Californians. It could have gone as high as 20,000 reservations globally, Anthony suggested, if it hadn’t decided to limit deposits to residents of its home state.

The reconstituted company is still far from accepting deposits, since it doesn’t yet even have a running prototype. But any crowd-funding investor who puts in $1,000 or more gets a slot on the reservation list. Aptera doesn’t plan to start accepting pre-orders until it can guarantee a delivery date to each purchaser.

While the team mentions plans for a six-seat Aptera to serve as a fully autonomous shuttle, their task right now is clear: Raise enough money to launch final design, development, and production engineering so the company can start delivering a better version of the car it originally planned to build back in 2009.

Aptera execs are very clear that they’re not trying to be Tesla—and that their two-seat, three-wheeled vehicle will likely never reach the volumes of a Tesla Model 3. That’s okay with them, because they still see a niche market for ultimate efficiency that has stayed wide open for the 10 years they were gone.

“We’re excited,” Anthony concluded. “The people are ready to come back, we still think this is something the market and the world needs, and we’re ready for it. And that’s even before there’s any money!”

This article was updated on 29 August 2019 to reflect that Aptera closed in 2011 after liquidation, not bankruptcy.

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