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Topping off the EV Tank


Like any consumer electronics product, a car powered solely by electricity will work only as long as there’s juice in its battery, and most “battery electric vehicles,” or BEVs, sold to-date have typically provided less than 100 miles of range on a full charge.

So, to help buyers overcome “range anxiety”—concern about running out of power in the middle of a commute, for example—automakers have stressed ways to top-off the proverbial tank: offering a variety of home charging stations and working to boost the number of commercial charging venues nationwide.

ow, innovations in both vehicles and chargers are affecting change. An emergent class of affordably priced long-rangeBEVs promises to greatly reduce range anxiety, while advances in charging technology are making home chargers better than ever and may even spur new publicly available options.

But as usual, some hurdles remain.

“What we’re seeing now is the potential for battery vehicles that [yield a] 200 mile range and that are affordable to a large segment of the population, so I think we’re going to be seeing a shift in what the market demands for charging, and what consumers are really going to want,” says Lisa Jerram, principal research analyst at Navigant Research in Washington, D.C. With a 200-mile-capable BEV, there will be less call for unplanned charging at public stations and “most people will charge at home most of the time,” she says. Yet, these longer-range EVs will mean a greater demand for faster charging technologies at public facilities along highway routes—the kinds of technologies and facilities that automakers are now working to promote, Jerram adds.

According to projections released by Navigant in January, some 65,000 commercial chargers were in place in the U.S. at the end of last year. By 2020, Navigant forecasts growth to more than 300,000 commercial chargers nationwide. The fi gure comprises all types of commercial chargers, including those at workplaces, public charging stations, fleet vehicle depots, and locations such as hotels or airports.

U.S. Department of Energy statistics peg the number of electric fueling stations nationwide at 30,945 last year, up from 25,602 in 2014 and 19,410 in 2013.

The most staggering increase in U.S. electric fueling stations was in 2011, when there were 3,394, up from just 541 nationwide in 2010, the DoE data shows. It was in late 2010 that General Motors introduced the model-year 2011 Chevrolet Volt, the first mass-market plug-in hybrid electric vehicle, jolting the market for modern EVs.

From Rails to Pads

“Going back to the 1910s when briefly there were more electrics in this country than petrol engines, the original plans called for rails and perhaps overhead wire” to recharge cars while they were parked, notes Richard Doherty, research director at The Envisioneering Group in Seaford, NY.

Then, after World War One, gasoline-powered cars supplanted electrics until the 1950s when EVs such as the Renault Dauphine-based Henney Kilowatt debuted in the U.S. However, “there were hundreds of electric cars for sale in the 1950s, compared to thousands and thousands before World War One,” Doherty says.

But the true impetus for today’s EVs was in the mid-1990s, he recalls, when the inventor of the nickel metal hydride (NiMH) battery, Stanford Ovshinsky, created a prototype electric car of his own. “I remember getting into a lower-end Toyota converted to electric and this thing took off like ludicrous mode in a Tesla,” he says.

Ovshinsky’s prototype vehicle helped prove the viability of NiMH batteries for EVs and inspired Toyota and Honda to pursue electric and hybridelectric cars, Doherty contends. It also served a secondary purpose he says: promoting the use of solar cells made by Ovshinsky’s company, Energy Conversion Devices Inc., for charging electric vehicles.

At the same time, researchers at the Society of Automotive Engineers (SAE) began developing other ways to charge EVs, including a push into wireless charging through technology embedded in streets—mainly as a way to recharge electric city buses in their dedicated lanes, Doherty notes.
Now, he adds, the focus has moved to “on-the-fly charging” technologies for EV-owning citizens and ways to reduce recharge time to mere minutes instead of hours. He expects municipal and regional trials of wireless charging technologies to commence before 2020, and widespread adoption to come around 2030, with Europe, Japan and Scandinavia leading the way rather than the U.S. As evidence that wireless charging is nearing fruition, Doherty points to a reduction in SAE papers on the technology, which he says signals that manufacturers are keeping their latest developments private.

Still, one should “never underestimate the powers of inertia and regulatory zeal and keeping the bottom line near what the costs are for running a vehicle as the electric highway gets closer,” Doherty warns.

A report in 2014 by Navigant Research projected that wireless could be the leading method for charging EVs by the middle of the next decade. The report figures that equipment for light duty vehicles—such as passenger cars—will reach annual sales of just under 302,000 units in 2022, reflecting a compound annual growth rate (CAGR) of 108 percent from 2013.

Much of that growth may come from wireless charging at home, rather than from public charging.

“Perhaps as you get these 200-mile EVs in the heart of the market—where the average transaction price is $34,000-$35,000—the owners of those cars are not going to be clamoring as much for charging infrastructure,” says Sam Abuelsamid, senior research analyst at Navigant Research in Boulder, CO. “That also opens up an opportunity for wireless charging at home,” boosting the convenience of at-home top-offs.

Nevertheless, “one of the issues with wireless charging is the technology is still relatively in its infancy,” Abuelsamid says. Although an SAE standard named J2954 is in development, it has not been fi nalized, while the SAE standard for different types of wired EV charging (named J1772) are well entrenched. More, “right now there are no OEM [automaker] solutions for wireless charging, and it will probably be at least another three to five years before we see any OEMs offering that” along with interoperability (letting any wireless charger work with any EV), he notes.

There is an aftermarket wireless charging system available today for just a few EVs, from Evatran Group Inc., based in Richmond, VA—and according to Steve Cummings, senior manager of brand and marketing strategy, Evatran so far is alone in the consumer-oriented wireless EV charging market. Its product sold under the brand name Plugless, comes in versions for the Chevy Volt ($1,260), Nissan Leaf ($1,540) and Cadillac ELR ($1,940). It’s composed of three parts: a control panel installed on the garage wall, which is connected to an inductive coil “parking pad” that sits on the garage fl oor, and a “vehicle adapter” fixed to the bottom of the EV that receives the energy from the pad and transmits it to the vehicle’s built-in J1772 charger. It does this over a 100 millimeter (slightly less than four-inch) gap between the pad and the receiver. Of course, the vehicle must be parked in exactly the right position over the pad for the power to be transmitted most effi ciently, and even then there is a 12 percent effi ciency loss versus a comparable, 3.3 kilowatts (kW) “Level 2” wired charging system, Cummings says. By Evatran’s calculation, this would cost a Volt driver an extra 33 cents per evening charge based on an average electricity price of 13 cents per kilowatt hour.

The Plugless Level 2 EV charging system for those vehicles debuted in 2014. This year, Evatran will add a 6.6kW system for the Tesla Model S, and another 3.3kW system for the BMW i3, Cummings says.

“Largely why some of the OEMs are waiting for a standard is because it will allow wireless EV charging to integrate directly into the battery in a way that is cost-effective, across all car manufacturers,” he adds, noting that Evatran participates in the SAE J2954 committee.

What Automakers are Doing Today and for Tomorrow

To be sure, automakers are innovating in both the wired and wireless charging spaces, in many cases through collaborative efforts.

In early 2014, for example, Audi set up Audi ONE, an internal organization tasked with researching and developing new products, charging infrastructure and ways to market EVs to consumers. The work ties into Audi’s stated goal that 25 percent of its vehicle offerings should be plug-in vehicles by 2025—including a PHEV version of its flagship A8 sedan and an all-new BEV crossover utility vehicle (CUV) that is scheduled to launch in late 2018 with a range of 250 miles.

“This is in large part evolving our business to support electric. It’s a new powertrain strategy that will become increasingly pervasive,” says Wayne Killan, electric vehicle architect at Audi ONE in Herndon, VA.

To support that evolution, by 2018 Audi will provide a nationwide network of “fast charging” stations along U.S. highways. Further, the equipment will be rated at 150kW, which is three times more powerful than the standard DC fast chargers today, and even more powerful than the 135kW fast chargers provided by Tesla’s charging station network, Killan says. These Audi chargers can replenish the new BEV CUV to 80 percent of its battery capacity within 30 minutes, he says.

But Audi will not build this network alone, Killan says. Talks with other automakers have been ongoing for about a year, he explains, adding a network of 200 to 400 charging stations, each with multiple chargers available, will be created over two to three years.

An obstacle is how to tie this new network and existing networks together so that users can recharge anywhere but have the bill sent to only one account. To that end, Audi is one of the founders of the ROEV Association, a trade group announced last November whose stated mission is to “increase the appeal of EVs by enabling charging network interoperability in the U.S.” Others include BMW, Nissan, and the largest charging network operators today—Blink, ChargePoint and EVgo.

BMW is building its own urban metropolitan charging infrastructure in collaboration with Nissan, Volkswagen and charger network operators, as well. A partnership with VW and ChargePoint announced at the Washington Auto Show in January 2015 was aimed at building 100 charging stations along the Boston-Washington, D.C. and Portland, OR through San Diego, CA corridors; and by the end of last year, 59 of those stations were in place, says Cliff Fietzek, manager of connected e-mobility at BMW of North America in Woodcliff Lake, NJ. Separately, BMW teamed with EVgo to install 100 more DC chargers at stations in California—with a commitment for an additional 500 by early 2018. And an alliance with Nissan installed 95 fast chargers in Detroit by the end of last year, out of a committed 120. These incorporate both the CCS (Combined Charging System with DC and Level 2) technology favored by BMW, and Chademo, a type of DC fast charging technology favored by the Japanese automaker.

The ChargePoint and EVgo projects cover 80 percent of BMWs EV customer base, and the Nissan project covers the remaining 20 percent, Fietzek says. But this won’t be sufficient in the final analysis, he adds. “The next iteration will be increasing the power level of the chargers,” like Audi and Porsche are planning, he says.

Automakers began working on 300kW DC fast chargers about six months ago, and the SAE is now embarking on a revision of the J1772 standard to boost DC fast charging to 300kW, Fietzek notes.

Porsche recently announced its Mission E Concept car that will lead to a production vehicle in 2020, says Calvin Kim, a spokesman for Porsche Cars North America in Atlanta, GA. It’s expected to have a 300kW DC fast charging system that will bring the car to 80 percent charge in 15 minutes.

Wireless charging is on automakers’ agendas also—and they won’t necessarily wait for an SAE standard to emerge before bringing cars to market. Porsche is developing both a wireless charging system and an 800 volt battery for the car, Kim says. And BMW is already in “series development” with a wireless charging system for a next-generation PHEV, Fietzek says.

When they do come out with their wireless charging offers, most automakers will use a 3.5kW system, Fietzek predicts. But there’s the possibility of 7kW wireless charging coming to the U.S., and 11kW wireless charging coming to Europe, too, he says.

“The reality is it’s the use case” that matters, concludes Pamela Fletcher, executive chief engineer for electrified vehicles at GM in Warren, MI. “There are some people who are more worried about the convenience, there are some who are more worried about the efficiency and the energy consumption, and those people have two different needs and requirements around charging.”

When all is worked out technologically,one contstant will remain: inconstancy. “Charging,” Fletcher delcares, “will not be one size fits all.

Robert E. Calem

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