Electronic Design
The Plug Replaces The Pump

The Plug Replaces The Pump

After all the preproduction publicity, the first electric vehicles (EVs) and plug-in hybrid vehicles (PHEVs) from major automotive companies are now on the road—or possibly plugged into a nearby charging station. In addition, ongoing efforts to establish a charging infrastructure are underway.

While it may be early, there are a few lessons to be learned from the current status of these vehicles. With so little experience, industry researchers have modified vehicles to study and compile consumer reactions and determine how drivers cope with a major, lifestyle-changing transition of charging batteries versus pumping gas. Now it’s time for real-world feedback.

PEV Owner Reactions

Any significant change in buying habits is normally met with hesitation. This is especially true with a major purchase such as a vehicle costing $30,000 or more (see “GM Plant Shuts Down To Prepare For Volt Production Increase,” p. xx). While early adopters will tolerate more than typical consumers, their experience can shed light on acceptable and unacceptable attributes of the plug-in EV (PEV) ecosystem.

Charlie Yankitis, who lives in the Detroit area, has had a Chevy Volt for four weeks with a 240-V Voltec charging system installed in his home (Fig. 1). “I charge at home and I drive about 26 miles to work,” he says. “When I get to work, I am using a prototype of our charger. I am able to get to work on electric and home on electric.”

As the director of business development for SPX Service Solutions, the company chosen by General Motors to install the chargers for the Chevy Volt, Yankitis has a unique perspective. With chargers at both ends of his typical commute, he boasts using only five gallons of gas to travel 1000 miles (see “Test Driving The Chevy Volt” at www.engineeringTV.com).

“It’s quite an experience—better than I had expected,” says Yankitis. “The key is if you have a longer drive, you need to have charging available at your workplace.”

Other owners without ties to PEV companies are sharing their experience through the Linked-in Electric Vehicle Group and report similar satisfaction.

Dan Calderone of Phoenix, Ariz., has praise for the Nissan Leaf he is leasing (Fig. 2). After having it for one month, he drove 1300 miles on $19.25 worth of electricity. “We have settled into the routine of driving the Leaf and our new ‘normal’ is just that—normal,” he says. “We plug in at the end of a day and unplug before driving the car.”

Adjusting to a new driving and refueling (charging) lifestyle, Calderone knows how to avoid range anxiety.

“We have no range issues and no range anxiety,” says Calderone. “We understand the range limitations and the car does a great job keeping us informed about the remaining range.” He is satisfied that his Leaf performs perfectly for travel in the Phoenix metropolitan area. However, he has no plans to use the Leaf for road trips.

Calderone has first-hand experience with the performance of the vehicle’s electric motors and the impact of electrical loads. “I have seen the Leaf exceed its promised top speed of 90 mph effortlessly,” he says. “The AC appears to take about 20% off the range.”

With gas prices rising in 2011, the time is certainly right to have an EV. “I am very pleased to be driving at six-and-a-half cents per kW instead of $3.65 per gallon, but I feel that electric cars are great regardless of pump prices,” Calderone says.

Using the Leaf’s onboard charge programmer, Calderone programs the car to charge to 80% as soon as the rates drop. The 80% rate provides him a normal day of driving with about 30 miles to spare, and he minimizes the impact on the battery. Calderone thinks he may have to charge at 100% to cope with Phoenix’s summer weather but has yet to verify it.

The data is among the information obtained by Nissan and ECOtality, the charging system company. Without a Smart Grid, the data is transmitted to each company by two different techniques. Nissan gets its information though the Leaf’s onboard cellular system. ECOtality obtains its data though a Wi-Fi connection (see “Test Driving The Nissan Leaf” at www.engineeringTV.com).

As a satisfied EV owner, Calderone has identified one issue that Nissan may not have expected. “My new ‘range anxiety’ has to do with managing our lease miles,” he says. “So far we are putting 300 miles a month more than we should based on our lease terms.”

Phoenix does not have the 480-V Level 3 or dc fast-charging stations, but other regions of the country have installations for EVs. Charlie Allcock of Portland, Ore., has been able to take advantage of Level 3 charging.

“I love the dc quick charging experience,” he says. “There is a public dc quick charger here in Portland, and I’m getting four to five miles of range for every minute of charging, or 40 to 60 miles in the first 10 to 12 minutes.” The availability of the dc fast charger alleviates Allcock’s range anxiety on those days when he travels further than usual.

Allcock lives in a very flat area and drives about 70% at residential speeds and 30% freeway speeds. “My Leaf indicates that I averaged 4.3 miles/kWh last month,” he says “I drive in ECO mode almost all the time, but I don’t drive any different than I do in gas cars.”

Allcock leaves his house every morning with a full battery and a range of 100 miles in ECO mode in the Leaf. “On the days when I travel 60 to 70 miles, by mid-afternoon I usually quick charge for about 10 minutes and get about 50 miles more in range, which is usually enough for the rest of my afternoon and gets me home in the evening,” he says.

It appears at least among the early adopters, PEV users are readily making a transition from the pump mentality.

Car Companies Make The Transition

While these new owners are excited with their initial PEV experience, enticing the broader population to chuck the pump and charge ahead has several outstanding issues, not the least of which is cost. Car companies are addressing both the technical and business aspects of electrification and establishing a new eco structure. At the SAE 2011 World Congress, held April 12-14 in Detroit, Mich., several companies reported on their progress.

Looking forward to the time when PEVs could provide power to the grid, Minoru Sinohara, senior vice president of Nissan Motor Co. Ltd., shared Nissan’s vision of electric power flow connection to promote renewable energy. He says the connected EV with its batteries for energy storage is an important part of expanding renewable energy.

“The point here is a total energy management system utilizing all the information—information of the generation and the use of real-time demand, EV location and state of charge and so on,” says Sinohara. “All should be connected and managed.”

The GE Nissan Smart Grid Joint Research Program is accessing electric vehicle integration with the grid.

“This two-year program features benefit and risk assessment of EVs as a critical new substantial load for the Smart Grid,” says Sinuhara. As part of a smart community, research items will include battery deterioration and an EV data center that will evaluate the energy management system (Fig. 3).

Sherif Marakby, director of Electrification Programs & Engineering, SMT, Ford Motor Company, says that charging is the new experience that carmakers must address and value charging is the key to reducing the cost of charging. Collaborating with Microsoft, Ford’s customers use Microsoft’s Hohm software to automatically obtain the lowest charging rates without any additional programming or tracking.

As part of the combined Ford and Microsoft vision, Marakby identified the steps that the partners see toward Smart Grid integration (Fig. 4). “Last but not least is bidirectional powerflow with the grid,” he says.

Jay Iyengar, global director & chief engineer of electrified powertrain propulsion systems at Chrysler Group LLC, identifies bidirectional charging as one of the top five issues confronting electrification technology today that have to be addressed within the next five to 10 years. Allowing customers to provide energy back to the grid will give them greater value, she says.

Iyengar notes that a compact and efficient bidirectional charger of 6.6 kW ac, not necessarily high-power capability, with an efficiency of 90% or higher at full power and modular design to improve efficiency at lower power is essential for this to happen. In addition, bidirectional charging requires Smart Grid communication capabilities using the Smart Energy Profile (SEP 2.0).

Charging & Communicating

Among the new players that car manufacturers have to bring to the PEV future are suppliers of vehicle charging systems or electric vehicle supply equipment (EVSE). With companies such as SPX Service Solutions, Coulomb, ECOtality, AeroVironment, General Electric, and others providing leadership roles, the car companies have been able to introduce PEVs and give customers the energy they need to propel those vehicles.

Contracted to support home installations for the Chevy Volt, SPX Service Solutions started installing charging systems at the end of 2010. “To date, we’ve done hundreds of installations around the country,” says SPX’s Yankitis. SPX installs either the Voltec or the Coulomb Technologies charger and expects to use two other suppliers’ chargers that are not available yet.

The charger is connected to the DOE-supported (Department of Energy) EV Project, so it’s free to consumers as long as they authorize the sharing of the data. “That unit transmits over the cell network the data that the DOE is looking for on-vehicle charging,” says Yankitis. He thinks that the same kind of technology represents the future until the Smart Grid communications schemes are resolved.

Coulomb Technologies, a supplier of EVSEs for the Nissan Leaf, has both home Level 2 (240 V) and Level 3 chargers. Designed for the North American marketplace, Coulomb’s CT3000 family of dc fast-charge stations provides 50 kW charging for both indoor and outdoor applications (Fig. 5). The fast charger can charge a Nissan Leaf from 20% state of charge (SOC) to 80% SOC in less than 30 minutes.

Unlike the Level 2 charger approved in the SAE J1772 specification, the connector for the Level 3 charger is still being determined from several options. Japanese Carmakers, Tokyo Electric Power, and other Japanese technology companies developed the CHAdeMO (Charge de Move) connector and protocol. Coulomb uses this connector in its charging system, but it accommodates multiple connector types. In addition, the station allows remote, over-the-air software upgrades to handle potential transitions in the vehicle communications standard.

In addition to its Level 2 home chargers that are used for both the Leaf and the Volt, AeroVironment has a suite of 125-kW and 250-kW dc fast-charge stations (Fig. 6).

Utility Companies To The Rescue

Any hope of replacing the pump with electrical power requires replacing oil companies with electric utility companies. At the SAE 2011 Congress, Anthony Earley Jr., executive chairman of the board of DTE Energy, the electricity provider for the Detroit Three’s headquarters’ territory, provided his industry’s perspective.

“Electrification of the transportation system is one of the utility industry’s highest priorities,” says Earley. “Just about a year and a half ago, as chairman of the Edison Electric Institute, our trade association, I announced the adoption of an industry-wide pledge to support in every possible way the development of electric vehicles.”

DTE Energy is exploring three possibilities for end-of-life EV batteries: community energy storage systems, distributed solar and wind renewable sources, and replacement for existing substation backup batteries. This reuse of EV batteries could help reduce the total ownership cost of EV batteries as well as provide utilities with grid reliability and stability.

Also, DTE Energy has started to install Level 2 chargers in the homes of Chevy Volt owners in Southeastern Michigan. According to Haukur Asgeirsson, manager of engineering for power systems technologies at DTE Energy, the company has a special electric vehicle rate with a 40% discount after 11 p.m. until 9 a.m., Monday through Friday as well as holidays and weekends.

“Because it’s a special rate, we put a utility meter in the back of the house, a separate meter circuit, separate from the meter that is for the whole house,” says Asgeirsson.

The second meter allows DTE to track the consumption data for the charging station. In addition, it also allocates the time period when customers are charging to provide them with the discount when they charge at night. However, there currently is no communication to other devices even though DTE is installing smart meters as part of its Smart Grid infrastructure program. The main reason is security.

“Security is of great concern,” says Asgeirsson. “We don’t want to have a lot of openings into our IT network.” DTE Energy uses Itron OpenWay Network technology for its mesh network to collect the data.

The installation effort only started at the beginning of March, so there is insufficient data to draw any conclusions, according to Asgeirsson. “The consumer, the purchaser of the product coming off the line, is going to tell us how they charge,” he says. “All of these other studies are fine but we don’t know how they are going to behave until they start buying in mass.” Asgeirsson expects that by mid-summer or the end of the year, DTE Energy will start seeing some real results.

The utility industry, and specifically DTE Energy, is actively seeking answers to technical and business questions through several projects. “We are excited about being at the forefront not only of this battery research but also a wide-ranging set of pilot programs to understand and remove the barriers to wide-spread deployment of EVs,” says Earley. “We believe that the utility industry can play an important role both in helping to build and support the infrastructure for EVs and leveraging battery technology to enhance energy storage capabilities.”

The interactions between utility companies, the Smart Grid, and PEVs are extremely complicated and seem to make supplying gasoline to vehicles appear almost trivial. As part of the Smart Grid Interoperability Panel, the U.S. National Institute of Standards and Technology (NIST) is actively studying the impact. In the report Electrical Transportation, extensive analysis of use cases for PEVs supplying power to the grid identifies 15 interfaces (Fig. 7). The project’s goal is basic infrastructure implementation in time to support a million PEVs by 2015.

Charging Ahead

For vehicles and their owners to avoid the pump, they must make new friends with the plug. To get into significant volumes beyond the enthusiasts and early adapters, several changes need to occur in the vehicles as well as in the infrastructure.

Carmakers and suppliers, including battery makers that have the biggest challenge, continue to make progress in many areas. However, utility companies have several issues to resolve as well. What’s needed now is continued collaboration in R&D and standards to reduce cost and make PEVs viable for mainstream personal transportation.

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