V2G-capable electric Scion Xb belonging to Mid-Atlantic  Grid Interactive Car Consortium can share its electric energy with the local grid if needed.
V2G-capable electric Scion Xb belonging to the Mid-Atlantic Grid Interactive Car Consortium can share its electric energy with the local grid if needed. Conversion based on AC Propulsion electric drive system.

Electrification Roadmap Bypasses Important Role for Vehicle-to-Grid


By Steven Letendre

On November 17, EVWorld's Bill Moore provided an excellent overview of an exciting new plan proposed by the Electrification Coalition, a group of top executives from 13 companies including smart grid solutions provider GridPoint Incorporated and one of the nation's largest investor owned utilities Pacific Gas & Electric Corporation. The Coalition's report Electrification Roadmap: Revolutionizing Transportation and Achieving Energy Security, which was released on November 16, establishes a national goal to meet 75 percent of light duty vehicle miles traveled with electricity by 2040. To meet this goal some 200 million GEVs (grid enabled vehicles) would eventually need to be introduced onto the nation's roads and highways.

The Coalition's report does an excellent job of making the case for this ambitious goal based on the petroleum displacement potential and the associated economic and national security benefits, in addition to addressing the significant challenges. However, the report falls short in my opinion by discounting the key role that vehicle-to-grid (V2G) technology could play in helping to meet the 2040 goal. V2G systems allow advanced electric drive vehicles to become fully integrated elements of the power system providing valuable grid support services. The revenue potential from providing these services is significant, and could serve to overcome the higher cost of GEVs.

Section 2.4.5 of the Electrification Roadmap acknowledges that vehicle-to-home and vehicle-to-grid technologies offer promise for the future, but that mass deployment of the technology is not likely until the third or fourth generation of GEVs. The report briefly touches on three issues to support this conclusion.

First, the report state that prior to deployment of V2G applications, homeowners or the automakers would have to install bidirectional chargers. In my judgment this requirement does not relegate V2G deployment to some distant future. A pilot V2G demonstration underway by the Mid-Atlantic Grid Interactive Car Consortium (MAGICC) uses onboard charging technology from AC Propulsion Incorporated that allows bi-directional power flows to and from the vehicle and the grid. This technology has been proven to be safe and reliable for several years. Alternatively, some vehicle charging station developers have stated plans to integrate V2G functionality into their products. Coulomb Technologies, one of the Electrification Coalition members, states in its product specification sheets that one of the benefits of its technology is, “Smart Grid integration for utility load management with future V2G capabilities.” It seems unlikely to me the company would advertise such functionality if it was not relatively close to offering this feature to its customers.

Second, the report suggests that the need for utilities to develop the software to control the V2G process in real time is a barrier to rapid deployment. Under the direction of Dr. Willett Kempton at the University of Delaware, the MAGICC demonstration has developed the communication and control solutions to allow direct dispatch of an electric vehicle by the regional transmission organization, PJM. Furthermore, another one of the Electrification Coalition members GridPoint offers a smart charging software solution for plug-in cars with V2G capabilities. I had a firsthand opportunity to participate in the demonstration of this software solution during a WebEx presentation last summer from a GridPoint representative. Thus the development of software solutions to control V2G resources should not represent a significant barrier to the technology's near-term deployment.

Finally, the Electrification Roadmap report states that much more information is needed to understand the impact on battery pack life from using GEVs as V2G resources. This is a legitimate concern that does require additional research. A paper published recently by researchers at Carnegie Mellon University titled Lithium-Ion Battery Cell Degradation Resulting from Realistic Vehicle and Vehicle-to-Grid Utilization concluded, “Statistical analyses indicate that rapid vehicle motive cycling degraded the cells more than slower, V2G galvanostatic cycling.” Furthermore, my research finds that the highest value uses of V2G resources are for grid regulation and spinning reserves. Grid regulation, the instantaneous matching of supply and demand to maintain grid frequency at 60 hertz, requires shallow cycles of charging and discharging of the battery depending on the mismatch between supply and demand at any moment. This type of cycling is much different than the charge depleting cycles from driving and thus should results in limited degradation. With regard to spinning reserves, grid resources are paid to be on stand by 24/7 in case of a contingency. Experience shows that these resources are rarely deployed and when they are dispatched in an emergency they are typically restored very quickly as non spinning reserves are brought online. V2G resources providing this service will receive significant revenue without ever needing to cycle energy through the battery pack. I encourage the Coalition to consider working with the Federal Energy Regulatory Commission and the regional transmission organizations to develop rules for the wholesale markets for ancillary services that allow GEVs to participate in these markets in a way that benefits the grid while minimizing the potential impacts on the vehicles.

I commend the Electrification Coalition for its exciting vision to initiate a rapid transition from a petroleum-base transportation system to one that is increasingly reliant on electricity. The report acknowledges that the initial high cost of battery technology creates a significant barrier to the realization of the 2040 goal. I am convinced that V2G deployment is a key enabler of the electric drive revolution. Research shows that a single V2G enabled car can generate well over tens thousand dollars in gross revenue over the life of the vehicle. While mass deployment of V2G systems will not be simple, smart grid technologies could serve to unlock the value of GEVs as grid resources to help mitigate the higher cost of these vehicles and accelerate their adoption.

Steven Letendre is a professor and energy consultant living in Vermont. Along with Dr. Willett Kempton, he published an article with the first full analysis on the V2G opportunity in 1997 titled “Electric Vehicles as a New Source of Power for Electric Utilities” appearing in the journal Transportation Research. Steven has served as a consultant to a variety of organization including the California Air Resources Board, National Renewable Energy Laboratory, Solar Electric Power Association, and the University of Vermont Transportation Research Center. He has published over 40 technical papers on a variety of energy topics, which have appeared in some of the leading energy publications including, The Electricity Journal, Energy Policy, and, Public Utilities Fortnightly. Steven can be reached by e-mail at letendres@greenmtn.edu.

Times Article Viewed: 9897
Published: 20-Nov-2009


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