IEEE Electrification - June 2019 - 41

is reluctant to invest in developing and deploying V2G
technology. As part of CEC-funded project 14-086, Distribution System Aware Vehicle to Grid Services for Improved
Grid Stability and Reliability, Energy and Environmental
Economics, Inc. (E3) was tasked with quantifying the
potential benefits of V2G technology for California's ratepayers across a variety of use cases. In this article, we
share results and key insights from E3's study. We believe
that these results provide regulators and industry with the
critical information necessary to help identify the best
opportunities for V2G technology in California.

Modeling the Electric Grid Benefits of V2G
Optimized Dispatch Using the CEC
Solar + Storage Tool
To estimate the electric grid benefits of V2G, we conducted a case study covering several scenarios and use cases
between the present and the year 2030. The case study
was performed using the CEC Solar + Storage Tool developed by E3. New EV-specific modeling and dispatch optimization features were added to the tool, including the
unique constraints that transportation creates for EVs
used as DERs. The model optimizes a joint-dispatch
schedule for a group of EVs that plug in at a common

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places where EVs have become popular. V1G programs in
California include San Diego Gas and Electric's Power Your
Drive, EV-specific retail tariffs from Southern California
Edison, and the Charge Forward smart charging pilot program from Pacific Gas and Electric in collaboration with
automaker BMW.
The capability to inject power from an EV's battery
into the electric grid is known as vehicle-to-grid (V2G).
Adding V2G capability to EVs would enable them to deliver much greater benefits to the electric grid than V1G.
There are, however, significant barriers to the widespread
deployment of V2G, including the development of standards for information exchange, regulatory frameworks,
and business models. These barriers are similar to those
facing other distributed energy resources (DERs) but are
even more complex because vehicles are mobile and
require the flexibility to connect to a variety of EV service
equipment (EVSE) and charge or discharge at many different locations.
Another key barrier to further development and
deployment of V2G identified at the California Energy
Commission's (CEC's) recent VGI Roadmap Update Workshop is a lack of knowledge about the value that V2G can
provide and what the most promising V2G use cases are
for capturing that value. Without this knowledge, industry

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Work Discharge
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Figure 1. (a) A V1G and (b) a V2G dispatch during solar overgeneration for a single EV at home on a weekend day.

IEEE Elec trific ation Magazine / J UNE 2 0 1 9

IEEE Electrification - June 2019

Table of Contents for the Digital Edition of IEEE Electrification - June 2019