Dive Brief:

• Electric vehicles (EVs) could play a major role in balancing the grid by soaking up excess solar generation during the middle of the day, according to analysis from researchers at Lawrence Berkeley National Laboratory.
• Based on an analysis of California's stationary storage mandate and its decarbonization and EV adoption goals, the study concludes much of the storage mandate may be unnecessary if electric vehicle charging can be coordinated.
• Despite optimistic outlooks for adoption, data from the U.S. Energy Information Administration concludes EVs "have been slow to gain market share in the United States." But a closer look at the data reveals sales trends that may portend growing interest.

Dive Insight:

Utilities increasingly see electric vehicles as a grid resource they want to encourage. But EIA's data reminds us that, so far, little progress has been made in widespread adoption.

The share of "electrified vehicles," including hybrid electric vehicles, plug-in hybrid electrics and battery electric vehicles, as a portion of total light-duty vehicle sales has remained relatively constant over the last five years — typically somewhere between 2.5% and 4%, according to the agency.

But changes are occurring. Hybrid electrics (think: Prius) made up most of those sales from 2012 to 2017, but their share has been declining as interest has grown in battery electric vehicles. Since 2012, battery-only electric vehicles have grown the most as a portion of light-duty sales, but still accounted for less than 1% each year. So while they may be viable grid resources some day, there is still work to be done.

Last year the Edison Electric Institute and Institute for Electric Innovation forecast up to 7 million EVs on U.S. roads by the end of 2025

And LBNL research shows there may be significant grid benefits and financial incentives.

"California can achieve much of the same benefit of its Storage Mandate for mitigating renewable intermittency, but at a small fraction of the cost," researchers wrote in their paper, "Clean vehicles as an enabler for a clean electricity grid," published by Environmental Research Letters.

EVs can provide that benefit with only one-way control, but "provide many times these benefits if two-way charging control becomes widely available," they added.

According to paper co-author Samveg Saxena, the capital investment savings from using EVs for such grid balancing instead of stationary storage could amount to several billion dollars. 

"Those savings could be redirected to further accelerate the deployment of clean vehicles and vehicle-grid integration, and could even be used to pay EV owners when their vehicles are grid-connected with controlled charging," Saxena said in a statement.

In 2013, California regulators required the state's three large investor-owned utilities to procure 1,325 MW of storage by 2020, with another 500 MW subsequently added to the IOU requirements.