Clean vehicles as an enabler for a clean electricity grid

TLDR

California has issued ambitious targets to decarbonize transportation through electric vehicle deployment and to decarbonize the electricity grid via renewable generation and energy storage expansion, creating a synergistic opportunity for clean transportation to enable a clean grid. The study aims to quantify the potential of EVs to mitigate renewable intermittency by forecasting hourly system‑wide balancing problems up to 2025 as renewables and load grow. The authors model how EVs can modulate charging or discharging to provide balancing benefits without compromising driver mobility. Results show that one‑way charging control of EVs can achieve most of the storage mandate’s benefit at a fraction of the cost, and two‑way control multiplies these benefits, supporting renewable integration while avoiding large stationary storage investments.

Abstract

California has issued ambitious targets to decarbonize transportation through the deployment of electric vehicles (EVs), and to decarbonize the electricity grid through the expansion of both renewable generation and energy storage. These parallel efforts can provide an untapped synergistic opportunity for clean transportation to be an enabler for a clean electricity grid. To quantify this potential, we forecast the hourly system-wide balancing problems arising out to 2025 as more renewables are deployed and load continues to grow. We then quantify the system-wide balancing benefits from EVs modulating the charging or discharging of their batteries to mitigate renewable intermittency, without compromising the mobility needs of drivers. Our results show that with its EV deployment target and with only one-way charging control of EVs, California can achieve much of the same benefit of its Storage Mandate for mitigating renewable intermittency, but at a small fraction of the cost. Moreover, EVs provide many times these benefits if two-way charging control becomes widely available. Thus, EVs support the state's renewable integration targets while avoiding much of the tremendous capital investment of stationary storage that can instead be applied towards further deployment of clean vehicles.