Significant electrification of the transportation sector is necessary for the State to achieve several important greenhouse gas (GHG) reduction and renewable energy targets. The State’s electricity generation and transmission capabilities must increase in order to meet the demand generated by increasing levels of fleet electrification. The increased demand, combined with the Renewables Portfolio Standard (RPS) targets will require significantly increased energy storage capabilities that can accommodate demand while integrating renewable power sources into the grid. This project evaluated the mid to long-term energy storage needs of the electric grid for select fleet electrification scenarios. The analysis was conducted using Resolve, a power systems planning model, for RPS targets of 60% and 80% by 2030 and 2042 respectively. The results show that Electrical Energy Storage (EES) capacity requirements depend on a number of parameters, including Demand Response (DR), Electric Vehicle (EV) charging flexibility, and total EV population. The EES requirements for the 60% RPS scenarios range from 3.9 to 4.3 GW while for the 80% RPS scenarios, the range is from 18.5 to 20.4 GW.