A planning model for electric vehicle aggregators providing ancillary services

This paper introduces a planning model that can be used by an investor who would like to provide ancillary services (AS) to electricity markets. The proposed model helps the investor evaluate two potential options: aggregating distributed batteries in electric vehicles (EVs) or using a dedicated energy storage system (ESS). For EV aggregations in AS markets, the targeted EV fleet size, which is a function of energy tariff charged by the EV aggregator, is a key planning consideration. In the case of ESS, the physical size is the main planning consideration. Using the proposed model, the two options for maximizing the investor's long-term payoffs are analyzed and compared by assuming the same initial investment cost for both options. Accordingly, the investor's daily bidding strategy in AS markets is optimized for each case. The net present worth is used as the basis for comparing the two investment options, and sensitivity analyses are carried out to study the impact of planning and operation variables on the feasibility of the two options. Simulation results consider both options and discuss the results for providing AS to electricity markets.