Multi-queue model is used to cooperate different deadlines and packaging technique for charging rate limit. It is shown by simulation results, based on real electricity price and renewable energy data, that the charging cost can be reduced by 78% and 33% on average compared to two greedy approaches: “charge-upon-arrival” and “purchase-at-deadline” respectivley, and the mean delay time can be reduced by 65% as compared to the “purchase-at-deadline” approach. Moreover, since the proposed charging scheduling schemes based on Lyapunov optimization does not require the statistics of underlying processes, such as future renewable energy generation, real-time electricity price and charging demand, it can be applied when the aggregator has no such prior
knowledge, while other optimization methods which require those pieces of information, such as dynamic programming or robust optimization, will be unable to do the calculation.