It is particularly critical how to deal with imbalances resulting from prediction errors in outputs of renewable power sources. In this report, we propose a novel procedure to use batteries and electric vehicles to deal with the imbalances. We develop a mathematical model, taking account of profitability of the companies, to clarify optimal introduction quantities and utilization procedures of batteries and electric vehicles. Computed results implied that the imbalances could be reduced by approximately 70% without decreasing profitability of the regional power companies.