There is a growing interest in utilizing energy storage for behind-the-meter customers. Energy storage systems have many functions for behind-the-meter use such as energy time shifting, peak demand shaving, and backup power. However, demand side management of energy consuming systems can also provide similar energy shifting functionality often with a significantly lower upfront cost. Though energy storage systems and demand side management can both be applied, each option has strengths and weaknesses that can make the optimal selection of measures difficult in many cases.
In this study, the tradeoff between energy storage and demand side management is investigated at the Hawaii Ocean Science and Technology (HOST) park of the Natural Energy Laboratory of Hawaii Authority (NELHA). The major energy consumption at the HOST park is for pumping the seawater that serves many functions at the park, including supplying temperature-controlled water for various agriculture applications and even building air conditioning measure. NELHA’s facilities are broken into two major load centers that are connected by the piping network, though they are electrically isolated and subject to different electricity price tariffs. This scenario is modeled to optimize the dispatch of the pump stations and potential battery systems to minimize the cost of electricity for both load centers. This scenario is a good example of the interplay between demand side management and energy-storage-based cost reduction measures.