Electric energy cost reduction by shifting energy purchases from on-peak times

This paper reports simulated results that detail the effects of the parameters that control the charge/discharge operation of a Battery Energy Storage System (BESS) located on a distribution feeder. The following BESS parameters were evaluated: energy capacity, maximum discharge current, and “round-trip” efficiency. Also, the following system parameters were studied: marginal cost (MC) of electric energy, and the 24 hour load profile of the feeder. The BESS performance was quantified as a function of the differential cost of energy (DCE) representing the difference between the cost of energy purchased to charge the BESS and the cost of energy delivered, (sold). The obtained results prove that the use of BESS can be beneficial, yielding significant savings, if the battery size is sufficiently large and the battery efficiency is high enough.