The integration of Energy Storage System (ESS) in our existing power system has become a key concept of study and research in recent years. Due in part to their versatility, they can support multiple applications at all levels of a power system. These devices are not only focused on power management but also play an important role in enhancing the quality and resiliency of a power system. The state of California has been an early proponent of the increased deployment of energy storage. The California Independent System Operator (CAISO) has helped facilitate this goal through the creation of three different participation models. The Non-Generator Resource Model (NGR), Proxy Demand Resource (PDR), and the Distributed Energy Resource (DER) model allow energy storage resources located in the CAISO footprint to bid capacity into a variety of wholesale energy and ancillary service markets. The value associated with each mechanism can be modeled using historical price data available to the public through CAISOs Open Access Same-Time Information System. The NGR model can be divided into Non-REM (Non Regulation Energy Management) and REM (Regulation Energy Management) subtypes. The Non-REM resource model provides opportunities for arbitrage, regulation, and reserve market participation while the REM resource model only deals with the regulation market.In this study, optimization models that include the cost of system degradation due to dispatch are proposed for each NGR subtype that can be used to estimate the maximum profit of an ESS participating at a given market node in the CAISO system. As ESS are often uncompetitively priced in relation to traditional technologies, this study is further extended to consider the profit opportunities available to second life battery systems. To this end, the models are also implemented for the second-life battery systems and a comparison is made between existing, brand-new, and second-life battery systems to understand their performance individually.
