Reliability-based Capacity Expansion Planning for Decarbonization with the Aid of Energy Storage

Jurisdictions around the world are enacting and enforcing an increasing number of policies to fight climate change, leading to higher penetration of renewable energy resources (RERs) and energy storage systems (ESSs) in the power grid. One of the biggest challenges associated with RER integration is determining the optimal portfolio of resources that can be integrated into the system at the lowest cost while also ensuring a reliable system. This paper proposes a long term expansion planning framework for calculating the optimal portfolio of resources that minimizes the investment and operational costs as well as ensures a pre-determined level of system reliability using ESS, all the while adhering to the decarbonization policies applicable to the system. A capacity expansion planning (CEP) framework and a resource adequacy framework (RA) are developed which interact amongst themselves to determine the optimal resource mix. The linear programming based CEP model focuses on minimizing the total investment costs over the planning horizon while satisfying the decarbonization goals of the local jurisdiction. The Monte Carlo simulation based stochastic RA model evaluates the reliability of the portfolio obtained from the CEP model and determines ESS requirements based on achieving a pre-determined reliability target. The efficacy of the proposed approach is demonstrated using the latest edition of the IEEE Reliability Test System.