Transmission planning with renewable generation and energy storage

摘要

An energy storage system (ESS) can provide regulation and reserve capacities for the power system, and hence alleviate the negative impacts of renewable energy such as wind power. Nonetheless, challenges remain as to how the operation of wind farms and ESSs can be coordinated efficiently, and how transmission system expansion planning will be impacted. This paper addresses these challenges by: (1) examining the correlation between the cost of ESS and its cycle life, exampled with a Natrium Sulfur (NaS) ESS; (2) investigating the integrated operation of a wind farm and an ESS taking into account both the cost of ESSs and their smoothing effect of wind power fluctuations; (3) developing a transmission system expansion planning model with particular reference to both the investment cost of the transmission system concerned and the operating costs of wind farms and ESSs; and (4) solving the developed planning formulation using an improved particle swarm optimization algorithm. The proposed planning method is illustrated through its applications to two sample systems.