Abstract
In Japan electricity market will open on 1st April 2004. Electric utility, Power Producer and Supplier (:PPS) and Load Service Entity (:LSE) will join to the electricity market. LSEs purchase electricity based on Market Clearing Price (:MCP) from electricity market. LSEs supply electricity to the customers contracted with the LSEs on a certain electricity price, and one to the customers introduced Energy Storage System (:ES) on a time of use pricing. It is difficult for LSEs to estimate whether they have incentive to promote customers to introduce ES or not. In this paper, it is evaluated the reduction of LSEs' purchasing cost from electricity market and other LSEs' purchasing cost by introducing customers ES. It is clarified that which kind of customers has the effect of decreasing LSEs' purchasing cost and how much MCP of whole power system the demand-side energy storage systems change. Through numerical examples, this paper evaluates the possibility to give the cost merit to both customers with energy storage systems and LSE by using a real data of yearly MCP.