Two intersecting events of the last two decades have transformed the electricity industry: (1) market restructure designed to introduce wholesale market competition; and (2) renewable energy development fostered by government policies, including renewable portfolio standards (RPS). There is, however, little research to answer the question: what is the avoided cost of demand response (DR) in a restructured market with RPS? This paper offers an answer to this question, which is critical for determining the cost-effectiveness of DR and its program design and implementation. We illustrate the answer's usefulness with five real-world examples of permanent load shifting (PLS) in California. These examples show that a PLS system's cost-effectiveness depends on its site-specific characteristics, including location, installation cost and performance, thus affirming the use of a targeted approach to DR design and implementation. (C) 2011 Elsevier Ltd. All rights reserved.