We present an evaluation of a new version of the web-based clean power estimator (CPE) capable of evaluating the effectiveness and value of solar load control (SLC) for commercial applications in the US. Three experimental building case studies are used as a validation benchmark. The selected buildings include a large office building near New York City, a department store in Long Island, and another department store in Hawaii. The results of the CPE calculations are compared against results obtained using actual building load and colocated hourly actual solar radiation data. (C) 2003 Elsevier Ltd. All rights reserved.