This article presents an economic analysis of a Cu-Cl pilot plant with an associated parametric study. The analysis takes into account the different types of cost components such as the energy costs, operation, maintenance, fixed charges on capital investment, etc. The cost items with their percentage ranges and factors that affect accuracy and scaling are examined. Through this scaling method, the total capital investment and total cost of a Cu-Cl pilot plant are estimated by scaling against the corresponding costs of an S-I plant as presented by Brown et al. Using a six-tenths-factor rule (scaling method) with a capacity factor of 0.6, the fixed-capital investment and product cost of a Cu-Cl pilot plant are roughly estimated at about US$27.5 M and US$4.6 M for a plant capacity of 5 tons of hydrogen per day, which could be higher due to yet unforeseen factors and costs, not currently available with existing information about the Cu-Cl cycle. The fixed-capital investment and total product cost correspond to the operating and maintenance costs of the plant, respectively. The sensitivity studies show that the costs vary significantly with the size of pilot plant capacity, percentages of cost components and the capacity factor. The parametric studies with variable plant capacities, approximations and capacity factors are performed and results are illustrated in this article. Numerous assumptions and approximations have been used in this paper, in absence of actual equipment cost data for the Cu-Cl cycle. Therefore, the results of this paper cannot be generalized for other specific cases and scenarios. (C) 2008 International Association for Hydrogen Energy. Published by Elsevier Ltd. All rights reserved.