Small Hydro Reference Model Project (Final Project Report)

Abstract

Small hydropower has long been developed in the United States, but still thousands of small hydro sites remain untapped. Most of them are technically and environmentally feasible but may not be cost-effective to develop at the current level of technology and carbon and fuel markets. This report aims to identify the cost drivers for small hydro generation through cost analyses, and to improve understanding of the pathways for cost reduction and the strategies for accelerating small hydro development in the United States. Reference to the empirical cost equations in literature, an initial capital cost (ICC) equation for nonpowered dam (NPD) and conduit projects has been preliminarily developed using limited project cost data collected from the Federal Energy Regulatory Commission (FERC) e-library and directly from industrial contacts. The regression analysis shows a correlation between the project ICC and plant capacity and head. The electro-mechanical equipment costs for Francis, axial flow, Kaplan, and propeller turbines are derived from the historical budget prices of a small hydro turbine manufacturer. These cost curves show the turbine-generator cost is also associated with the plant capacity and net head. In addition, the initial cost breakdowns are analyzed based on project cost data from literature and industry. It was found that the turbine-generator and the powerhouse are often the major cost components for low-head projects, whereas water conveyance is likely to be the key cost driver for high-head projects. The ICC variations for different site features, such as new greenfield sites vs. non-powered dams, are also discussed.