The Estimated Costs as a Function of Depth of Geothermal Development Wells Drilled in Nevada

Expected well costs can be a major factor in whether companies obtain financing due to expense and moderate success rates of drilling. Well permitting records are reported by state agencies, and well production from individual wells within producing areas are reported monthly (in NV) so that one can determine, in retrospect, which of the permitted wells actually led to geothermal production and power generation. A companion paper (Shevenell, 2012, this volume) compiles and evaluates geothermal well records submitted to the Nevada Division of Minerals, and estimates the success rates of geothermal wells drilled in Nevada since the early stages of exploration in the 1970s and 1980s, through construction of the power plants currently in existence in northern Nevada. This paper uses that information to estimate the minimum expected costs associated with drilled wells and production per MW, assuming well depths are a dominant factor in determining costs. Because depths are not the only factor determining power plant costs, costs noted here are likely minima. Introduction This paper uses well records compiled by the Nevada Division of Minerals to estimate the range of drilling costs for Nevada geothermal wells. The well depth data are available from the early stages of exploration in the 1970s and 1980s, through construction of the power plants and are used to calculate total and average well depths and associated minimum costs by producing area. It is common to hear comments related to the “success rate” of geothermal The Estimated Costs as a Function of Depth of Geothermal Development Wells Drilled in Nevada