High Temperature Instrumentation Development and Commercialization for Geothermal Applications

Abstract

Instrumentation for making geothermal borehole measurements limited by the temperature capabilities of existing logging equipment developed for the oil and gas industry. The Geothermal Logging Instrumentation Development Program is being conducted by Sandia Laboratories for the Division of Geothermal Energy (DGE/DOE). This program emphasized the development and field test performance verification of severe environment components such as 275°C electronics, high temperature high resolution pressure transducers, elastomeric and metal tool seal, cablehead, and cables. Since the report to the GRC last year, a number of these essential developments have come to fruition: a set of prototype geothermal logging tools (temperature, pressure, and flow), cable and cablehead were successfully field tested to temperatures up to 275°C in a geothermal well during November 1978; an experimental high resolution quartz pressure transducer was successfully test up to 275°C and 1000 psi; a gallium phosphide diode was developed and found to operate successfully up to 400°C; and the mechanical clocks in the Amerada gauge were upgraded in temperature and reliability.