Application of Stirling Cycle Generators in Production Operations

Abstract

Abstract Clean, inexpensive, and reliable on-site electric power generation for remote wellsites is an emerging need. There is a growing demand for electric power sources in the range of ½ to 1.5 kW to run pumping units and pumps on liquid loaded gas wells. To understand one possible option, a pilot project consisting of three 0.8 kW Stirling Cycle electric generators was conducted in Wyoming. One generator was installed driving a conventional beam pump at the US Department of Energy's (DOE) Rocky Mountain Oilfield Testing Center (RMOTC). Two generators were installed for telemetry power service on well pads in the Wamsutter gas field. In addition to these two applications, small gas-fired generators could provide power for cathodic protection, chemical dosing systems, and other low rate pumping requirements. The pilot demonstrated that a Stirling Cycle generator can pump a small well and provide SCADA power even in cold weather conditions. A simple fuel control and conditioning system provided reliable operation when properly installed. Operations and maintenance observations from the 1 year pilot will be presented. Stirling Cycle engines are "external combustion engines" which offer some advantages over traditional "internal combustion engines": lower maintenance cost, low NOx emissions, and the recovery of heat for process uses. In fact, the current commercial equipment is best thought of as a ¾ kW cogeneration unit.