Using Downhole Electric Heaters to Complement or Replace Cyclic Steam Stimulation Operations

Abstract

The combination of downhole electric heaters with Cyclic Steam Stimulation (CSS) operations has been successfully piloted in a California heavy oil field. This paper focuses on a field case study of the installation of an electric heater in a horizontal CSS producer with the primary objective of extending the duration of the production phase of the well’s average steam cycle. History matched thermal reservoir simulations based on the results of this field trial predict that operating an electric heater in a comparable well from the beginning of its life could extend the duration of the average CSS cycle by at least 90% while maintaining equivalent cumulative oil production over a 5-year period. The history matched model was adapted for steam cycles of various durations ranging from 3 to 8 months, and the benefits of extending these cycles’ durations using the hybrid downhole heater application are analyzed. Further modeling work determined that doubling the length of the productive interval of the field’s average horizontal CSS well while electrically heating could completely eliminate the need for steam injection and increase oil production on a per-well basis by more than 10%. Reductions in CO2 emissions through the elimination of steam are estimated to be greater than 80%, and reductions in water consumption can reach as high as 100%. Whether electric heaters are used to complement CSS operations by extending steam cycle duration, or to replace CSS operations with longer horizontal wells, significant economic and environmental benefits can be realized by implementing the technology.