Electric Submersible Generators – Using ESPs in an Unfamiliar Way

Abstract

Abstract Electrical Submersible Pumps (ESP) have been used to produce fluids for almost a century in many different industries. Since the 1800s, people have been using hydroelectric dams to produce power, demonstrating the viability of harnessing the potential energy from elevated water sources. However, there is a tremendous opportunity to partially recover that same potential during the yearly reinjection of billions of cubic meters of water in the oil, gas, and geothermal industries by combining the principles from both. The electrical submersible generator (ESG) is a modern interpretation of an old idea. The ESG can generate electricity to meet surface power needs or feed directly into the grid to create a revenue stream under the proper injection conditions. In typical configurations, a standard centrifugal pump is used in combination with an induction motor. Rather than operating the motor in a conventional manner to convert electrical energy to mechanical work, the motor is operated in such a way for the mechanical work of the pump to be converted into electrical energy. Other configurations are optional such as using more conventional turbine pump designs and permanent magnet motors. After the successful completion of a few installations, several changes have been made to optimize the machinery and enhance the equipment operation. Through these efforts, significant knowledge has been gained about how these machines work. For a successful completion, factors including third-party controls, run-away speeds, fluid / reservoir properties, and starting techniques must all be considered. This paper explores the ESG’s design considerations, theoretical underpinnings, and potential future applications. This will involve a review of field operations, installation procedures, and lessons learned. The conclusions of CFD analysis and installations in the actual world will be presented to support the assumptions.