Unconventional oil and gas development revolutionized the energy sector in North America and has been transforming the world's energy markets. Notwithstanding the enormous potential, unconventional resource development presents unique challenges to production and long-term hydrocarbon recoveries. As market dynamics are shifting, technologies are advancing, opening up new opportunities in areas once considered out of reach. This paper describes a new technology, a subsurface compressor system, which simultaneously removes liquids, increases gas production, and improves recoverable reserves in gas wells. The subsurface compressor can reverse the vicious cycle of liquid loading, which decreases gas production from a gas well and leads to premature abandonment, by creating a virtuous cycle of increased gas and condensate production. The complete process from well analysis, performance projection, deployment, commissioning to operation are discussed. A recently completed the world's very first field trial in an unconventional shale gas well supports the mechanism of subsurface gas compression and its impacts and benefits on unconventional gas production.

A new technology, Magnetic Drive System (MDS), to increase reliability and retrievability of electrical submersible pumps (ESPs) is described. With the improved reliability and retrievability, the production uptime of oil wells with artificial lift and the total cost of ownership of ESPs are improved significantly. An industry survey and literature review were conducted to identify the aspects of the ESP and the failure-prone ESP subsystems to improve upon. Based on the findings, the MDS technology is developed to improve ESP reliability by isolating the failure modes and to improve ESP retrievability by enabling fast deployments and retrievals from wells. Mean Time Between Failure (MTBF) models based on field observed failure mechanisms are applied to identify the impacts of isolating various failure modes on ESP reliability. The total cost of ownership (TCO) is calculated to illustrate the advantages of the MDS system to increase production gains and reduce costs. Analysis on ESP reliability shows that the electrical system is the primary ESP failure mode, covering more than 50% of the failures. Models based on field data from the literature review shows that MTBF can be more than tripled if these failures are eliminated. The MDS topology places all the electrical components, including motor stators, cables and penetrators, of an ESP in the isolated annulus space between the permanent completion and tubing, leaving only the mechanical components, including the permanent magnet motor rotors and pump stages, inside the production tubing. In this case, the electrical components are well protected from the hostile produced fluids, so that the failures modes of the electrical system are eliminated. Since the retrievable string has no electrical components, such as thousands of feet of power cable, the deployments and retrievals of the retrievable string can be easily done by slickline. The larger motor stator and higher power density enabled by enhanced heat dissipation of the MDS topology dramatically increase the motor horsepower and shorten the motor length, thus increasing the production gains of the ESP. Reliability and retrievability are further improved due to the elimination of motor protectors and replaced by the "built-in" magnetic coupling between the MDS motor stator and rotor. With the improved reliability, retrievability, and motor performance simultaneously, MDS reduces the total cost of ownership by more than 70% in some cases compared with the conventional tubing-hung ESP, enables live well deployment and retrieval, reduces production downtime and intervention complexity, and protects reservoir productivity.

This development is the result of a DeepStar program to build and test a new radial passive magnetic bearing system (PMB) for downhole tools. While slated for the Magnetic Drive System (MDS) ESP, an advanced high-speed ESP that uses magnetic fields to increase performance, reliability and retrievability, this technology is applicable to conventional ESPs. The PMB supports the motor rotor across large clearances with no physical contact via magnetic fields in the ESP. An MDS ESP preliminary design was developed, from which the size and integration requirements of the PMB were defined. These requirements guided the analysis, design and testing of the full-scale components. Empirical analysis tools were used for initial iterations in size and performance of the PMB, followed by detailed magnetic finite element analysis (FEA) using commercial validated tools for the final performance prediction. With analytical validation of performance, detail designs were developed and hardware fabricated. Hardware testing was done to validate performance predictions and alignment with system requirements. The feasibility, preliminary design and analysis of the PMB were conducted in Phase 1 of the DeepStar Program and has continued with the full-scale design, build and test results of Phase 2. PMB performance results include load capability and deflection during static load events, all in relation to validating performance for use in the MDS system. This test data is used to validate the analysis approach used as well as to finalize the integration size of the PMB to meet the performance requirements of the MDS system. With the PMB large (>14mm) clearance between rotor and stator magnets, testing also includes variations in axial and radial position of the rotor in relation to the stator to account for installation variations in the MDS as well as use of sealing materials on both the rotor and stator. Integration is planned for use of the PMB in the MDS, so integration testing is planned to validate performance for each of these areas. This technology offers a radial bearing that can greatly enhance ESP performance and reliability. The PMB is a contact-less bearing system that does not require lubrication, can operate with large clearances to allow free fluid flow, is easily fully sealed from the environment, has virtually no bearing rotating losses, and has no operating life limits.