DI-114 – Development of an Advanced High Temperature High Pressure Downhole Power Supply

DEA Discussion Item Summary


Date Submitted: 7/12/2005

Title: Development of an Advanced High Temperature High Pressure Downhole Power Supply

Submitted by: Dexter Magnetic Technologies 1050 Morse Ave. Elk Grove Village, IL 60007 (847) 956-1140

Principal Investigator(s): Tim Price (Dexter Magnetic Technologies) tprice@dextermag.com John Cohen (Noble Downhole Technology) jcohen@noblecorp.com

Business Impact: The Advanced High Temperature Turbine Generator (HTTG) will have a significant impact on the cost of recovering gas from deep, hot wells. Current state-of-the-art Lithium-ion batteries (LIB’s) are not suitable for hotter environments. The most practical, if not only solution to power intelligent downhole tools in HTHP environments is a HTHP Turbine Generator. In addition, even if batteries were developed for elevated temperatures, they will still be very expensive and not reusable. The proposed HTTG will provide reduced dollar-per-amp-hour costs, an important benefit for reducing drilling costs and making deep, hot reservoirs commercially viable. Much effort and funding is being spent throughout the industry developing HTHP electronics and HTHP BHA’s. Without a suitable HTHP power supply, it will be impossible to use other intelligent drilling tools and technologies currently being developed for HPHT wells. This would negatively impact the economic development of future deep gas reservoirs in the USA.

Technical Objectives: The objective of this project is to develop a downhole high-temperature turbine generator (HTTG) capable of operating at high pressures (>20,000 psi) and high temperatures (≥250°C), to power equipment such as rotary steerable tools, MWD tools, LWD tools, and other components both currently commercial and those under development. Developing the HTTG presents two challenging and mutually exclusive tasks; consequently, the development phase (Phase II) is proposed as two parts—Phases IIA and IIB—with significant schedule overlap to increase the efficiency of the development effort. In Phase IIA, an electrical generator will be constructed to operate reliably in the deep downhole environment. The generator turbine blades will convert a small amount of the hydraulic energy in the mud stream to rotary energy, which is then converted to electrical power. In Phase IIB, electronics will be developed to rectify and regulate the power produced by the generator. Special electronics and mechanical components such as pressure housings and connectors will be developed to provide clean, regulated electrical power to third-party users. The rectifier/regulator will be designed to operate in the same high-pressure high-temperature environments as the generator. In Phase III, these developments will be combined as a complete HTTG tool. Field demonstrations will then be conducted and the system commercialized.

Methodology: This project to develop a HTTG for harsh environments will build on the success of DMT’s existing turbine generator (UnderCurrent™) that is currently built for conventional temperatures and pressures. This tool uses customized turbine blades and a magnetic coupling to turn a generator that is housed in a pressure barrel. Development of the HTTG will start with development of specifications for each of the two major components to meet the project requirements. Then the existing components will be characterized on a part-by-part basis to determine which areas must be upgraded to meet the new HPHT specifications. This process will be very detailed and will identify both parts and failure modes. An efficient design and testing program will be undertaken to upgrade parts and subsystems until a working prototype HTTG is developed and tested. Finally, the HTTG will undergo field demonstration for various applications and be commercialized.

Deliverables: Deliverables will be a working and field tested Turbine Generator system to provide regulated power for HTHP application. The units will be manufactured and commercially marketed by Dexter Magnetic Technologies. Participants in the project will be offered first deliveries and preferential pricing. After initial deliveries are offered to project participants, the product will be made available industry wide.

Comments: Note: Lab flow loop testing at 20,000 psi and 250 deg. C is not currently available. Therefore, prototype units will be outfitted with a load cell and data acquisition capability so they can be run in actual HTHP drilling environments, as a non-intrusive component.