The Permian basin is the largest oil field in the U.S., but it is also one of the world’s biggest methane emitters. As producers come under pressure to cut emissions to tackle global warming, electric actuation can slash emissions, while making processes more efficient.
CHRIS HARDY, Rotork
The first oil well was drilled in the Permian basin of the U.S. in 1920, but by the beginning of the 21st century, the area, which had once been the source of vast oil supplies, seemed to be fading. When new technology was deployed, however, it revealed there was more petroleum still trapped beneath the ground than anyone could have imagined.
Since then, the 86,000-mi2 basin, which spans parts of West Texas and New Mexico, has been named the largest oil reserve on the planet and is now one of the most prolific oil and gas fields in the world. It accounts for nearly 40% of oil output and 15% of natural gas production in the U.S.,1 and its potential is unparalleled.
The Permian basin is one of the oldest and most well-known hydrocarbon-producing areas in the world. Since 1920, more than 30 Bbbl of crude oil have been recovered, and experts now predict there are at least 20 Bbbl remaining. Extracting the remaining oil and gas in the age of global warming will require new technology and new thinking.
The Permian is expected to average 6.3 MMbopd in 2024, an increase of nearly 8% from 2023.2 But even as producers extract more valuable resources, they are coming under increasing pressure to cut emissions. The International Energy Agency (IEA) warns that the oil and gas industry needs to reduce its emissions 60% by 2030, to align itself with a global rise in temperatures of just 1.5°C.3
Fortunately, the IEA believes the industry is well-placed to scale up some crucial technologies for the energy transition.4 Electric actuation is one such technology that has the potential to help companies in the Permian rapidly decarbonize. It uses less power than more traditional pneumatic actuation, while controlling flows of liquids and gases much more precisely and helping to slash emissions of methane, one of the most potent greenhouse gases.
TACKLING METHANE EMISSIONS
Methane is responsible for 30% of the rise in global temperatures, since the Industrial Revolution, and for at least 25%5 of current global warming. These emissions are thought to represent $1 billion5 in lost commercial value for U.S. energy producers, alone. If the gas could be controlled better, it could be sold as natural gas, converted to fuels, used for chemical production, or stored underground.
In March this year, Stanford University published the results of research, which found that oil and gas operations across the U.S. were emitting more than 6 million tons of methane per year. These emissions come from both intentional vents and unintentional leaks and are roughly three times the level estimated by the U.S. government.
The data came from around a million aerial measurements of U.S. wells, pipelines, storage and transmission facilities. While emissions in three key regions were well above expected values, the New Mexico portion of the Permian basin was found to be the highest emitter, with nearly 10% of the methane produced going straight into the atmosphere in 2019.5
The study followed the Permian Methane Analysis Project, which was carried out by the environmental advocacy group, Environmental Defense Fund (EDF), between 2019 and 2021. More than 100 flights collected aerial methane data during this time and concluded that Permian methane emissions were between two and three times higher than estimates from the U.S. Environmental Protection Agency.
According to the group’s research, 1.4 million metric tonnes6 of the gas are released each year from the basin—enough to meet the annual gas needs of nearly two million homes. But methane emissions can be reduced by more than 75%7 with simple solutions, such as leak detection, repair programs and upgrading leaky equipment to include electric actuators.
BRINGING IN NEW TECHNOLOGIES
The electrification, digitization and automation of upstream processes offer the chance to significantly improve the efficiency of oil and gas production while helping to meet climate goals. They are likely to play a key role in the Permian, which is set to provide the oil and gas needed to power the U.S. economy for years to come, despite the shift toward renewables.
Production control valves in upstream processes have traditionally been operated by pneumatic diaphragm actuators that use the wellstream gas as their motive power, releasing methane every time the valve is stroked. To reduce these emissions, some operators have now replaced wellstream gas with air compressors, but these require a good deal of power and do little to limit the operator’s carbon footprint.
Low-powered electric actuators use little energy. Many provide self-contained, one-piece actuation solutions, which reduce the risk of failure, compared to the typical pneumatic solution involving multiple components. They provide the necessary torque and thrust, while operating at the required speeds for choke and process control valves in upstream applications.
Electric actuators are suitable for applications, such as gas metering, production trees, processing, saltwater disposal and gas lift systems, Fig. 1. Many come with fail-to-position options that automatically return valves to a predetermined position, in case of power loss or emergencies. This enhances safety and prevents potential damage to equipment.
Using electric actuators instead of pneumatic solutions not only helps to reduce emissions but results in cost savings and increased operational efficiency. Rotork electric actuators, such as the intelligent IQ3 Pro, CMA and CVA process control actuators, also feature user-friendly interfaces and software tools that simplify the commissioning process. This makes them a perfect solution for valve applications in the oil and gas industry.
GATHERING VALUABLE DATA
Many electric actuators can also gather valuable data. Rotork has included data loggers in its IQ range since 2000, making them suitable for use in asset maintenance systems. These intelligent solutions are designed to provide reliable and repeatable performance in the dynamic and challenging environments of remote oil and gas well sites, like those found in the Permian. They monitor temperature, torque and voltage to ensure the unit's integrity and operating performance, resulting in a longer product lifespan.
The advanced technology uses data to optimize processes, facilitate efficiency and improve overall productivity. In East Texas, Rotork IQTF intelligent actuators support electrification by carrying out modulating duties on wellhead rotary non-rising choke valves. They control the flow and pressure of gas and condensate.
Intelligent flow control systems can monitor valves and identify any issues early, before they become serious problems. This, in turn, saves time and money on repairs and reduces downtime. They can automatically adjust valve conditions to reduce energy consumption and emissions. The actuators collect data on everything from valve operations to torque profiles, to help operators better understand their flow control systems and ensure that facilities operate effectively.
DEPLOYING ELECTRIC ACTUATORS
Rotork intelligent electric actuators have been deployed, for example, in upstream oil and gas production in both an East Texas section of the Haynesville/Bossier shale gas formation and a Jurassic period rock formation covering large parts of Southwest Arkansas, Northwest Louisiana and East Texas. These actuators are also being used by the same company at the Eagle Ford basin in South Texas. These operations, as well as the company’s oil and gas assets in the Permian-Delaware basin, contribute to it producing 190,000 boed in Texas and Louisiana.
Rotork’s lightweight, compact IQTF actuator provides fast and accurate valve control and can perform up to 1,800 starts per hour—an important factor, given the need for a tight well flow threshold to avoid overpressure in the main trunkline. If too much gas is extracted in a short period of time, the reservoir can implode or cause ground fractures, which water or gas can infiltrate, causing a loss in production.
IQTF actuators are available with rotary, linear or rising stem valve drive outputs. An internal lubrication system, sealed for life, ensures reliability for the actuators installed on wells at unmanned, remote sites. This system uses oil, which can perform in temperatures ranging from -50 to +70 °C (-58 to +158 °F)—ideal for the environment in East Texas, where temperatures very rarely drop below the lowest point.
ELECTRIC ACTUATORS HAVE IMPORTANT BENEFITS
The benefits of electric actuation for operators in regions like the Permian basin are evident across upstream applications.
Production trees. The production tree (also known as a Christmas tree) is an assembly of valves, spools and fittings that regulate the flow of oil or gas from a well. In the event of overpressure, a Surface Safety Valve (SSV) is a fail-safe/shutdown valve installed at the upper wellbore, for emergency shutdown to protect the production tunings. A production choke valve controls the flow of well fluids being produced and regulates the downstream pressure in the flowlines. Electric actuators like the Rotork IQT3F Pro are designed for advanced production choke valve actuation.
Production processing. Pneumatic diaphragm actuators have traditionally operated control valves in the upstream production process (Fig. 2), frequently venting methane. Rotork's electric control valve actuators are an advanced and energy-efficient alternative. They are suitable for dump valves and back-pressure control valves, commonly used in upstream production processing applications. These actuators not only help achieve net-zero emissions with a solar-powered 24 VDC supply option, but they also help reduce overall life cycle costs compared to the instrument air actuator alternative.
Gas metering and LACT skids. Natural gas production metering and Lease Automatic Custody Transfer (LACT) for oil production metering are two crucial aspects that connect upstream operations to midstream gathering infrastructure. Multiple flow control systems operate on a custody transfer metering skid, Fig. 3. The flow control on metering skids must be highly accurate and reliable and always provide safe valve operation. To automate large control valves with high-pressure ratings, a high-output actuator like the CML can deliver increased linear thrust and stroke length.
Gas lift system. When extracting oil from underground wells, a gas lift system is used to lift the fluids to the surface, Fig. 4. This system works by injecting high-pressure gas into the well to reduce the density of the fluids and lower the pressure at the bottom of the well, allowing the fluids to flow more easily. A control valve modulates the flow and pressure of the gas being injected into the well. The CMA electric actuator is suitable for this application. It is designed to operate continuously and precisely, making it ideal for continuous, modulating applications like gas lift systems.
Saltwater disposal systems. Produced water is the largest liquid produced in the oil and gas industry. It is transported to recycling tanks or saltwater disposal wells through an intricate gathering line network. The system is fitted with actuated valves requiring a high degree of controllability to prevent water hammering. Additionally, back-pressure control valves must operate with high-frequency modulation duty, to ensure optimal performance of water injection pumps. Rotork’s CMQ and IQT3M Pro actuators offer adjustable speed—including a slow mode for precise positioning—high accuracy, high-resolution micro-step movement and flexible torque/thrust protection.
Electrification, digitization and automation will be increasingly essential to upstream operators in the Permian, as a way to both increase efficiency and reduce emissions as regulations become stricter. They also offer a way to overcome the looming skills crisis in the industry. Electric actuators are the unsung heroes of the energy transition, because of their low energy requirements and ability to precisely manage flows of gases like methane that might otherwise be vented to the atmosphere.
As production in the Permian basin continues to rise in the coming years, it is companies that embrace this kind of technology that will achieve the greatest success and maintain their social license to operate in a warming world. WO
REFERENCES
CHRIS HARDY is head of Strategy for Oil & Gas at Rotork. With more than 18 years of experience in the energy sector, Hardy is responsible for executing Rotork's upstream strategy. He holds a bachelor's degree in business administration, a master's degree in finance, and an MBA in finance and strategic management from The Wharton School, University of Pennsylvania.