The electric submersible pump, or ESP, is the artificial-lift method of choice when a well needs to move large volumes of fluid. It is a multistage centrifugal pump that runs thousands of feet downhole, driven by an electric motor on the end of a power cable. This guide explains what an ESP is, how its parts work together, and where it fits among lift methods.
ESP in one line: An electric submersible pump (ESP) is a multistage centrifugal pump installed downhole and driven by a submerged electric motor, used to lift high volumes of fluid from an oil well to the surface. It is a high-rate artificial-lift method.
An ESP system is a string of components run on the production tubing. At the bottom is a submersible electric motor, above it a seal (protector) section that isolates the motor oil from wellbore fluid and handles thrust, then an intake or gas separator, and above that the pump - a stack of many centrifugal stages, each adding pressure (head). Power reaches the motor through an armored cable clamped to the tubing.
Each pump stage takes fluid from the stage below and adds a little head; stacking dozens or hundreds of stages builds the pressure needed to lift fluid the full depth of the well. Because it is centrifugal, an ESP is efficient at high flow rates but sensitive to free gas and solids, which is why gas handling at the intake matters.
At surface, ESPs are usually run from a variable speed drive (VSD, also called a VFD), which lets the operator tune pump speed to the well's inflow rather than running fixed-speed. The drive protects the motor and lets the system ramp gently on startup. A switchboard or the drive itself provides overload and underload protection.
ESPs shine on high-volume wells - waterfloods, prolific offshore wells, and high-water-cut producers - handling rates from hundreds to tens of thousands of barrels per day. Their weakness is that a downhole failure means a costly workover to pull and replace the string, so run life and monitoring are central to ESP economics.
A downhole gauge typically reports pump intake pressure, discharge pressure, motor temperature, and vibration, while the drive reports motor current, frequency, and load. Watching these together reveals gas locking, pump wear, plugging, and impending failure long before the pump quits, which protects run life.
SCADA pulls these signals from the drive and gauge and trends them. A cloud-native platform such as Merobix reads VSD and controller data over Modbus, so intake pressure, motor load, and frequency for every ESP in a field are visible and alarmed remotely.
A submerged electric motor drives a multistage centrifugal pump downhole. Each stage adds pressure, and stacking many stages builds enough head to lift fluid to surface. Power is delivered through an armored cable, and a surface variable speed drive controls pump speed.
ESPs suit high-volume wells - waterfloods, prolific offshore producers, and high-water-cut wells - where rates run from hundreds to tens of thousands of barrels per day. They are less suited to very low-rate or extremely gassy wells, where rod pumps, gas lift, or plunger lift fit better.
Common causes include gas locking, abrasive solids wearing the stages, scale or plugging, high downhole temperature stressing the motor, and electrical failure of the cable or motor. Monitoring intake pressure, motor load, and temperature helps catch problems before the pump fails.
This page references the protocol specifications published by the organizations below. Editions, product capabilities, and documentation change over time - confirm current requirements and specifications directly with the source.
Last reviewed: July 27, 2026. Merobix is not affiliated with, endorsed by, or sponsored by these organizations; their names are used only to identify the standards and products discussed.
Merobix reads your field devices into a cloud SCADA - the real thing behind these terms, live in days from any browser.