Electrical Submersible Pumps (ESPs) have been manufactured since 1928 [1], and since then, much has changed regarding the equipment and its application scenarios. When they were first invented, ESPs were used in onshore fields for short tie-backs. Since then, the application scenario has changed significantly. Conversely, for Petrobras, they are mostly used in deep-water offshore fields with wet Christmas trees and long tie-backs, in most cases, inside subsea equipment (such as MoBo [2] or skid-mounted ESP [3]).
For the latter scenario, denominated as critical wells in Petrobras, the resources and costs involved in installing a new ESP and retrieving a faulty one are very different from those in the onshore scenario. Considering the rig costs and deferred production, for a subsea well, one operation might cost more than 30 million dollars. In the case of a premature failure that requires retrieving the faulty equipment and installing a new one, the impact is hence more than 60 million dollars. Once again, this is a very different scenario from the onshore scenario.
The world’s first ESP in a subsea well was installed by Petrobras in RJS-221 (Carapeba field) in 1994, in shallow water. Following that, in deep water, Petrobras installed an ESP in RJS-477 (Albacora Leste field) in 1998 [4]. From 1998 to around 2008, Petrobras experienced numerous premature failures with ESPs. The situation was so dire that there was even consideration given to abandoning the use of ESPs in favor of gas lift. This would result in lower production but also reduced deferred production and decreased workover costs.
