Overview
During a recent IMR campaign at Åsgard B, Equinor used the Liberty™ E-ROV System to support critical pigging and spool replacement activities in approximately 300-meter water depths.
Operated entirely from Oceaneering’s Onshore Remote Operations Center (OROC) in Stavanger, the system provided continuous continuous subsea presence, real-time data, and operational assurance without requiring personnel offshore between deployment and recovery.
Unlike conventional IMR campaigns that rely on dedicated vessel support throughout execution, the Liberty™ E-ROV System remained subsea for 56 days, enabling safe and efficient operations while significantly reducing vessel dependency and offshore exposure.
Our Plan
Equinor used the Liberty™ E-ROV System under a long-term contract for seven years prior to this campaign.
For this scope, the system was deployed and recovered using a vessel of opportunity before operating independently on the seabed for 56 days.
Throughout the campaign, the system served as a critical operational assurance platform. The system monitored isolation tools acting as secondary barriers, supported active pigging tracking operations, detected potential leaks during testing activities, and verified barrier integrity throughout tie-in operations. By providing live, verified subsea data, the system enabled informed decision-making during critical phases of the project. The project’s success required seamless collaboration between Equinor, onshore operations teams, and project partners, enabling improved decision-making and operational responsiveness.
After 56 days and a total of 1,344 subsea operating hours, the system successfully completed the campaign. The vehicle returned to the docking station, enabling efficient retrieval following the long-duration deployment.
Value Delivered
The project showed how resident subsea technology can be used to execute complex IMR activities without continuous vessel support or offshore personnel.
Continuous subsea presence, real-time operational visibility, and remote control from shore enabled safer and more efficient execution while reducing operational complexity and vessel dependency.
The campaign demonstrated how resident technology can extend both operational flexibility and remote decision making. Critical decision-making personnel were integrated into operations from onshore. The isolation specialist responsible for validating well isolation activities during the scope was located at our Onshore Remote Operations Center (OROC) in Stavanger, maintaining operational assurance and supporting safe execution without the need for additional offshore personnel. In addition, the Liberty™ E-ROV System’s continuous presence enabled essential monitoring and verification activities to continue during periods when weather conditions restricted surface vessel operations, helping Equinor maintain project momentum and reduce schedule risk.
Following 56 days of uninterrupted operation, the Liberty™ E-ROV System was recovered with a 16% battery reserve remaining, demonstrating the viability of long-duration battery-powered resident operations.
Key results included:
- 56 days of uninterrupted subsea operation
- 1,344 operating hours completed from shore
- No offshore personnel required during operations
- Vessel required only for deployment and recovery, reducing emissions
- Key specialist roles relocated to OROC
- Resident deployment helped avoid potential delays related to weather and vessel-based equipment
- 16% battery reserve remaining at recovery