COSL Drilling Europe has used thousands of data points and Kongsberg Maritime’s power management technology to reduce fuel use and emissions across its North Sea rig fleet. The results show how better operational data can reshape energy management without compromising drilling performance.
COSL Drilling Europe has cut fuel consumption and emissions by more than 50 per cent across its North Sea fleet by using digital data to manage energy consumption more precisely.
The offshore rig operator worked with Kongsberg Maritime on an advanced energy control system that has enabled its semi-submersible rigs to operate with far less generating capacity than previously thought necessary.
The scale of the change is substantial. COSL says it has saved around 70 million litres of diesel across its rigs, with fuel savings of about $30,000 per day per rig compared with traditional operations.
The system has also changed how the company approaches redundancy. Rigs that once routinely operated six generator sets can now carry out the same work with two, or even one under certain conditions.
“We changed our total energy management system,” says Torfinn Kalstø, former ICT/OT & Energy Management Lead, COSL Drilling Europe. “Today, we can perform the same operations with as little as one genset, when previously we ran six, and still deliver full performance.”
COSL says the efficiency gains have not affected drilling performance. Thruster use has also fallen by around 80 per cent, with power scaled according to operational requirements rather than running continuously.
The results came from gaining a much clearer picture of how rigs actually consume energy. “We soon found that we were utilising less than 10 per cent of the actual available energy on board the rig, so there was huge room for improvement,” Kalstø says.
COSL CEO Frank Tollefsen says the data has also influenced how future rigs could be designed. “If we were designing these rigs today, we would likely install only half the generating capacity,” he says.
The case illustrates a practical lesson for shipowners and offshore operators: digitalisation can deliver measurable savings when operational data is connected directly to day-to-day decisions. Rather than adding more technology, COSL has used data to question assumptions about how much power its assets actually need.
