Reducing cost and emissions during drilling

COSL’s ‘Energy Control’ project analysed historical data on estimated maximum power consumption derived from COSL’s semi-submersible DP3 rigs COSLPromoter and COSLInnovator and found that it would be possible to remove the need to run all six of its 4,800kW Wärtsila Vasa 12V32 diesel during drilling operations.

NOV then used this data to create new software for optimal energy usage whilst Kongsberg Maritime developed the most efficient means of controlling onboard energy production and distribution.

The project, supported by the NOx Fund, a Norwegian Government initiative, established that the rig would still be able to carry out full drilling operations using only three of its diesel generators, reducing fuel consumption each year by around 2,300 tonnes and cutting CO2 and NOx emissions by 7,300 and 125 tonnes respectively.

“We can now accomplish complete drilling operations on COSLPromoter and COSLInnovator while using less than 20 tonnes of fuel per day, with scope to reduce that figure even further,” said COSL project leader, Torfinn Kalstø. “We also have the reassurance of knowing that the spare generators are on hand should any changes in conditions or circumstances require them to be used.”

Kongsberg Maritime’s DP system technology eradicates spikes thus yielding a significant portion of the overall fuel saving whilst a Kongsberg information management system collates performance data so that ongoing improvements can be verified against benchmarked data.