Low Carbon Remote Power - Basis for Decarbonization of Drilling Operations

Abstract Drilling rigs operations are cost intensive and require movement from one drilling location to another. Traditionally, diesel generators are used, however, these operate at low loads and efficiency leading to high costs and emissions. An Upstream Operator in Oman has embarked on a journey to reduce 25% of its emissions by 2030 and net-zero by 2050. The baseline energy intensity for the Upstream Operator is 45.44 kWh/BOE and emission intensity is 12.37 kgCO2e/BOE. Drilling operations have a significant contribution to emissions in upstream with energy intensity being 4kWh/BOE and emission intensity being 1.1 kgCO2e/BOE and is one of the primary focus areas for decarbonization. Through Energy Efficiency program, the aim is to follow a decarbonization roadmap for drilling operations including options for low carbon power focusing on two areas: diesel engine management and hybrid power. Diesel Engine Management: The primary energy consumers in a rig are the top-drive, draw works and the mud pumps, which contribute 80-90% of consumption. The operation of these equipment is irregular, hence, rig operators keep all engines in operation to cater to the maximum load. For most of the time, loading of the engine is low, ~20-30 where efficiency could be as low as 20%, leading to high cost and emissions. Engine management applications provide a simple way of ensuring operation at highest efficiency by enabling the operator to turn off engines when under low load. This will ensure the generators are loaded ~50-60% with better efficiency, ~30-40%. For drilling, this can reduce energy intensity by ~0.25 kWh/BOE and emission by ~0.07 kgCO2e/BOE. Hybrid Power: Energy storage such as batteries can be used to store energy from engines to operate these at maximum efficiency and turn off when the batteries are fully charged. The irregular power demand is met by batteries. This can provide 10-30% energy and emissions reduction. For the drilling operation, this can reduce the overall energy intensity by ~0.51 kWh/BOE and emission by ~0.14 kgCO2e/BOE. Rig camps run on diesel generators with low load due to seasonal variation in demand. Using solar+diesel hybrid can easily reduce up to 30% of the energy and emissions from rig camps. This can reduce the overall energy intensity by ~0.1 kWh/BOE and emission by ~0.03 kgCO2e/BOE. The energy excellence program for drilling will be able to achieve cost, energy and emissions reduction and help the Operator achieve its decarbonization target. The paper will review the implementation of low carbon power for the drilling operations and highlight benefits and challenges encountered during execution. It will provide insight into business models to provide low or no CAPEX opportunities to fast track these technologies for rigs. This study will provide a basis for other operators to develop and follow a similar program to help reach their decarbonization goals.