Decarbonization Strategies to Reduce GHG Emissions on the All Electric FPSO

Abstract

Abstract This paper presents a set of technologies and optimizations implemented in the All Electric FPSO, the largest PETROBRAS’ design, that was conceived to operate in Atapu and Sépia fields and will become into P-84 and P-85 FPSOs, respectively. This design was done to increase the Pre-Salt production, add more value to its reserves and minimize greenhouse gas (GHG) emissions. All Electric concept considers all rotating process equipment to be driven by electrical motors. Based on this concept, the process plant configuration and the number of equipment trains were defined to comply with the flow capacities. The adoption of this new concept was possible due to proactive advocacy of PETROBRAS and other oil and gas companies for the revision of an environmental regulation that limited its use (CONAMA 382/2006). Moreover, other decarbonization solutions were selected and incorporated on the project based on MACC methodology and PETROBRAS's low carbon strategy. Considering the typical emissions of a FPSO, the technologies and optimizations were deployed on the main sources: power generation, flaring, venting and fugitives. Some reduction emission initiatives were implemented for the first time in a FPSO of large capacity, such as: all-electric plant concept, deeper seawater intake system, cargo tanks gas blanketing and recovery system and variable speed control on water injection pumps. Moreover, known technologies such as flare gas recovery system, closed drainage gas recovery system, cogeneration, low fugitive emission valves, and CCUS-EOR etc. were also used on All Electric FPSO design. As a result, the GHG emission intensity achieved was estimated about up to 30% less than previous FPSO designs. Another accomplishment was the zero routine flaring and venting, based on World Bank initiative, which PETROBRAS is committed. Finally, all these initiatives are significant to the company achieve its goals, maximizing value and producing oil and gas with reduction of GHG emissions. The All Electric FPSO design is an example of how an energy efficiency approach could achieve a reduction in GHG emissions. The lessons learned during the development of this design contribute to broaden the knowledge for oil and gas industry decarbonization.