Towards Realizing Net Zero Carbon Emissions for Sustainability of Existing and Aging Offshore Facilities

Abstract

Amidst global push towards sustainable energy, efforts to drive down greenhouse gas (GHG) emissions towards net zero across all upstream assets and new developments are expected to intensify. This task has proven to be far more challenging for existing, aging offshore facilities both technically and commercially. This paper will share various fit-for-purpose options identified through rigorous front-end loading (FEL) processes which can be implemented on existing, aging facilities to accelerate and realize sustainable GHG emission reduction efforts across all business value chain. Essence of decarbonization is in the reduction of carbon dioxide (CO2) and hydrocarbon emissions. Apart from carbon tax inclusion in decision making, proactive directives in zero continuous hydrocarbon venting and flaring in upstream facilities while maximizing renewable energy applications has already set the momentum. Beyond that, lies the task of developing sustainable carbon abatement strategies for existing, aging facilities. Up to eight (8) concepts were explored through feasibility study at FEL assessing the extent of brownfield modification, emissions reduction, and associated costs. Concepts range from cost-efficient vent to flare conversions to CAPEX-intensive gas injection and sequestration solutions. Options with monetization potential such as floating compressed natural gas (FCNG), liquid or condensate recovery system (CRS) and gas liquefaction are within consideration as well. Value improvement beyond facilities design life is influenced by the sustainability of solutions introduced. There are 25 tons of CO2e in every part of methane (CH4) released in vent gas, which is a common design for offshore facilities aged more than 30 years. Efforts in emissions reduction is therefore deemed most suitably carried out in both a short- and long-term manner, which is replicable regardless of a facility's age. Short term, fit-for-purpose solution of converting existing vent stacks into flare stacks with cyclone separator-caisson system is projected to be able to significantly reduce GHG emissions up to 70% in the span of 3 years. Leading towards net zero, mid and long-term efforts through gas injection and sequestration including monetization strategies will be more sustainable as they demonstrate potential of up to 95% GHG emissions reduction within field life. Particularly for monetization opportunities such as pipeline export, CNG, CRS and gas liquefaction, area development strategy is recommended to establish economy of scale. Ability to synergize carbon abatement with capital projects innovatively to achieve positive economic returns while transitioning into a global environment of sustainability is crucial. Decarbonization efforts especially for existing, aging upstream facilities requires firstly, a strong managerial aspiration in the sustainability agenda; Secondly, expertise of operations to balance life cycle costs against carbon abatement investments. Strategies outlined in this paper share insights on how decarbonization efforts can be streamlined for effective execution towards net zero carbon emissions target.