LNG Book

FPSO topside process

Onshore LNG plant cost

  • Breakdown of costs for three existing LNG operations

: Stranded wellhead gas price through liquefaction, marine transportation, and regasification operations

[table id=26 /]

FLNG opening more gas to development

  • Accesses gas unsuitable for baseload development
  • Eliminates pipeline & loading infrastructure costs
  • Reduces security and political risks
  • Constructed in controlled

shipyard environment

  • Can relocate facility

upon field depletion

Two distinct development paths emerging

[table id=27 /]

Marine settings present technical challenges

  • Waves, wind and currents
  • Process equipment performance
  • LNG storage “sloshing”
  • Open-water LNG transfers
  • Pretreatment requires up to 50% of available deck area
  • Favors feed gas with low levels of inerts and impurities
  • Condensates and LPGs increase processing, storage and offloading demands

Liquefaction choices far from mature

  • Need simple, robust and compact liquefaction solutions
  • Single mixed refrigerant cycles
  • Gas expander-based cycles
  • Concerns
  • Process efficiencies
  • Scale-up performance
  • LPG refrigerant storage
  • Marine performance and reliability

Economics in uncertainty

  • Development costs look competitive, but require further critical analysis
  • Reserves depletion relevant to project’s economic performance
  • No long, slow depletion profiles
  • Additional drilling to sustain field’s production plateau; maintain feed gas pressures
  • FLNG relocation not necessarily easy
  • Balance costly, time-consuming retrofits vs. sub-optimal performance
  • Abandonment timing

Construction risk-sharing must be addressed

  • Risk allocation between the shipbuilder, process vendor, and EPC contractor needs definition
  • More construction risks will ultimately rest with project owners or LNG buyers
  • EPC contractors don’t have the balance sheet to bear completion or performance risks for emerging technologies
  • Licensing agreements for jointly developed technologies

Legal/regulatory landscape can affect design

  • Marine setting brings FPSO-type legal frameworks into play
  • Which national legislation, flag state regulations, class rules and international conventions apply?
  • FLNG approvals similar to those for LNG vessels
  • Some legal issues can affect design
  • Ship vs. static facility?
  • Is the vessel transporting gas?
  • Fulfilling Domestic Market Obligations
  • Local content requirements

Mandatory rules and regulations

  • In general same governing topside classification regulations as on other FPSOs:
  • DNV-OS-E201 Oil and Gas Processing Systems
  • DNV-OS-A101 Safety Principles and Arrangements
  • DNV-OS-B101 Metallic Materials
  • DNV-OS-C401 Fabrication and Testing of Offshore Structures
  • DNV-OS-D101 Marine and Machinery Systems and Equipment
  • DNV-OS-D201 Electrical Installations
  • DNV-OS-D202 Instrumentation and Telecommunication Systems
  • DNV-OS-D301 Fire Protection
  • API RP 14C Safety Analysis
  • API RP 520 Sizing, Selection and installation of Pressure Relieving Devices
  • API RP 521 Guide for Pressure Relieving and Depressurizing Systems
  • Novel LNG FPSO mandatory rules and regulations
  • DNV-OSS-309: Verification, certification and classification of gas export and receiving terminals
  • IMO IGC Code: International Code for the Construction and Equipment of Ships Carrying Liquefied Gases in Bulk

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