Understand the chain
Explainers
Every page here opens with a one-sentence definition, explains the mechanism rather than the marketing, and ends with assets from the tracker so the idea connects to real projects.
Start here
- How LNG worksLiquefied natural gas is natural gas chilled to about minus 162 degrees Celsius, at which point it becomes a liquid roughly 600 times smaller than the gas, so it can be shipped where no pipeline runs.
- The LNG value chain end to endThe LNG value chain is the sequence of production, treatment, liquefaction, shipping, regasification and distribution that moves natural gas between markets no pipeline connects, at an end-to-end energy cost of roughly 10 to 20 per cent of the gas itself.
- The physical properties that govern everythingLNG is a colourless, odourless cryogenic liquid at about minus 162 degrees Celsius, roughly 45 per cent as dense as water, which expands about 600 times on returning to gas and burns only as a vapour mixed with air in a narrow range of concentrations.
- Why minus 162 degrees, and what the cold costsMethane has a critical temperature of about minus 82.6 degrees Celsius, above which no pressure will liquefy it, so LNG production means chilling gas below its atmospheric boiling point of about minus 162 degrees at an energy cost of roughly 8 to 12 per cent of the feed.
Reading the numbers
- Mtpa, bcm and cubic metresLNG capacity is quoted in three incompatible units, and the two conversions that matter are 1 million tonnes a year equals about 1.36 billion cubic metres of gas a year, and 1 cubic metre of liquid equals about 600 cubic metres of gas.
- Reading a capacity figure without being misledAn LNG capacity figure is only meaningful alongside three qualifiers — which unit it is in, which project status it describes, and whether it is a design nameplate or actual output — and most disagreements between sources come from one of those being dropped.
- What terminal status actually meansA project status describes how far an LNG terminal or train has progressed, and the gap between proposed and operating is the single most misread number in the industry.
Making it
- Feed gas: where it comes from and what is in itFeed gas is the raw natural gas delivered to a liquefaction plant before treatment, and its composition determines the size and content of the treatment section as well as what co-products the plant can sell.
- Gas treatment: acid gas, mercury, water and heaviesGas treatment is the sequence of processes removing carbon dioxide, water, mercury, sulphur compounds and heavy hydrocarbons from feed gas before liquefaction, because each of them would freeze, foul or damage the cold section.
- Liquefaction trains explainedA liquefaction train is one complete, self-contained refrigeration line that chills treated natural gas until it condenses, and a large modern train produces roughly 5 to 8 million tonnes of LNG a year.
- The refrigeration cycles: C3MR, DMR, AP-X and SMRA liquefaction refrigeration cycle is the closed loop of compression, cooling and expansion that removes heat from feed gas, and the commercial processes differ mainly in how many loops they use and what refrigerant is in each.
- Coil-wound and plate-fin heat exchangersThe main cryogenic heat exchanger is where feed gas finally condenses, built either as a coil-wound exchanger of tubing spiralled around a core or as a block of brazed aluminium plates and fins.
- Drivers: gas turbines, electric motors and the gridA driver is the machine turning a liquefaction plant's refrigerant compressors, either a gas turbine burning part of the feed gas or a large electric motor drawing power from a grid or on-site generation.
Export terminals
- Loading jetties and the export terminal layoutAn LNG export terminal is laid out as a sequence from feed gas reception through treatment and liquefaction trains to storage and a marine loading jetty, with separation distances between blocks set by hazard analysis.
- Storage tanks, 9% nickel and high-manganese steelAn LNG storage tank holds liquid at close to atmospheric pressure in an inner shell of cryogenic alloy, surrounded by insulation and, in the full containment design, an outer concrete wall capable of containing the entire contents.
- FLNG explainedFloating liquefaction, or FLNG, is a complete LNG plant built on a ship-shaped hull and moored over or near a gas field, so gas is liquefied at sea and loaded straight onto carriers without any onshore terminal.
Import and regasification
- What an import terminal actually doesAn LNG import terminal receives cargo from a ship, stores it as a cryogenic liquid, pumps it to pipeline pressure and warms it back into gas for delivery into a grid.
- FSRU versus onshore regasificationAn FSRU is a ship that stores LNG and turns it back into gas while moored, doing the job of an onshore import terminal without the onshore construction.
- Vaporiser types: ORV, SCV and ambient airA vaporiser is the heat exchanger that turns pressurised LNG back into gas at an import terminal, using seawater, burned gas or ambient air as the heat source.
- Send-out, peak shaving and the grid connectionSend-out is the rate at which an import terminal delivers regasified LNG into a pipeline network, and it is the capacity figure that governs what the terminal can actually do.
- Storage operations: ageing, stratification and rolloverLNG storage operations are the monitoring and filling practices that keep stored LNG mixed and of known composition, preventing the stable density layers whose sudden inversion is called rollover.
Beyond the grid
- Truck loading, ISO tanks and small-scale distributionSmall-scale LNG distribution moves liquid past the import terminal by road tanker, rail and ISO container to satellite storage plants, industrial users and fuelling stations beyond the pipeline grid.
- Break bulk and island supply chainsBreak bulk is the practice of receiving a full LNG cargo at a hub terminal and redistributing it in smaller parcels by small carrier, barge or road to markets too small or too shallow for a conventional ship.
The ships
- LNG carrier anatomyAn LNG carrier is a ship built around insulated cargo tanks that hold liquefied gas at minus 162 degrees, with an engine able to burn the cargo vapour that inevitably boils off during the voyage.
- Ship classes: conventional, Q-Flex, Q-Max and small-scaleLNG carriers fall into recognised size classes running from small-scale vessels under 30,000 cubic metres, through the 174,000 cubic metre conventional standard, to the 266,000 cubic metre Q-Max ships built for Qatar.
- Membrane versus Moss tanksCargo containment is the system that holds LNG at minus 162 degrees inside a ship, and it comes in two families: membranes, which are thin barriers supported by the hull, and free-standing tanks, which carry their own load.
- Containment II: Moss spheres and SPB tanksA free-standing LNG tank is one that supports its own weight and cargo loads rather than transferring them to the ship's hull, the two commercial designs being the Moss spherical tank and IHI's prismatic SPB tank.
- Insulation, Invar and holding the cold chainLNG containment insulation is the layered barrier that limits heat leaking into the cargo, and Invar is a nickel-iron alloy used in one membrane design because it barely contracts when the cargo cools it.
Machinery
- Propulsion I: steam turbines and why they enduredSteam turbine propulsion drives an LNG carrier by raising steam in boilers that can burn cargo boil-off gas, fuel oil, or any mixture of the two, and turning a turbine geared to a single propeller shaft.
- Propulsion II: DFDE and TFDE, the dual-fuel eraDual-fuel diesel electric propulsion uses medium-speed engines burning either boil-off gas or liquid fuel to generate electricity, which drives electric propulsion motors rather than a directly coupled shaft.
- Propulsion III: ME-GI, X-DF and two-stroke gas injectionME-GI and X-DF are the two families of low-speed two-stroke marine engine burning natural gas, differing in whether gas is injected at high pressure late in the cycle or admitted at low pressure and premixed.
- Boil-off and reliquefactionBoil-off is the small fraction of an LNG cargo that evaporates each day as heat leaks into the tanks, and it is what keeps the rest of the cargo cold.
- Reliquefaction, subcooling and when they payReliquefaction is the process of cooling boil-off gas back into liquid and returning it to the cargo tanks, and subcooling is the partial version that chills the vapour enough to reduce cargo loss without eliminating it.
Operations
- The voyage cycle: laden, ballast, heel and the returnThe LNG voyage cycle is the round trip of a laden leg carrying cargo and a ballast leg returning empty, with a small heel of LNG retained throughout to keep the tanks cold enough to load again on arrival.
- Cooldown, gassing up and the first cargoCooldown is the controlled chilling of warm cargo tanks by spraying LNG into them, and gassing up is the preceding step of replacing inert gas with methane vapour so no carbon dioxide remains to freeze.
- The ship–shore interface: arms, ESD and compatibilityThe ship-shore interface is everything that must be compatible between a vessel and a terminal before LNG can be transferred, from manifold height and spacing to the linked emergency shutdown systems on both sides.
- Ship-to-ship transfer and floating storageShip-to-ship transfer is the movement of LNG directly between two vessels moored alongside one another, used for transshipment, replenishing floating storage, and breaking a full cargo into smaller parcels.
- Custody transfer: gauging, and who owns the errorCustody transfer is the measurement determining how much energy passed between seller and buyer at loading or discharge, calculated from tank level, liquid temperature and density, and a laboratory analysis of the cargo composition.
The shipping business
- Chartering: spot, time charter and tollingLNG chartering is the hire of a carrier, either for a single voyage at a spot rate or for a period under a time charter at a daily rate, with the charterer directing the vessel and the owner supplying and crewing it.
- What freight rates mean and why they swingAn LNG freight rate is the daily cost of hiring a carrier, assessed by shipbrokers for standard routes and vessel types, and it swings violently because fleet supply cannot respond within the time demand changes.
- Who builds LNG shipsLNG carriers are built by a very small group of shipyards, concentrated in South Korea, China and Japan, because the cargo containment work demands skills and facilities that take years to develop.
- Crewing and competency on a gas carrierCrewing an LNG carrier requires officers holding STCW gas tanker endorsements earned through both training and documented service on gas carriers, a qualification pool that expands more slowly than the fleet it has to staff.
- Ice-class carriers and the Arctic routesAn ice-class LNG carrier is a vessel strengthened to operate independently in sea ice, the highest commercial grade being Arc7 ships able to break ice astern, built to serve Arctic export projects along the Northern Sea Route.
- LNG as marine fuel: bunkering and the supply chainLNG bunkering is the supply of liquefied natural gas as fuel to ships rather than as cargo, delivered by bunker vessel, road tanker or shore pipeline, and governed by its own codes and standards.
The bigger picture
- LNG against pipeline gasA pipeline delivers gas at lower cost than LNG over land up to roughly two to four thousand kilometres, beyond which liquefaction wins, and across any significant body of deep water LNG usually wins at any distance.
- LNG and maritime chokepointsA maritime chokepoint is a narrow strait or canal that a large share of seaborne trade must pass through, and LNG exposure to them depends entirely on which exporting region supplies which importing market.
- A short history of LNGLNG began as a way of storing gas for winter peaks in the 1940s, became a traded commodity with the Methane Pioneer's Atlantic crossing in 1959 and the first commercial trade from Algeria in 1964, and has grown into a global market reshaped in turn by Qatar, Australia and US shale gas.
Safety
- Why LNG behaves the way it does in an incidentAn LNG spill boils rapidly on contact with warmer surroundings, forms a cold vapour cloud that is initially denser than air, and becomes flammable only where that vapour has diluted into a narrow concentration band.
- Rapid phase transition, pool fires and vapour dispersionA rapid phase transition is a physical explosion caused by LNG vaporising almost instantaneously on contact with water, with no combustion involved, distinct from a pool fire, which is a fire burning above a spreading pool of spilled LNG.
- The IGC Code and what SIGTTO doesThe IGC Code is the International Maritime Organization's mandatory code for ships carrying liquefied gases in bulk, and SIGTTO is the industry association whose operational guidance is treated as the practical standard alongside it.
- Terminal siting and exclusion zonesAn exclusion zone is the area around an LNG facility within which development is restricted, calculated from thermal radiation and vapour dispersion modelling of the credible worst-case spill scenarios.
Emissions
- Methane slip and the emissions argumentMethane slip is unburned methane passing through an engine into the exhaust, and it matters disproportionately for climate impact because methane traps far more heat than the carbon dioxide it would have become.
- Lifecycle emissions: the honest versionLifecycle emissions accounting sums greenhouse gas output across production, processing, liquefaction, shipping and regasification through to final combustion, and estimates vary widely mainly because upstream methane leakage is poorly measured.
Reading the data
- What terminal status actually meansA project status describes how far an LNG terminal or train has progressed, and the gap between proposed and operating is the single most misread number in the industry.
- Why capacity figures disagree between sourcesLNG capacity figures disagree between sources mainly because of differing unit conventions, differing project statuses included in a total, nameplate against actual output, and how tracker compilers resolve conflicting primary sources.
- Ownership, parents and why they differOwnership, operatorship and parent-company control are three distinct relationships an LNG asset can have with a firm, and a tracker recording all three separately is describing three different kinds of influence, not redundant detail.
- What a tracker can and cannot tell youAn infrastructure tracker like the Global Gas Infrastructure Tracker reports what public sources say about a project at a point in time, which is a different and narrower thing than reporting what is objectively true about the project right now.
- How to cite this site, and what to check firstCiting this site correctly means attributing the underlying Global Gas Infrastructure Tracker data to Global Energy Monitor by name and release, while separately attributing any grouping, computation or written explanation original to this site.
Buying and selling
- How LNG is actually bought: SPAs, tenders and spotLNG is bought and sold through long-term sale and purchase agreements negotiated bilaterally, medium-term supply secured by competitive tender, and single cargoes traded on the spot market at a price agreed close to delivery.
- Oil indexation, slopes and the S-curveOil indexation prices LNG as a formula tied to a crude oil marker, typically a percentage slope applied to the oil price plus a constant, with an S-curve variant flattening the formula's response at extreme prices.
- Hub pricing: JKM, TTF and Henry HubJKM, TTF and Henry Hub are gas price benchmarks for north-east Asia, north-west Europe and the United States respectively, each reflecting a distinct regional supply and demand balance rather than a single global LNG price.
- Destination clauses and cargo diversionA destination clause is a contract term restricting where a purchased LNG cargo may be resold or delivered, historically used by sellers to prevent buyers reselling contracted gas into markets the seller served directly.
- Arbitrage: when a cargo changes oceanLNG arbitrage is the redirection of a cargo from one regional market to another to capture a price difference, executed only when the destination's netback value exceeds the origin's by more than the cost of shipping there.
Financing a project
- Tolling, offtake and how projects are financedLNG project financing depends on offtake agreements committing buyers to future volumes before construction, structured either as traditional sale contracts where the seller owns and prices the gas, or as tolling agreements where the customer owns the gas and pays only a processing fee.
- Take-or-pay and the shape of the obligationTake-or-pay is a contract term obliging the buyer to pay for a specified minimum volume of LNG regardless of whether it actually takes delivery of that volume, giving the seller revenue certainty independent of the buyer's actual demand.
- Reading a final investment decisionA final investment decision is the point at which a project's owners commit the capital and sign the construction contracts to build it, converting a proposal into a funded commitment with binding obligations behind it.