UK ETS for Shipping

Background and history

The UK ETS as the post-Brexit replacement

The United Kingdom took part in the EU Emissions Trading System (EU ETS) from its launch on 1 January 2005 until the UK left the European Union on 31 January 2020. Through the withdrawal transition period the UK kept trading EU allowances while building a domestic successor. The replacement is the UK ETS, set up by the Greenhouse Gas Emissions Trading Scheme Order 2020 (SI 2020/1265), operative from 1 January 2021.

The UK ETS is run by the UK ETS Authority, and the word “Authority” carries weight here. It isn’t a single department; it’s a standing partnership of four governments: the UK Government (the Department for Energy Security and Net Zero, DESNZ), the Scottish Government, the Welsh Government, and the Department of Agriculture, Environment and Rural Affairs (DAERA) for Northern Ireland. Each constituent administration has to agree before the scheme changes shape. That structure matters for maritime, because the inshore fleet, the island ferries, and the offshore support sector sit squarely inside devolved interests.

At launch the scheme covered heavy industry, power generation, and aviation, roughly 25% of UK territorial emissions on the Authority’s own reckoning. The allowance unit is the UK Allowance (UKA), each worth one tonne of CO2 equivalent. The cap declines on a path the Authority describes as net-zero consistent; from the 2024 scheme year that path was tightened to align with the UK’s legally binding 2050 net-zero target. Maritime was outside scope at launch. The IMO had not yet adopted its mid-term measures, the EU ETS for shipping had not been agreed, and the UK preferred to watch the monitoring methodology settle before pricing the sector.

The maritime scope-expansion consultation

The Authority consulted on bringing maritime into scope and then published its main response setting the final policy detail. The headline decision: domestic maritime emissions enter the UK ETS from 1 July 2026 for ships of 5,000 GT and above. The Authority chose 5,000 GT to mirror the threshold used by the existing UK Monitoring, Reporting and Verification (MRV) regime and the EU ETS, so the same vessels already counting their carbon now have to surrender against it. A review of the threshold is scheduled for 2028 to weigh whether to pull it lower toward the 400 GT figure the EU is studying.

What’s in scope is narrower than some operators feared and broader than others hoped. The response covers “emissions from domestic voyages on a ship-activity basis, as well as all in-port emissions in the UK.” A domestic voyage is one that starts and ends at UK ports. In-port emissions, the carbon a ship burns at berth running auxiliary engines and boilers, count in full regardless of where the next voyage goes. International voyages stay out of the domestic phase entirely; they’re the subject of a separate consultation discussed below.

The legislative and strategy basis

The cap addition and the surrender obligation are net-zero-anchored rather than picked for revenue. The Authority drew the maritime trajectory from the Department for Transport’s Maritime Decarbonisation Strategy, and it added 9,323,546 allowances to the UK ETS cap to account for the new sector. That figure isn’t rounded for presentation; it’s the modeled net-zero-consistent emissions volume for domestic maritime over the relevant period, and the Authority was explicit that scope expansion mid-phase has to come with a matching cap adjustment to keep cap integrity intact. Without the addition, bringing maritime in would have squeezed the existing power, industry, and aviation participants by shrinking the allowances effectively available to them.

The Authority also confirmed the legal architecture sits on the 2020 Order as amended, not on a fresh standalone statute, with the monitoring obligations building on the retained EU MRV Regulation (described next). Implementing secondary legislation operationalizes the 1 July 2026 start and the surrender mechanics.

Scope, ships, and exemptions

Ships covered

The threshold is 5,000 GT and above, applied to the ship performing eligible maritime activity, regardless of flag, on UK domestic voyages and at UK berths. A 4,900 GT coaster is out; a 5,100 GT ro-ro is in. Gross tonnage, not deadweight, is the gate, so a high-volume low-deadweight vehicle carrier can cross the line at a lower cargo capacity than a dense bulk carrier would.

Exemptions

The response carved out several categories rather than applying the threshold mechanically. Scottish island and peninsula ferries are exempt from the compliance obligation, recognizing that lifeline routes to communities without road alternatives can’t reprice carbon onto passengers without hitting the people the routes exist to serve. Fish-catching and fish-processing ships are excluded outright. Government maritime activity is out: military, customs, police, coastguard, emergency and medical, and research vessels. Offshore ships were not brought in on 1 July 2026; their inclusion is held to 1 January 2027 to align timing with the EU treatment of the offshore sector. These are deliberate policy carve-outs, not loopholes, and each is named in the Authority response rather than left to interpretation.

What “ship-activity basis” means in practice

Domestic-voyage emissions are attributed on a ship-activity basis: the operator works out the CO2 burned on qualifying voyages and at berth, converts other greenhouse gases to CO2 equivalent, and surrenders allowances against the total. The Authority confirmed the Global Warming Potential factors used for the conversion: CO2 counts as 1, methane (CH4) as 28, and nitrous oxide (N2O) as 265, on the 100-year basis. Methane and nitrous oxide are a material addition. The legacy UK MRV regime tracked CO2 only, so dual-fuel ships burning LNG, where unburned methane escapes through the engine, now carry a carbon cost on that methane slip at 28 times the mass.

Monitoring, reporting, and verification

The retained EU MRV regime as the spine

UK ETS maritime doesn’t invent a monitoring system. It rides on the existing UK MRV regime, which is the EU’s Regulation (EU) 2015/757 retained in UK domestic law after Brexit. The same per-voyage data spine that supports the EU MRV Regulation (fuel consumed, distance, time at sea, cargo carried, CO2 emitted) feeds the UK obligation. Operators already running this machinery for the EU regime or for the retained UK MRV reuse most of it.

The Authority listed five material changes from baseline UK MRV for ETS purposes, and they’re worth naming exactly because each one is a compliance task an operator has to action:

1. Wider scope, to capture in-scope voyages and ships that retained UK MRV didn’t reach.
2. Addition of methane and nitrous oxide, which UK MRV excluded.
3. Alignment with the UK ETS point of obligation, so the party that surrenders is defined the same way as in the rest of the scheme.
4. Regulator approval of monitoring plans, rather than the verifier-only assessment UK MRV used. The Authority signs off the plan, which is a tighter gate.
5. Per-operator rather than per-ship reporting, consolidating a fleet’s submissions to the operating company.

That fifth point is a real divergence from the per-ship logic of MRV and from the IMO Data Collection System. It pushes the reporting and surrender duty onto the operator as a single counterparty across its fleet, which simplifies the Authority’s enforcement target but obliges operators to aggregate across ships that may sit in different commercial arrangements.

Reporting and verification timeline

Verified annual emissions reports are due by 31 March following each scheme year. The verification step uses accredited verifiers, the same accreditation chain that supports EU MRV, so a ship subject to both regimes can keep one verifier relationship. The regulator-approval requirement on the monitoring plan means the plan itself has to clear the Authority before the data it governs is accepted.

The allowance, the cap, and the carbon cost

UK Allowance (UKA) and the auction

Each UKA equals one tonne of CO2 equivalent. Maritime operators get no free allocation. The Authority was direct: “the maritime sector will not receive free allocation,” and the full 9,323,546-allowance cap addition flows to auction rather than into any reserve, because allowances parked in a reserve would be inaccessible to a sector that buys everything it surrenders. So unlike a carbon-leakage-exposed steel plant that receives a free baseline, a shipping operator buys every UKA it needs, at auction or on the secondary market.

The carbon cost of a voyage is the surrendered tonnage multiplied by the UKA price. In inline terms, the annual UKA liability is $L = \sum_v (E_v \times f_v) \times P$, where $E_v$ is the CO2-equivalent emissions of qualifying activity $v$, $f_v$ is the coverage factor (1.0 for a domestic voyage or in-port emissions, 0.5 for a Northern Ireland to Great Britain leg), and $P$ is the UKA settlement or purchase price. There’s no allowance handed back; the whole liability is a cash cost that feeds straight into vessel operating expense. For a coastal tanker burning, say, 3,000 tonnes of fuel a year on UK domestic runs, the CO2 alone is on the order of 9,400 tonnes (using the standard heavy-fuel carbon factor near 3.114), and at a UKA price in the tens of pounds that’s a six-figure annual line. The companion UK ETS shipping liability calculator works the surrender total for a given activity profile and UKA price.

The cap and its net-zero trajectory

The 9,323,546 allowances added for maritime sit on top of the existing declining cap. The Authority’s stated principle is that any scope expansion during a trading phase must come with a cap adjustment that preserves cap integrity, so the new tonnage doesn’t dilute the scarcity the rest of the scheme depends on. The maritime slice tracks the Maritime Decarbonisation Strategy’s net-zero-consistent path, which means the maritime cap contribution is meant to fall over time the way the headline cap does, rather than holding flat.

Auction Reserve Price and the Cost Containment Mechanism

Two price controls shape what an operator pays. The Auction Reserve Price (ARP) is a floor below which auctioned UKAs won’t clear; the Authority set it at GBP 28 from April 2026 (raised from the earlier GBP 22), and from 1 January 2027 it adjusts yearly with inflation on the GDP deflator. The floor matters for maritime because it puts a hard lower bound on the carbon cost an operator can plan against, even in a soft market.

At the top end, the Cost Containment Mechanism (CCM) is the Authority’s intervention trigger. It can activate when the average secondary-market price for one allowance runs above three times the average price over the preceding two-year period for six consecutive months. If the CCM fires, the Authority has levers (releasing allowances, bringing forward auction volume) to damp the spike. The CCM is the UK analogue to the EU’s Market Stability Reserve, though the mechanisms differ in design and the UKA and EUA markets price independently.

Northern Ireland and the 50% deduction

The most distinctive feature of the domestic regime is the treatment of voyages between Northern Ireland and Great Britain. Under a literal application of the UK ETS, a Belfast to Liverpool sailing is a UK domestic voyage and would face 100% coverage. But the EU ETS for shipping covers 50% of emissions on voyages between an EU port and a non-EU port. A Dublin to Liverpool sailing, an EU-to-UK leg, therefore carries 50% EU coverage. Left unadjusted, a carrier moving goods into Liverpool would pay carbon on 100% of the emissions if it routed through Belfast but 50% if it routed through Dublin, an incentive to re-route through the Republic that serves no climate purpose and damages Northern Ireland ports.

The Authority’s fix is a 50% deduction from the UK ETS surrender obligation on voyages between Northern Ireland and Great Britain. The operator still monitors and reports the full emissions, but surrenders against half. That puts the Belfast to Liverpool leg on the same 50% footing as the Dublin to Liverpool leg, removing the re-routing pull. It’s a targeted parity measure, not a general discount, and it applies specifically to the Northern Ireland to Great Britain corridor, the one place where the UK domestic definition and the EU’s 50% international rule would otherwise collide.

This is the cleaner, narrower mechanism than the broad “Protocol carve-out” framing sometimes attached to it. There’s no claim that Belfast to Liverpool falls under EU ETS; it doesn’t. The point is purely to match the effective carbon-price burden so the two routings into Great Britain face the same cost.

Phase-in: double-surrender and the first scheme year

The first scheme year is a half-year: 1 July 2026 to 31 December 2026. To ease the transition, the Authority built in a double-surrender arrangement for the 2026 and 2027 scheme years. The deadline to surrender allowances for both the first scheme year and the 2027 scheme year is 30 April 2028. In effect, operators get a longer runway to acquire and surrender allowances for the opening period, surrendering for two scheme years at one deadline rather than facing a surrender obligation in spring 2027 for a half-year that only just closed.

From the 2028 scheme year onward, the standard UK ETS deadline applies: surrender by 30 April for the prior calendar year. So once the phase-in window closes, maritime sits on the same surrender calendar as the rest of the scheme.

International voyages: a proposal, not yet law

The domestic regime is confirmed. International voyages are not. The Authority opened a separate consultation proposing to bring international maritime voyages starting or ending in the UK into the scheme from 1 January 2028, applying to ships already in scope through their domestic activity or UK port calls. The proposed coverage mirrors the EU: operators would monitor and report 100% of emissions on an international voyage but surrender against 50%.

The 50% choice is deliberate alignment. The consultation states the aim that “100% of emissions are covered on voyages between the UK and the European Economic Area (EEA), from the combination of the UK ETS and EU ETS,” so the two regimes between them price the whole voyage once, with each side taking half and neither double-charging. The indicative cap adjustment for the first international phase (2028 to 2030) runs in the order of 4.7 to 5.0 MtCO2e a year for the 50% inclusion. None of this is settled. It’s a proposal in consultation, gated on the UK-EU emissions-trading linking talks under the Common Understanding the two sides reached, and the final shape depends on that negotiation and on the consultation responses. Treat the 2028 international date as a target, not a commitment.

How the carbon cost feeds vessel operating cost

For an operator, the UK ETS lands as a direct, non-recoverable operating cost on UK domestic trade. Because there’s no free allocation, the carbon cost can’t be offset by a free baseline the way an industrial emitter’s can; it’s a cash outflow tied to fuel burn. The cost has three drivers an operator can model: the in-scope CO2-equivalent tonnage (driven by fuel consumed on domestic voyages and at berth, plus the CH4 and N2O uplift for dual-fuel ships), the coverage factor (1.0 domestic, 0.5 on the Northern Ireland to Great Britain corridor), and the UKA price (floored by the ARP, capped in spirit by the CCM trigger).

Two operational levers cut the bill directly. Burning less fuel for the same transport work, through slow steaming or hull and propeller efficiency, cuts the tonnage one-for-one. Switching off auxiliary engines at berth by taking shore power cuts the in-port slice, which is fully in scope; the cold ironing and shore power pathway is therefore a UK ETS cost lever as well as a local air-quality one. Fuel switching is more complicated: a dual-fuel LNG ship cuts CO2 but adds a methane-slip cost at GWP 28, so the net carbon position depends on the engine’s slip characteristics rather than on the lower-carbon headline of the fuel.

For ships that also trade into the EEA, the UK cost stacks alongside the EU ETS cost and the FuelEU Maritime intensity penalty, with the Northern Ireland 50% deduction and the EU’s own 50% international rule preventing the same tonne being charged twice across the UK-EEA boundary. Charter parties increasingly allocate the UK ETS cost between owner and charterer the way BIMCO CII and emissions clauses allocate other regulatory exposures, since the party that controls speed and routing controls the emissions and therefore the surrender bill.

Comparison with the EU ETS for shipping

The UK and EU schemes are built to interlock at the UK-EEA boundary, but they aren’t identical. The table sets the confirmed UK domestic position against the EU regime.

The single most consequential design choice is the Northern Ireland 50% deduction read together with the EU’s 50% international rule: between them they keep a UK-to-EEA voyage charged once at full, split across the two schemes, while keeping a Belfast routing on a par with a Dublin routing into Great Britain.

Future outlook

Three things are confirmed and dated: domestic maritime entry on 1 July 2026, the 5,000 GT threshold with a 2028 review, and the double-surrender phase-in resolving at the 30 April 2028 deadline. The offshore sector joins on 1 January 2027. Everything beyond that is proposal or contingency.

The international-voyage extension is the largest open question, proposed for 1 January 2028 at 50% coverage but tied to the UK-EU linking negotiation and not yet legislated. Linking the UK and EU schemes outright, so a UKA and an EUA are mutually recognized, sits further out and depends on the same political track. The 2028 threshold review could pull more of the coastal and short-sea fleet into scope below 5,000 GT. And the CH4 and N2O pricing, already live for maritime from the domestic start, sharpens the case against unmitigated methane slip on dual-fuel ships as LNG capacity grows. The regime will sit alongside the IMO Net-Zero Framework global measures, FuelEU Maritime, and the MARPOL Annex VI air-pollution and efficiency rules as one of several overlapping carbon-price and intensity signals a UK-trading ship has to manage at once.

Why a cap adjustment, and why that exact number

The 9,323,546-allowance addition is the technical heart of the maritime decision, and it’s easy to read past it as a rounding artifact. It isn’t. A cap-and-trade scheme works because allowances are scarce; the cap sets total permitted emissions, and the price emerges from competition for a fixed pool. Drop a whole new sector into a fixed cap and one of two bad things happens. Either the new sector buys allowances the incumbents were counting on, tightening supply and pushing the price up for power, industry, and aviation without any policy intent to do so, or the Authority lets the new sector emit outside the cap, which breaks the environmental integrity the cap exists to guarantee.

The Authority chose the third path: expand the cap by the modeled net-zero-consistent volume of the incoming sector. The 9,323,546 figure is that modeled volume for domestic maritime, drawn from the Maritime Decarbonisation Strategy trajectory rather than from current emissions. That distinction matters. A cap addition set at today’s emissions would lock in current activity; a cap addition set at the net-zero path builds in the decline the sector is expected to deliver, so the maritime contribution to the cap shrinks year on year the way the headline cap does. The Authority stated the governing principle plainly: scope expansion during a trading phase has to come with a cap adjustment that preserves cap integrity. The number follows from the principle, not the other way round.

That the maritime allowances flow entirely to auction, with none diverted to a reserve, is the corollary of the no-free-allocation decision. The Authority noted that any allowances added to reserve pots would not have been accessible to a sector that receives no free allocation and buys everything it surrenders, so routing the addition to auction is the only coherent treatment. For an operator, the practical read is simple: the allowances exist, they’re for sale, and the sector competes for them at the same auctions and on the same secondary market as every other participant.

The point of obligation and per-operator reporting

One of the five changes from baseline UK MRV is alignment with the UK ETS point of obligation, and it carries more weight than its dry phrasing suggests. In a cap-and-trade scheme, the point of obligation is the legal answer to a single question: who has to surrender the allowances. For power and industry the answer is the installation operator. For maritime the Authority defined it on the operator, and combined it with per-operator rather than per-ship reporting.

That’s a real departure from the per-ship logic that runs through the EU MRV Regulation, the IMO Data Collection System, and most of the technical machinery a superintendent works with day to day. Under MRV, each ship has its own monitoring plan, its own emissions report, and its own Document of Compliance. Under UK ETS maritime, the operating company aggregates its fleet’s in-scope emissions and surrenders against the total as a single counterparty. The Authority gains a cleaner enforcement target, one company to pursue rather than a fleet of separately flagged hulls, some of which may sit in single-ship companies for liability reasons.

For the operator, aggregation cuts both ways. It simplifies the surrender into one annual transaction across the fleet, but it forces clarity on who the operator actually is for each ship, which in a time-charter or bareboat structure isn’t always the registered owner. The party that controls the commercial operation, sets the speed, and chooses the route is the party generating the emissions, and the point-of-obligation definition has to land the surrender duty on that party for the price signal to reach the decisions that move emissions. This is the same allocation problem that BIMCO CII and emissions clauses address in charter parties, and operators trading into UK domestic waters need their charter terms to track the UK ETS point of obligation, not just the EU one.

Methane and nitrous oxide: the dual-fuel cost

Bringing methane and nitrous oxide into scope from the domestic start, ahead of where retained UK MRV sat, changes the calculus for LNG-fueled ships. Retained UK MRV counted CO2 only. The UK ETS maritime obligation counts CO2 equivalent, converting CH4 at GWP 28 and N2O at GWP 265 on the 100-year basis the Authority confirmed.

For a conventional fuel-oil ship the addition is marginal; N2O from marine diesel combustion is small. For a dual-fuel ship burning LNG it can be decisive. Low-pressure dual-fuel engines let a fraction of the methane pass through unburned, the phenomenon known as methane slip, and unburned methane is a potent greenhouse gas. At GWP 28, a slip rate of a few percent of fuel mass can erode a meaningful share of the CO2 saving LNG delivers against fuel oil at the funnel. The UK ETS now prices that slip directly, so the carbon case for LNG as a marine fuel on UK domestic trade depends on the specific engine’s slip characteristics, not on the lower-carbon headline of the fuel. An operator weighing an LNG newbuild for coastal UK trade has to model the slip-adjusted CO2-equivalent emissions, not the tank-to-wake CO2 alone, to get the surrender cost right.

The same logic will sharpen as the threshold review approaches and as more dual-fuel tonnage enters the coastal fleet. Pricing CH4 and N2O from day one, rather than phasing them in, signals that the UK regime treats the slip as a cost the operator owns, not a transitional allowance.

Interaction with the IMO and EU measures

A UK-trading ship rarely faces the UK ETS alone. On a UK domestic voyage, the UK ETS is the carbon-price instrument that bites. Step into international trade and the picture layers up. The IMO Net-Zero Framework mid-term measures set a global fuel-intensity standard and a pricing element for international voyages; the EU ETS for shipping prices intra-EEA and 50% of EEA-international emissions; and FuelEU Maritime penalizes ships whose well-to-wake fuel intensity exceeds a declining limit. These are different instruments measuring different things: the UK ETS and EU ETS price absolute tonnes; FuelEU prices intensity; the IMO framework blends a standard with a charge.

The Authority committed to monitor the international schemes and to avoid double charging of the same emissions. The clearest expression of that is the UK-EEA arrangement, where the UK ETS 50% international proposal and the EU’s existing 50% international rule are designed so the two together cover 100% of a UK-EEA voyage once, each side taking half. The Northern Ireland to Great Britain 50% deduction is the domestic-side mirror of the same anti-double-charging discipline. What the schemes don’t do is net against each other across instrument types: paying a FuelEU intensity penalty doesn’t reduce a UK ETS surrender, because they price different things. An operator’s total regulatory carbon exposure on a UK-EEA container loop is the sum of the UK ETS surrender on the UK leg and in port, the EU ETS surrender on the EEA and international portions, and any FuelEU penalty on the voyage intensity, with the 50% rules preventing the absolute-tonne instruments from charging the same tonne twice.

That stack is why the operational levers matter so much. A tonne of fuel saved cuts the UK ETS surrender, the EU ETS surrender, and the FuelEU intensity at once, because all three trace back to fuel burned. The levers compound across regimes even though the regimes don’t net against each other.

Practical compliance steps for an operator

The compliance path for a ship crossing the 5,000 GT threshold on UK domestic trade has a defined order. First, confirm scope: is the ship at or above 5,000 GT, does it perform UK domestic voyages or sit at UK berths, and does any exemption apply (Scottish island or peninsula ferry, fishing, government, or the offshore timing carve-out). Second, fix the point of obligation: identify which operating company surrenders, which in a chartered structure means reading the charter party against the UK ETS operator definition. Third, get the monitoring plan approved by the regulator, the tighter gate UK ETS imposes over verifier-only assessment, and confirm it captures CH4 and N2O alongside CO2.

Then the cycle runs annually. Monitor in-scope emissions on a ship-activity basis through the scheme year. Have the annual emissions report verified and submitted by 31 March following the year. Acquire UKAs at auction or on the secondary market across the year, planning against the Auction Reserve Price floor as the known lower bound on cost. Surrender by 30 April, remembering the double-surrender concession that pushes both the 2026 half-year and the 2027 year to a single 30 April 2028 deadline. For a ship that also trades EEA, run the UK and EU obligations off the same monitoring spine and the same accredited verifier where possible, applying the Northern Ireland 50% deduction on the qualifying corridor and the EU 50% rule on EEA-international legs. The UK ETS shipping liability calculator turns the activity profile and a UKA price into the surrender total, and the EU MRV emissions calculator produces the per-voyage CO2 the surrender is built from.

Limitations

This article states the confirmed domestic-maritime policy from the UK ETS Authority’s main response and the proposed international extension from the separate live consultation. The two have different legal weight. The 1 July 2026 domestic start, the 5,000 GT threshold, the 9,323,546-allowance cap addition, the no-free-allocation decision, the Northern Ireland 50% deduction, the double-surrender deadline of 30 April 2028, and the GWP factors (CO2 = 1, CH4 = 28, N2O = 265) are confirmed Authority decisions. The 1 January 2028 international date, the 50% international coverage, and the indicative international cap figures are proposals in consultation and can change before they become law; do not plan capital commitments on them as if settled.

Figures move. The Auction Reserve Price was GBP 28 as of April 2026 and is inflation-linked from 1 January 2027, so the floor on any future date has to be read from the then-current GDP-deflator adjustment, not from this page. The UKA market price is not a policy figure at all; it’s set by the secondary market and the quarterly auctions, and the worked carbon-cost magnitudes here are illustrative, not quotes. The Cost Containment Mechanism trigger is a condition, not a price cap, so it offers no guaranteed ceiling an operator can rely on.

Scope edges need care. The exemptions for Scottish island and peninsula ferries, fishing, and government activity are defined in the Authority response by category, and a vessel’s exemption depends on the activity it performs, not only on its type. The offshore inclusion date is 1 January 2027, distinct from the 1 July 2026 general start. The per-operator reporting basis means fleet aggregation rules govern who surrenders, which can differ from the per-ship intuition carried over from MRV and the IMO DCS. For a specific vessel and trade, read the Authority response and the implementing legislation in full and confirm with the regulator before relying on a scope conclusion. This page is a reference, not regulatory advice, and the primary sources cited below govern in any conflict.

Related Calculators

• EU MRV to EU ETS Allowance Crosswalk Calculator
• EU ETS, Annual Allowance Cost Calculator
• EU MRV Emissions Report Calculator
• Norway NOx Fund Levy Calculator
• FuelEU Maritime, GHG Penalty Cost Calculator
• CARB At-Berth Compliance Calculator
• Cold Ironing / OPS Offset Calculator
• Shore Power, Required Cable Size Calculator
• GFI Attained - WtW Intensity from Fuel Mix Calculator
• GFI Compliance - IMO Net-Zero Framework Calculator
• SEEMP Combined Operational Measures Calculator
• MARPOL Annex VI/22, SEEMP Calculator
• MARPOL Annex VI/26, SEEMP revised Calculator
• CII Attained Calculator
• CII Required Calculator
• CII Rating (A–E) Calculator
• CII Corrective Trajectory Calculator
• EPL Required MCR Reduction Calculator
• EEXI Attained Calculator
• EEDI Attained Calculator
• CH₄ Methane Slip Calculator
• LNG Methane Slip, GWP20 / GWP100 GHG Calculator
• LNG, Otto MS / Otto SS / Diesel WtW Calculator
• MARPOL Annex VI, NOx Tier II Limit Calculator
• MARPOL Annex VI, NOx Tier III Limit Calculator
• NOx Tier Compliance Check Calculator
• SOₓ from Fuel Sulphur Calculator
• PM10 / PM2.5 Calculator
• Black Carbon Calculator
• ECA Fuel-Cost Premium Calculator
• ESI, Environmental Ship Index Calculator
• MARPOL Annex VI/5, Survey and certification Calculator
• MARPOL Annex VI/6, IAPP certificate Calculator
• MARPOL Annex VI/10, Port state control NOx Calculator
• IMO DCS, Annual Fuel Report Calculator
• BDN Reconciliation / ROB Check Calculator
• Cube Law Fuel Ratio Calculator
• Engine, Thermal Efficiency Calculator
• CII, SFOC & Fuel Mix Quick Check Calculator

See also

• EU ETS for shipping - the parallel and largely-aligned EU regime
• EU MRV Regulation 2015/757 - the underlying data infrastructure
• FuelEU Maritime explained - the parallel EU intensity regime
• FuelEU penalties, pooling and multipliers - FuelEU mechanics
• CARB At-Berth Regulation - the parallel California regional regime
• MARPOL Annex VI - the global air-pollution and GHG framework
• IMO Net-Zero Framework - the global GHG pricing mechanism from 2027
• IMO GHG Strategy - the IMO policy framework
• What is CII - operational carbon intensity indicator
• What is EEDI - design-phase index
• What is EEXI - existing-ship index
• SEEMP I, II and III - energy-efficiency management plan
• EEXI EPL and ShaPoLi - EEXI compliance levers
• CII Corrective Action Plan - corrective measures for D/E-rated ships
• Slow steaming and CII - operational lever
• Emission Control Areas - regional sulphur and NOx framework
• NOx Tier I, II and III - engine certification regime
• IMO 2020 sulphur cap - global sulphur cap
• Cold ironing and shore power - in-port emission reduction
• IMO DCS vs EU MRV - reporting infrastructure comparison
• Biofuels in shipping - low-carbon fuel pathway
• LNG as marine fuel - dual-fuel pathway
• Methanol as marine fuel - alternative pathway
• Ammonia as marine fuel - zero-carbon pathway
• Heavy fuel oil - residual fuel
• Marine gas oil - distillate fuel
• Specific fuel oil consumption - engine efficiency metric
• Exhaust gas cleaning system - scrubber technology
• Selective catalytic reduction - SCR for Tier III NOx
• Marine diesel engine - engine technology subject to ETS
• LNG fuel system - dual-fuel ship handling
• MARPOL Convention - parent IMO treaty
• SOLAS Convention - principal IMO safety treaty
• STCW Convention - training and watchkeeping standards
• COLREGs Convention - parallel IMO instrument
• Port state control - parallel federal enforcement framework (MCA in UK)
• Classification society - dual role as MRV verifiers
• Flag state and flag of convenience - flag-state role
• EU MRV emissions calculator - per-voyage emissions calculation
• EU MRV to EU ETS allowance crosswalk calculator - bridges MRV data to ETS surrender (UK ETS uses same arithmetic)
• MARPOL EU ETS cost calculator - EU ETS surrender cost
• MARPOL FuelEU penalty calculator - FuelEU non-compliance penalty
• CARB at-berth compliance calculator - California compliance check
• Cold ironing OPS offset calculator - per-visit emissions reduction
• Shore power required cable size calculator - cable sizing
• HVSC 6.6 / 11 kV system calculator - high-voltage connection design
• GFI attained calculator - WtW intensity from fuel mix
• GFI compliance calculator - Net-Zero Framework compliance position
• SEEMP combined operational measures calculator - non-overlapping savings stack
• SEEMP Part I calculator - Part I structure
• SEEMP Part III calculator - Part III CII operational plan
• CII attained calculator - operational CII calculation
• CII required calculator - regulation-driven Required CII
• CII rating calculator - A-to-E rating mapping
• CII corrective trajectory calculator - corrective plan forecast
• EPL required MCR reduction calculator - EEXI compliance limited MCR
• EEXI attained calculator - EEXI as-built calculation
• EEDI attained calculator - design-phase index calculation
• Methane slip calculator - LNG dual-fuel methane slip
• Methane slip CO₂-equivalent calculator - GWP100 conversion
• LNG well-to-wake calculator - LNG WtW intensity
• Tier II NOx calculator - rated-speed-dependent Tier II
• Tier III NOx calculator - rated-speed-dependent Tier III
• NOx Tier compliance check calculator - integrated tier compliance check
• SOx from fuel sulphur calculator - SOx mass-emission rate
• PM10 / PM2.5 calculator - particulate matter emission estimate
• Black carbon calculator - IMO Black Carbon Reference Method
• Norway NOx Fund calculator - national NOx levy
• ECA fuel-cost premium calculator - trade-route ECA economics
• ESI score calculator - Environmental Ship Index voluntary recognition
• Survey calculator - Annex VI survey cycle
• IAPP certificate calculator - IAPP issue and endorsement
• PSC NOx calculator - port state control inspection targeting
• IMO DCS report calculator - annual fuel-consumption report
• BDN reconciliation calculator - on-board fuel reconciliation
• Engine cube-law fuel calculator - speed-fuel relationship
• Brake thermal efficiency calculator - engine thermal efficiency
• SFOC-to-CII converter - engine SFOC to ship CII rating
• ShipCalculators.com calculator catalogue - full listing

Additional calculators:

• UK ETS Shipping UKA Liability Calculator
• EU ETS - Allowance Surrender Schedule

Additional related wiki articles:

• EUA Market Mechanics for Shipping
• BIMCO CII and Emissions Clauses

References

1. UK ETS Authority. UK ETS scope expansion: domestic maritime, main Authority response. GOV.UK.
2. UK ETS Authority. UK Emissions Trading Scheme scope expansion: maritime (consultation). GOV.UK.
3. UK ETS Authority. UK Emissions Trading Scheme (UK ETS): a policy overview. GOV.UK.
4. UK ETS Authority. UK ETS scope expansion: emissions from international maritime voyages (consultation). GOV.UK.
5. UK Government. Greenhouse Gas Emissions Trading Scheme Order 2020 (SI 2020/1265), operative 1 January 2021.
6. Department for Transport. Maritime Decarbonisation Strategy. GOV.UK.