Oil tanker · Denmark flag · built 2017
BRITISH CENTURY: CO₂ emissions 2018–2025
IMO 9682978 EU ETS6 reporting years
- CO₂ reported 2025
- 26,925 t
- Fuel burned
- 8,544 t
- Distance
- 58,249 nm
- Time at sea
- 4,909 h
- Emitted at berth
- 8% of total
- Share of year under way
- 56%
- Gross tonnage
- 85,445
BRITISH CENTURY against its type
Built in 2017, it is 7 years newer than the median oil tanker on this register, which was built in 2010 (2,896 vessels with a known build year). At 85,445 gross tonnage it is larger than 85% of the other 2,841 oil tankers with a recorded tonnage. It is one of 72 oil tankers here under the Denmark flag, 2.0% of the 3,548 on the register. Its MRV returns name it BRITISH CENTURY for 2018 and EFFIE MAERSK for 2020–2025. The reported port of registry changed: Douglas (2018), then Svendborg (2020–2025).
Its 26,925 t of CO₂ for 2025 is 3.4 times the median of 7,922 t among the 1,704 oil tankers on this register that reported for 2025. Per nautical mile it emitted 462.2 kg CO₂, 15% above the type median of 403.2 kg. It logged 4,909 hours at sea against a median of 2,030 hours for its type that year. 7.7% of its 2025 emissions were at berth; the median for oil tankers was 7.8%. Across 6 years with reported emissions, the highest was 2025 (26,925 t) and the lowest 2023 (645 t). Its efficiency percentile within the type went from 36 in 2018 to 15 in 2025 (lower is more efficient). Of the 5 comparable vessels listed below with a 2025 return, 2 reported a lower CO₂ per nautical mile than this vessel.
Emissions by year2018–2025
| Year | CO₂ (t) | Fuel (t) | Distance (nm) | At sea (h) | At berth (t) | kg CO₂/nm | EEOI | Percentile |
|---|---|---|---|---|---|---|---|---|
| 2025 | 26,925 | 8,544 | 58,249 | 4,909 | 2,086 | 462.2 | 4.8 | 15 |
| 2023 | 645 | 204 | — | 137 | 287 | 505.6 | — | — |
| 2022 | 16,987 | 5,429 | 39,582 | 3,307 | 1,399 | 429.2 | 6.3 | 29 |
| 2021 | 7,874 | 2,520 | 17,636 | 1,411 | 302 | 446.5 | 5.3 | 17 |
| 2020 | 8,028 | 2,561 | 15,890 | 1,399 | 1,017 | 505.2 | 15.3 | 81 |
| 2018 | 9,918 | 3,176 | 20,337 | 2,066 | 680 | 487.7 | 7.1 | 36 |
Vessel particulars
- IMO number
- 9682978
- Previously reported as
- EFFIE MAERSK
- Ship type
- Oil tanker
- Gross tonnage
- 85,445
- Length overall
- 274.0 m
- Beam
- 49.0 m
- Year built
- 2017
- Flag state
- Denmark per EU MRV 2025
Sources disagree: Wikidata/AIS (undated) list United Kingdom. The flag shown is from the newest official source, the EU MRV return for 2025. - Port of registry
- Svendborg MRV 2025
- Technical efficiency (design)
- EEDI (2.69 gCO₂/t·nm)
- Verifier
- AMERICAN BUREAU OF SHIPPING HELLENIC SINGLE MEMBER LIMITED LIABILITY COMPANY (ABS HELLENIC S.M. LTD), Greece
- Accreditation
- 1083-2
- Compliance document issued
- 2026-03-26
- Compliance document expires
- 2027-06-30
Efficiency against its own type2025
Position 220 of 1,448 qualifying oil tankers by EEOI, at the 15th percentile. The dashed line is the type median, 7.5; this vessel reported 4.8.
EEOI divides emissions by transport work, which for this vessel and year was 5,586,062,241 tonne-miles over 58,249 nautical miles.
Reported CO₂ by year
Reported CO₂ in 2025 was 171.5% higher than in 2018, for EU/EEA voyages only. No return is recorded for 2019, 2024, so the series has gaps.
From 2023 to 2025, emissions rose 4,077.2% and CO₂ per nautical mile fell 8.6%.Distance is missing for at least one of the two years, so activity and efficiency cannot be separated here.
Where the 2025 emissions occurred
Methane, nitrous oxide and EU ETS2025
- Total CO₂ equivalent
- 27,344 t
- Methane (CH₄)
- 0.43 t
- Nitrous oxide (N₂O)
- 1.54 t
- Under EU ETS
- 19,192 t, 71% of total
Laden voyages2025
- CO₂ on laden voyages
- 16,366 t, 61% of total
- Fuel, laden
- 5,199 t
- CO₂ per nm, laden
- 424.8 kg
The rest of the 2025 total was emitted on ballast legs or at berth.
Sources and how to read this
- Emissions: EU MRV publication (THETIS-MRV), reporting years 2018–2025, published by the European Commission.
- Vessel particulars: Wikidata (CC0).
This page draws on 6 MRV reporting years, an efficiency ranking, 4 of 5 vessel particulars and a name history. Not found in the sources for this vessel: AIS movements in Norwegian waters, a licensed photograph, a sanctions listing and US port state inspections.
Empty means unreported, never zero. How EEOI, distance, percentiles and sister ships are handled is explained under reading a vessel page. Something wrong? See corrections.