Most Emission-Efficient Oil Tankers
Ships ranked by AER (Annual Efficiency Ratio) — grams of CO₂ emitted per tonne of deadweight carried one nautical mile (g CO₂/dwt·nm), the IMO carbon-intensity metric behind the CII rating — from official EU MRV emissions data for reporting year 2024. Lower is greener. Pick a segment and size class to see the greenest vessels first.
| # | Vessel | Size (DWT) | Built | Carbon intensity — AER (g CO₂/dwt·nm) | Grade |
|---|---|---|---|---|---|
| 351 |
FREUD
IMO 9804461
|
157,620 | 2018 |
2.9
|
A |
| 350 |
MOSCOW SPIRIT
IMO 9418602
|
156,480 | 2010 |
2.9
|
A |
| 356 |
MARAN HERMIONE
IMO 9779379
|
157,755 | 2017 |
2.9
|
A |
| 355 |
FRONT SPARTA
IMO 9847114
|
158,006 | 2019 |
2.9
|
A |
| 357 |
DELTA HELLAS
IMO 9406673
|
157,583 | 2009 |
2.9
|
A |
| 354 |
TORM MATHILDE
IMO 9358412
|
109,672 | 2008 |
2.9
|
A |
| 353 |
SUNRISEWAY
IMO 9907665
|
158,307 | 2022 |
2.9
|
A |
| 359 |
MONTE SERANTES
IMO 9841615
|
156,584 | 2019 |
2.9
|
A |
| 358 |
DILIGENT WARRIOR
IMO 9750050
|
159,000 | 2016 |
2.9
|
A |
| 360 |
MARAN HOMER
IMO 9761372
|
156,458 | 2017 |
2.9
|
A |
| 362 |
MONTESTENA
IMO 9585883
|
159,372 | 2012 |
2.9
|
B |
| 361 |
ACHILLEAS
IMO 9398072
|
297,863 | 2010 |
2.9
|
B |
| 363 |
THOMAS ZAFIRAS
IMO 9724087
|
113,691 | 2016 |
2.9
|
B |
| 365 |
MONTREAL SPIRIT
IMO 9296389
|
149,997 | 2006 |
2.9
|
B |
| 364 |
TORM HERMIA
IMO 9797993
|
114,939 | 2018 |
2.9
|
B |
| 366 |
SEABLISS
IMO 9587207
|
158,982 | 2012 |
2.9
|
B |
| 368 |
FRONT ULL
IMO 9600932
|
157,000 | 2014 |
2.9
|
B |
| 367 |
AFRICA
IMO 9905320
|
163,220 | 2022 |
2.9
|
B |
| 370 |
OTTOMAN NOBILITY
IMO 9290359
|
152,622 | 2005 |
2.9
|
B |
| 369 |
SEAWAYS BRAZOS
IMO 9594731
|
158,537 | 2012 |
2.9
|
B |
| 371 |
SHENLONG SPIRIT
IMO 9379210
|
159,021 | 2009 |
2.9
|
B |
| 373 |
ITHAKI DF
IMO 9953494
|
114,598 | 2024 |
2.9
|
B |
| 372 |
AFRODITI
IMO 9452880
|
166,164 | 2011 |
2.9
|
B |
| 374 |
DELTA KANARIS
IMO 9429015
|
157,563 | 2010 |
2.9
|
B |
| 376 |
DELTA MED
IMO 9412309
|
161,653 | 2010 |
2.9
|
B |
| 375 |
SABRINA GLORY
IMO 9959929
|
115,397 | 2024 |
2.9
|
B |
| 382 |
SEAVIOLET
IMO 9790983
|
158,480 | 2015 |
3.0
|
B |
| 381 |
OTTOMAN EQUITY
IMO 9404950
|
150,545 | 2008 |
3.0
|
B |
| 380 |
DESIMI
IMO 9395305
|
296,865 | 2011 |
3.0
|
B |
| 379 |
SEAWAYS PECOS
IMO 9594743
|
158,464 | 2012 |
3.0
|
B |
| 378 |
KRITI FUTURE
IMO 9924326
|
156,734 | 2022 |
3.0
|
B |
| 377 |
DELTA HARMONY
IMO 9408463
|
157,410 | 2009 |
3.0
|
B |
| 385 |
BOUVARDIA
IMO 9935595
|
111,009 | 2022 |
3.0
|
B |
| 384 |
SEAWAYS COLORADO
IMO 9594767
|
158,614 | 2010 |
3.0
|
B |
| 383 |
LR2 OLIVIA
IMO 9740469
|
109,985 | 2017 |
3.0
|
B |
| 389 |
CHRISTINA
IMO 9772125
|
158,902 | 2016 |
3.0
|
B |
| 388 |
PROSTAR
IMO 9833723
|
115,643 | 2019 |
3.0
|
B |
| 387 |
SIREN
IMO 9405423
|
158,583 | 2009 |
3.0
|
B |
| 386 |
MARLIN LAGOS
IMO 9823584
|
114,853 | 2022 |
3.0
|
B |
| 393 |
BORDEIRA
IMO 9529499
|
158,513 | 2013 |
3.0
|
B |
| 392 |
SEAWAYS RIO GRANDE
IMO 9593438
|
159,056 | 2010 |
3.0
|
B |
| 394 |
AL BATEEN
IMO 9828376
|
114,637 | 2020 |
3.0
|
B |
| 391 |
DIMITRIOS
IMO 9900007
|
159,159 | 2021 |
3.0
|
B |
| 390 |
ASPEN SPIRIT
IMO 9427627
|
156,813 | 2006 |
3.0
|
B |
| 398 |
OCEAN BLUE
IMO 9955997
|
113,385 | 2021 |
3.0
|
B |
| 399 |
SAPPHIRA
IMO 9336983
|
149,876 | 2008 |
3.0
|
B |
| 397 |
KASOS
IMO 9800257
|
156,989 | 2018 |
3.0
|
B |
| 396 |
SEAHORSE 1
IMO 9956006
|
113,385 | 2024 |
3.0
|
B |
| 395 |
SONANGOL HUILA
IMO 9575565
|
157,871 | 2012 |
3.0
|
B |
| 400 |
BUKHA
IMO 9500936
|
319,439 | 2012 |
3.0
|
B |
Which engines power the greenest fleets?
The main engine is the single largest CO₂ source on board — typically well over 80% of a ship's emissions come from propulsion. We aggregated this ranking the other way around: every engine design is scored by the measured carbon intensity of the vessels carrying it, licensee-built units merged under their design brand. The verdict from the 2024 data — modern dual-fuel designs like MAN B&W's ME-GI and WinGD's X-DF families, together with EGR/SCR-abated and ultra-long-stroke G-type engines, consistently power the most emission-friendly ships in service.
AER (Annual Efficiency Ratio) = annual CO₂ emissions ÷ (deadweight × distance sailed), the IMO carbon-intensity metric used for CII ratings. It is built only from measured CO₂, distance and deadweight — not the self-reported cargo transport-work figure, which is unreliable. Implausible outliers (top 2% per segment) are excluded. Grade A–E reflects each vessel's rank within its segment. Source: EMSA THETIS-MRV.