Most Emission-Efficient Chemical 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 2025. 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 |
|---|---|---|---|---|---|
| 450 |
ZEFYROS
IMO 9515917
|
50,155 | 2013 |
6.5
|
B |
| 452 |
TURKELI
IMO 9396749
|
50,696 | 2008 |
6.5
|
B |
| 453 |
STOLT ALM
IMO 9719238
|
32,834 | 2016 |
6.6
|
B |
| 454 |
NAVIG8 ESTELLE
IMO 9973925
|
49,155 | 2024 |
6.6
|
B |
| 455 |
MAYARO
IMO 9733703
|
30,940 | 2015 |
6.6
|
B |
| 457 |
CHAMPION EBONY
IMO 9290608
|
46,938 | 2004 |
6.6
|
B |
| 456 |
CONCERTO
IMO 9743837
|
37,350 | 2017 |
6.6
|
B |
| 458 |
CB PACIFIC
IMO 9851725
|
37,787 | 2020 |
6.6
|
B |
| 459 |
KRITI CORAL
IMO 9417220
|
49,499 | 2006 |
6.6
|
B |
| 460 |
FANFARE
IMO 9760562
|
37,256 | 2018 |
6.6
|
B |
| 461 |
BUCCOO REEF
IMO 9733674
|
30,723 | 2015 |
6.6
|
B |
| 462 |
CL AGATHA CHRISTIE
IMO 9943346
|
49,327 | 2023 |
6.6
|
B |
| 463 |
CS ANTHEM
IMO 9785691
|
49,990 | 2017 |
6.6
|
B |
| 464 |
KOKOLIGHT
IMO 9724697
|
45,999 | 2017 |
6.6
|
B |
| 467 |
ANDREA VICTORY
IMO 9288849
|
47,210 | 2005 |
6.6
|
B |
| 466 |
POLARIS
IMO 9682459
|
49,126 | 2014 |
6.6
|
B |
| 465 |
HAFNIA BERING
IMO 9725603
|
39,067 | 2015 |
6.6
|
B |
| 468 |
BOW PERSISTENT
IMO 9866782
|
36,225 | 2020 |
6.7
|
B |
| 470 |
HAFNIA MAGELLAN
IMO 9725615
|
39,067 | 2015 |
6.7
|
B |
| 469 |
VELA
IMO 9682461
|
49,126 | 2014 |
6.7
|
B |
| 472 |
PANTHERLIGHT
IMO 9724673
|
45,999 | 2016 |
6.7
|
B |
| 471 |
AQUILA
IMO 9692258
|
49,075 | 2015 |
6.7
|
B |
| 473 |
BOW SAGA
IMO 9215309
|
49,559 | 2007 |
6.7
|
B |
| 476 |
SC DRACO
IMO 9752022
|
40,924 | 2016 |
6.7
|
B |
| 475 |
SC MERCURY
IMO 9746188
|
33,985 | 2016 |
6.7
|
B |
| 474 |
BOW SUMMER
IMO 9215270
|
49,592 | 2005 |
6.7
|
B |
| 477 |
STAR OSPREY
IMO 9315068
|
51,213 | 2007 |
6.7
|
B |
| 478 |
MTM NEW ORLEANS
IMO 9749398
|
35,980 | 2016 |
6.7
|
B |
| 480 |
DIANELLA
IMO 9901087
|
49,799 | 2019 |
6.7
|
B |
| 479 |
SINO WISDOM
IMO 9375317
|
46,176 | 2006 |
6.7
|
B |
| 481 |
CHEMROAD ZENITH
IMO 9926300
|
35,777 | 2022 |
6.7
|
B |
| 483 |
VALLE LUNA
IMO 9635755
|
49,999 | 2013 |
6.7
|
B |
| 482 |
CHEM SAIPH
IMO 9731781
|
37,596 | 2017 |
6.7
|
B |
| 484 |
CHAMPION POLAR
IMO 9315939
|
47,834 | 2007 |
6.7
|
B |
| 485 |
JAZZ
IMO 9804849
|
37,361 | 2019 |
6.7
|
B |
| 486 |
IONIAN NAVIGATOR
IMO 9422237
|
46,625 | 2006 |
6.8
|
B |
| 488 |
HAFNIA LIBRA
IMO 9617959
|
52,385 | 2013 |
6.8
|
B |
| 487 |
HIGH LOYALTY
IMO 9681857
|
49,990 | 2015 |
6.8
|
B |
| 489 |
AQUARIUS T
IMO 9494668
|
46,147 | 2010 |
6.8
|
B |
| 490 |
FINNANGER
IMO 9387712
|
46,251 | 2009 |
6.8
|
B |
| 491 |
DORADO
IMO 9801574
|
50,067 | 2021 |
6.8
|
B |
| 492 |
VERIGE
IMO 9401128
|
52,725 | 2010 |
6.8
|
B |
| 493 |
PACIFIC ADVENTURE
IMO 9326938
|
46,043 | 2008 |
6.8
|
B |
| 494 |
ARDMORE SEAVANGUARD
IMO 9637088
|
51,800 | 2014 |
6.8
|
B |
| 495 |
TORM NEW ZEALAND
IMO 9443152
|
49,999 | 2011 |
6.8
|
B |
| 496 |
LIBERA
IMO 9293973
|
40,102 | 2006 |
6.8
|
B |
| 498 |
GULF HUWAYLAT
IMO 9359870
|
45,967 | 2008 |
6.9
|
B |
| 497 |
SEA CAELUM
IMO 9724582
|
45,999 | 2016 |
6.9
|
B |
| 499 |
CHEMROAD HAYA
IMO 9303649
|
33,916 | 2004 |
6.9
|
B |
| 500 |
LADY MARIELLA
IMO 9644433
|
39,316 | 2013 |
6.9
|
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 2025 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.