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 |
|---|---|---|---|---|---|
| 1001 |
HOUYOSHI PARK
IMO 9725847
|
19,998 | 2016 |
10.7
|
D |
| 1002 |
TERN OCEAN
IMO 9747986
|
14,827 | 2017 |
10.7
|
D |
| 1003 |
ACADIAN
IMO 9298715
|
37,515 | 2005 |
10.7
|
D |
| 1004 |
SEYCHELLES PIONEER
IMO 9255517
|
37,500 | 2005 |
10.7
|
D |
| 1005 |
SCARLET RAY
IMO 9799654
|
19,974 | 2020 |
10.7
|
D |
| 1006 |
TEAL RAY
IMO 9838668
|
19,999 | 2019 |
10.7
|
D |
| 1007 |
BOW TIGER
IMO 9989223
|
25,917 | 2024 |
10.7
|
D |
| 1008 |
ORIENTAL TULIP
IMO 9890549
|
16,268 | 2020 |
10.7
|
D |
| 1009 |
CHEM TAURUS
IMO 9477505
|
19,960 | 2010 |
10.8
|
D |
| 1010 |
MTM VANCOUVER
IMO 9867607
|
22,344 | 2019 |
10.8
|
D |
| 1011 |
SWAN PACIFIC
IMO 9749805
|
19,997 | 2016 |
10.8
|
D |
| 1012 |
SAPPHIRE
IMO 9443425
|
37,593 | 2009 |
10.8
|
D |
| 1013 |
GINOSTRA M
IMO 1021673
|
18,639 | 2024 |
10.8
|
D |
| 1014 |
CHEMICAL ENTERPRISE
IMO 9827475
|
15,945 | 2018 |
10.8
|
D |
| 1015 |
STOLT SPRAY
IMO 9168611
|
22,201 | 2000 |
10.8
|
D |
| 1016 |
FINNSTRAUM
IMO 9172222
|
16,028 | 1999 |
10.8
|
D |
| 1017 |
NISEKO GALAXY
IMO 9804930
|
25,183 | 2020 |
10.9
|
D |
| 1018 |
CAPTAIN M. KYRIAKOU
IMO 1025411
|
18,330 | 2025 |
10.9
|
D |
| 1019 |
CHEM COBALT
IMO 9740770
|
19,990 | 2016 |
10.9
|
D |
| 1020 |
MAC TOKYO
IMO 9343778
|
19,998 | 2006 |
10.9
|
D |
| 1021 |
STOLT ACHIEVEMENT
IMO 9124469
|
37,141 | 1999 |
10.9
|
D |
| 1022 |
GINGA LYNX
IMO 9442550
|
25,900 | 2009 |
10.9
|
D |
| 1023 |
KITIKMEOT W.
IMO 9421219
|
19,983 | 2010 |
10.9
|
D |
| 1024 |
MAREX NINA
IMO 1027897
|
12,263 | 2025 |
10.9
|
D |
| 1025 |
MINERVA LEO
IMO 9723289
|
39,070 | 2015 |
10.9
|
D |
| 1026 |
VARI TRADER
IMO 9800025
|
19,803 | 2018 |
10.9
|
D |
| 1027 |
CHEM NEW ORLEANS
IMO 9705756
|
19,995 | 2015 |
11.0
|
D |
| 1028 |
STOLT INVENTION
IMO 9102100
|
36,733 | 1997 |
11.0
|
D |
| 1029 |
AMELIA
IMO 9624768
|
21,203 | 2011 |
11.0
|
D |
| 1030 |
SWAN ATLANTIC
IMO 9790464
|
19,998 | 2017 |
11.0
|
D |
| 1031 |
REBECCA SCHULTE
IMO 9576753
|
25,620 | 2011 |
11.0
|
D |
| 1032 |
CHEM SIRIUS
IMO 9558397
|
19,986 | 2011 |
11.0
|
D |
| 1033 |
CHEMICAL HUNTER
IMO 9758789
|
16,081 | 2015 |
11.0
|
D |
| 1034 |
GAIA DESGAGNES
IMO 9739800
|
17,999 | 2018 |
11.1
|
D |
| 1035 |
ATA VOYAGER
IMO 9408360
|
9,531 | 2009 |
11.1
|
D |
| 1036 |
NYMPH THETIS
IMO 9232369
|
17,427 | 2000 |
11.1
|
D |
| 1037 |
GULF PETROLEUM 4
IMO 9439345
|
13,006 | 2009 |
11.1
|
D |
| 1038 |
SHAMROCK JUPITER
IMO 9416082
|
19,837 | 2009 |
11.1
|
D |
| 1039 |
SONGA EAGLE
IMO 9388704
|
25,421 | 2008 |
11.2
|
D |
| 1040 |
CITY ISLAND
IMO 9360960
|
19,996 | 2007 |
11.2
|
D |
| 1041 |
GINGA COUGAR
IMO 9321861
|
26,180 | 2005 |
11.2
|
D |
| 1042 |
EASLINE GUANGZHOU
IMO 9249594
|
19,924 | 2001 |
11.2
|
D |
| 1043 |
EVA HANSA
IMO 9985980
|
19,944 | 2023 |
11.2
|
D |
| 1044 |
ORIS HELGA
IMO 9483619
|
7,739 | 2008 |
11.2
|
D |
| 1045 |
SAPPHIRE A
IMO 9407081
|
19,701 | 2008 |
11.2
|
D |
| 1046 |
LILA EVIA
IMO 9330771
|
19,959 | 2006 |
11.3
|
D |
| 1047 |
MED PACIFIC
IMO 9461934
|
26,234 | 2012 |
11.3
|
D |
| 1048 |
GULHOLMEN
IMO 9435703
|
16,817 | 2009 |
11.3
|
D |
| 1049 |
MELATI 7
IMO 9172272
|
31,960 | 2000 |
11.3
|
D |
| 1050 |
NO.5 OCEAN PIONEER
IMO 9409510
|
19,993 | 2009 |
11.3
|
D |
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.