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 |
|---|---|---|---|---|---|
| 52 |
CREOLE SUN
IMO 9850214
|
49,760 | 2019 |
4.5
|
A |
| 51 |
TORM DANICA
IMO 9702194
|
50,000 | 2015 |
4.5
|
A |
| 53 |
DINO
IMO 9995454
|
50,479 | 2025 |
4.5
|
A |
| 54 |
MONA
IMO 9917880
|
55,202 | 2022 |
4.5
|
A |
| 55 |
ST. PETRI
IMO 9788497
|
50,105 | 2019 |
4.5
|
A |
| 56 |
KK MARLIN
IMO 9835939
|
77,452 | 2021 |
4.6
|
A |
| 58 |
STENA PROMISE
IMO 9923748
|
49,990 | 2022 |
4.6
|
A |
| 60 |
JEFFREYS BAY
IMO 1013937
|
49,999 | 2025 |
4.6
|
A |
| 57 |
TORM BELIS
IMO 9661247
|
49,995 | 2012 |
4.6
|
A |
| 59 |
MARIA
IMO 9917828
|
55,202 | 2022 |
4.6
|
A |
| 63 |
TORM SPLENDID
IMO 9854791
|
49,932 | 2020 |
4.6
|
A |
| 62 |
ATHENS C
IMO 1019761
|
50,170 | 2025 |
4.6
|
A |
| 61 |
TORM STRENGTH
IMO 9836036
|
49,999 | 2019 |
4.6
|
A |
| 64 |
TORM INNOVATION
IMO 9602722
|
73,847 | 2013 |
4.6
|
A |
| 65 |
CAPTAIN LEON
IMO 9831206
|
49,999 | 2018 |
4.6
|
A |
| 66 |
NORD MINAMI
IMO 9883041
|
52,825 | 2020 |
4.6
|
A |
| 67 |
TORM DIWATA
IMO 9683350
|
49,680 | 2014 |
4.7
|
A |
| 68 |
TORM SUCCESS
IMO 9836048
|
49,976 | 2019 |
4.7
|
A |
| 70 |
ARDMORE DAUNTLESS
IMO 9707388
|
37,764 | 2015 |
4.7
|
A |
| 69 |
PS NEW ORLEANS
IMO 9919577
|
52,853 | 2022 |
4.7
|
A |
| 71 |
MANCHAC SUN
IMO 9724013
|
49,994 | 2016 |
4.7
|
A |
| 72 |
STAMATIA
IMO 9864332
|
49,999 | 2019 |
4.7
|
A |
| 73 |
CHIOS STAR
IMO 9827566
|
50,506 | 2018 |
4.7
|
A |
| 75 |
TORM DENISE
IMO 9702211
|
49,999 | 2015 |
4.7
|
A |
| 74 |
SILVER ELEANOR
IMO 9692301
|
49,746 | 2015 |
4.7
|
A |
| 76 |
SOLAR TINE
IMO 9898527
|
49,343 | 2021 |
4.7
|
A |
| 78 |
TABLE BAY
IMO 9974979
|
50,000 | 2024 |
4.7
|
A |
| 77 |
FARIDA
IMO 9845099
|
55,604 | 2020 |
4.7
|
A |
| 79 |
GOLDEN SUN
IMO 1018860
|
49,988 | 2024 |
4.7
|
A |
| 80 |
YASA SEAGULL
IMO 9619543
|
49,990 | 2017 |
4.8
|
A |
| 81 |
CAPE TEMPEST
IMO 9407263
|
73,720 | 2008 |
4.8
|
A |
| 82 |
PACIFIC AQUAMARINE
IMO 9994515
|
49,820 | 2025 |
4.8
|
A |
| 84 |
ATLANTIC MARBLE
IMO 9798959
|
49,999 | 2018 |
4.8
|
A |
| 83 |
BOXER
IMO 9814193
|
49,852 | 2019 |
4.8
|
A |
| 85 |
CELSIUS PORTSMOUTH
IMO 9884837
|
50,299 | 2021 |
4.8
|
A |
| 86 |
SAVONETTA SUN
IMO 9911549
|
49,999 | 2022 |
4.8
|
A |
| 88 |
LARGO CALIFORNIA
IMO 9843780
|
50,290 | 2019 |
4.8
|
A |
| 87 |
ARDMORE SEAFOX
IMO 9708215
|
49,999 | 2015 |
4.8
|
A |
| 89 |
DORIC COURAGE
IMO 9847451
|
49,910 | 2019 |
4.8
|
A |
| 90 |
PRECIOUS BALBOA
IMO 9997244
|
49,948 | 2025 |
4.8
|
A |
| 91 |
MARATHO
IMO 9979448
|
49,999 | 2025 |
4.9
|
A |
| 92 |
TAKAROA SUN
IMO 9850202
|
49,849 | 2019 |
4.9
|
A |
| 95 |
FPMC 34
IMO 9845166
|
49,781 | 2019 |
4.9
|
A |
| 94 |
SEAWAYS CREST
IMO 9387920
|
51,510 | 2009 |
4.9
|
A |
| 93 |
SEAEXPLORER
IMO 1014022
|
49,990 | 2025 |
4.9
|
A |
| 96 |
JAL DHVANI
IMO 1021180
|
50,667 | 2025 |
4.9
|
A |
| 98 |
ELANDRA REDWOOD
IMO 9834337
|
49,999 | 2018 |
4.9
|
A |
| 97 |
RENAD
IMO 9917816
|
55,202 | 2022 |
4.9
|
A |
| 99 |
TORM SOLUTION
IMO 9836050
|
49,999 | 2019 |
4.9
|
A |
| 100 |
SM OSPREY
IMO 9786231
|
50,034 | 2017 |
4.9
|
A |
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.