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 |
|---|---|---|---|---|---|
| 202 |
SILVER ORLA
IMO 9682332
|
49,746 | 2014 |
5.4
|
A |
| 201 |
BOUGAINVILLE
IMO 9581693
|
50,626 | 2013 |
5.4
|
A |
| 200 |
EGRET
IMO 9747120
|
49,996 | 2018 |
5.4
|
A |
| 204 |
ST NICHOLAS
IMO 9934149
|
50,226 | 2022 |
5.4
|
A |
| 205 |
TORM INDIA
IMO 9440033
|
46,838 | 2010 |
5.4
|
A |
| 206 |
EUROTRADER
IMO 9895927
|
49,999 | 2021 |
5.4
|
A |
| 207 |
HAFNIA PIONEER
IMO 9595632
|
74,999 | 2013 |
5.4
|
A |
| 209 |
HIGH FIDELITY
IMO 9689146
|
49,990 | 2014 |
5.4
|
A |
| 208 |
NAVIG8 GAUNTLET
IMO 9853228
|
49,768 | 2019 |
5.4
|
A |
| 210 |
NORD MIYAKO
IMO 9890927
|
52,816 | 2021 |
5.4
|
A |
| 212 |
DALMACIJA
IMO 9528134
|
49,991 | 2015 |
5.4
|
A |
| 211 |
SINO FAITH
IMO 9375575
|
53,143 | 2008 |
5.4
|
A |
| 214 |
STI MIRACLE
IMO 9833591
|
49,999 | 2020 |
5.4
|
A |
| 216 |
CAPE ANDIAMO
IMO 9995428
|
50,502 | 2024 |
5.4
|
A |
| 213 |
VENUS 9
IMO 1044663
|
49,330 | 2025 |
5.4
|
A |
| 218 |
CASTARA
IMO 9834155
|
50,620 | 2019 |
5.4
|
A |
| 217 |
CAPTAIN NIKOS
IMO 9828144
|
49,999 | 2018 |
5.4
|
A |
| 215 |
CAPE TAMPA
IMO 9441166
|
73,719 | 2009 |
5.4
|
A |
| 221 |
SEAWAYS OLIVE
IMO 9354909
|
49,999 | 2008 |
5.4
|
A |
| 220 |
TORM STELLAR
IMO 9854806
|
49,954 | 2020 |
5.4
|
A |
| 219 |
BEAGLE
IMO 9814181
|
49,850 | 2019 |
5.4
|
A |
| 222 |
STENA PROVIDENT
IMO 9944637
|
49,990 | 2023 |
5.5
|
A |
| 223 |
WISCO ADVENTURE
IMO 9858852
|
49,949 | 2021 |
5.5
|
A |
| 226 |
T JUNGFRAU
IMO 9389289
|
52,610 | 2009 |
5.5
|
A |
| 225 |
ELANDRA PALM
IMO 9746267
|
49,990 | 2016 |
5.5
|
A |
| 224 |
TORM LAURA
IMO 9375616
|
53,160 | 2008 |
5.5
|
A |
| 227 |
NAVIG8 GUIDE
IMO 9833682
|
49,761 | 2019 |
5.5
|
A |
| 228 |
ATLANTIC GUARD
IMO 9789269
|
49,951 | 2019 |
5.5
|
A |
| 229 |
MADELYN GRACE
IMO 9710488
|
50,137 | 2016 |
5.5
|
A |
| 230 |
ODYSSEAN
IMO 9854727
|
47,499 | 2018 |
5.5
|
A |
| 232 |
REDAMANCY
IMO 9939620
|
49,999 | 2025 |
5.5
|
A |
| 234 |
KARDIANI
IMO 9366263
|
51,527 | 2005 |
5.5
|
A |
| 231 |
HAKATA PRINCESS
IMO 9788564
|
49,842 | 2018 |
5.5
|
A |
| 233 |
ARDMORE ENDEAVOUR
IMO 9667942
|
49,859 | 2013 |
5.5
|
A |
| 236 |
TORM ARAWA
IMO 9543548
|
49,998 | 2012 |
5.5
|
A |
| 235 |
HIGH ADVENTURER
IMO 9788435
|
49,997 | 2017 |
5.5
|
A |
| 238 |
TORM DAGNY
IMO 9692337
|
49,635 | 2015 |
5.5
|
A |
| 237 |
SEADRIVE
IMO 9934137
|
50,394 | 2021 |
5.5
|
A |
| 239 |
ARDMORE ENGINEER
IMO 9654787
|
49,420 | 2014 |
5.5
|
A |
| 241 |
SEAWAYS GRACE
IMO 9337511
|
49,999 | 2008 |
5.5
|
A |
| 240 |
ATLANTIC JOURNEY
IMO 9798935
|
49,999 | 2018 |
5.5
|
A |
| 244 |
BOW TRIUMPH
IMO 9669902
|
49,622 | 2015 |
5.5
|
A |
| 243 |
BOW TRIBUTE
IMO 9669885
|
49,622 | 2014 |
5.5
|
A |
| 242 |
TORM CAVATINA
IMO 9343209
|
46,070 | 2010 |
5.5
|
A |
| 246 |
SEAWAYS WAVE
IMO 9387918
|
51,549 | 2009 |
5.5
|
A |
| 245 |
HIGH DISCOVERY
IMO 9674725
|
45,999 | 2014 |
5.5
|
A |
| 249 |
ECO MARINA DEL REY
IMO 9798349
|
50,267 | 2019 |
5.5
|
A |
| 248 |
CHALLENGE PRIME
IMO 9793272
|
49,932 | 2017 |
5.5
|
A |
| 247 |
RAWAN
IMO 9845104
|
55,634 | 2020 |
5.5
|
A |
| 250 |
ISLEMAN
IMO 9391440
|
49,999 | 2009 |
5.5
|
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.