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 |
|---|---|---|---|---|---|
| 151 |
ST GEORGE
IMO 9412775
|
50,651 | 2010 |
5.2
|
A |
| 152 |
STENA PRO PATRIA
IMO 9899727
|
49,990 | 2022 |
5.2
|
A |
| 155 |
SILVER EMILY
IMO 9682356
|
49,746 | 2014 |
5.2
|
A |
| 154 |
HAFNIA KIRSTEN
IMO 9732682
|
49,999 | 2017 |
5.2
|
A |
| 153 |
ECOMAR GASCOGNE
IMO 1029261
|
49,776 | 2025 |
5.2
|
A |
| 157 |
JUPITER STAR
IMO 9919632
|
50,434 | 2021 |
5.2
|
A |
| 156 |
CYPRESS SUN
IMO 9911551
|
49,999 | 2023 |
5.2
|
A |
| 158 |
OINOUSSIAN STAR
IMO 9827578
|
49,999 | 2018 |
5.2
|
A |
| 159 |
HAFNIA VIRIDIAN
IMO 9690614
|
49,126 | 2015 |
5.2
|
A |
| 160 |
NORD MARINER
IMO 9941300
|
49,999 | 2023 |
5.2
|
A |
| 162 |
LONE STAR MARINER
IMO 9902859
|
50,275 | 2021 |
5.2
|
A |
| 161 |
STENA CONQUEST
IMO 1013963
|
49,948 | 2025 |
5.2
|
A |
| 163 |
BLUE BUTTERFLY
IMO 9788576
|
49,995 | 2019 |
5.2
|
A |
| 164 |
STI MIGHTY
IMO 9854739
|
47,499 | 2020 |
5.2
|
A |
| 165 |
TORM TROILUS
IMO 9726475
|
49,757 | 2016 |
5.2
|
A |
| 168 |
SOLAR CHERYL
IMO 9898503
|
49,389 | 2021 |
5.2
|
A |
| 167 |
AVENCA
IMO 9410002
|
51,237 | 2008 |
5.2
|
A |
| 166 |
STENA IMPORTANT
IMO 9667497
|
49,731 | 2015 |
5.2
|
A |
| 170 |
NORD VANQUISH
IMO 9833058
|
50,338 | 2017 |
5.2
|
A |
| 169 |
SOLAR RUO YUN
IMO 9907811
|
49,362 | 2021 |
5.2
|
A |
| 172 |
NORD VIRAGE
IMO 9944132
|
50,378 | 2022 |
5.2
|
A |
| 171 |
NAVIG8 GRACE
IMO 9833656
|
49,804 | 2019 |
5.2
|
A |
| 173 |
SEAWAYS WARWICK
IMO 9717761
|
49,990 | 2015 |
5.3
|
A |
| 175 |
LUCKY CHEMIST
IMO 9686742
|
49,990 | 2015 |
5.3
|
A |
| 174 |
CLEAROCEAN MAGIC
IMO 9849382
|
49,995 | 2019 |
5.3
|
A |
| 178 |
HIGH NAVIGATOR
IMO 9814143
|
49,921 | 2018 |
5.3
|
A |
| 177 |
DANK SILVER
IMO 9718806
|
49,734 | 2016 |
5.3
|
A |
| 176 |
CAPE AVANTI
IMO 9995430
|
50,516 | 2025 |
5.3
|
A |
| 179 |
MADHA SILVER
IMO 9718818
|
45,923 | 2016 |
5.3
|
A |
| 181 |
ZAHRA
IMO 9917866
|
55,202 | 2022 |
5.3
|
A |
| 180 |
BOW TRIDENT
IMO 9669897
|
49,622 | 2014 |
5.3
|
A |
| 182 |
CATHERINE GRACE
IMO 9724611
|
50,099 | 2016 |
5.3
|
A |
| 183 |
MAHADAH SILVER
IMO 9718777
|
45,923 | 2016 |
5.3
|
A |
| 185 |
SOLAR SUSIE
IMO 9898515
|
49,360 | 2021 |
5.3
|
A |
| 184 |
STI MODEST
IMO 9833577
|
49,999 | 2019 |
5.3
|
A |
| 190 |
STI MILLENNIA
IMO 9829497
|
47,499 | 2019 |
5.3
|
A |
| 189 |
NORD MAVERICK
IMO 9877559
|
50,185 | 2020 |
5.3
|
A |
| 188 |
YASA SWAN
IMO 9857248
|
50,215 | 2019 |
5.3
|
A |
| 187 |
ECO YOSEMITE PARK
IMO 9877573
|
49,999 | 2020 |
5.3
|
A |
| 186 |
TORM AMALIE
IMO 9466025
|
49,999 | 2011 |
5.3
|
A |
| 191 |
TORM LENE
IMO 9390769
|
53,143 | 2008 |
5.3
|
A |
| 192 |
TORM DAVAO
IMO 9688350
|
49,990 | 2014 |
5.3
|
A |
| 193 |
NAVIG8 GALLANTRY
IMO 9833668
|
49,759 | 2019 |
5.3
|
A |
| 196 |
FPMC 36
IMO 9845180
|
49,721 | 2020 |
5.3
|
A |
| 195 |
NAVIG8 EXPRESS
IMO 9976874
|
49,153 | 2024 |
5.3
|
A |
| 194 |
NORD MATE
IMO 1013949
|
49,999 | 2025 |
5.3
|
A |
| 199 |
AL AMERAT
IMO 9405851
|
51,022 | 2008 |
5.4
|
A |
| 198 |
HIGH TRUST
IMO 9696254
|
49,990 | 2016 |
5.4
|
A |
| 197 |
ECOMAR GUYENNE
IMO 1029273
|
49,763 | 2025 |
5.4
|
A |
| 200 |
BOUGAINVILLE
IMO 9581693
|
50,626 | 2013 |
5.4
|
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.