Most Emission-Efficient LNG Carriers
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 |
MARAN GAS ITHACA
IMO 9892717
|
93,080 | 2021 |
5.5
|
B |
| 152 |
CELSIUS GLARUS
IMO 9945459
|
92,385 | 2024 |
5.5
|
B |
| 153 |
LNG ROSENROT
IMO 9877133
|
98,936 | 2021 |
5.5
|
B |
| 154 |
IGNACY JAN PADEREWSKI
IMO 9969388
|
95,440 | 2025 |
5.5
|
C |
| 155 |
MINERVA LIMNOS
IMO 9854375
|
94,834 | 2021 |
5.5
|
C |
| 156 |
EMEI
IMO 9958640
|
91,557 | 2023 |
5.5
|
C |
| 157 |
JOZEF PILSUDSKI
IMO 9969376
|
95,440 | 2025 |
5.5
|
C |
| 158 |
MARAN GAS ACHILLES
IMO 9682588
|
92,713 | 2016 |
5.6
|
C |
| 159 |
HLS CARTAGENA
IMO 9947691
|
94,927 | 2024 |
5.6
|
C |
| 160 |
PACIFIC SUCCESS
IMO 9903425
|
88,624 | 2027 |
5.6
|
C |
| 161 |
GLOBAL STAR
IMO 9859741
|
94,732 | 2021 |
5.6
|
C |
| 162 |
PARIS KNUTSEN
IMO 9946350
|
95,548 | 2023 |
5.6
|
C |
| 163 |
SOHSHU MARU
IMO 9791212
|
82,254 | 2019 |
5.6
|
C |
| 164 |
HUASHAN
IMO 9958652
|
91,753 | 2024 |
5.6
|
C |
| 165 |
AL QA'IYYAH
IMO 9976812
|
88,877 | 2024 |
5.6
|
C |
| 166 |
ORION SEA
IMO 9889904
|
88,592 | 2022 |
5.6
|
C |
| 167 |
MARVEL SWAN
IMO 9880192
|
88,831 | 2021 |
5.6
|
C |
| 168 |
MINERVA AMORGOS
IMO 9885855
|
88,235 | 2022 |
5.6
|
C |
| 169 |
ORION IRIS
IMO 9956604
|
87,921 | 2024 |
5.6
|
C |
| 170 |
MUREX
IMO 9705641
|
95,235 | 2017 |
5.6
|
C |
| 171 |
LNG ENDEAVOUR
IMO 9893606
|
88,798 | 2021 |
5.6
|
C |
| 172 |
GUI YING
IMO 9878888
|
91,497 | 2021 |
5.7
|
C |
| 173 |
LNG GENEVA
IMO 9892133
|
91,305 | 2023 |
5.7
|
C |
| 174 |
BW TULIP
IMO 9758064
|
90,522 | 2018 |
5.7
|
C |
| 175 |
QUEST KIRISHIMA
IMO 9963853
|
87,900 | 2024 |
5.7
|
C |
| 176 |
GAIL BHUWAN
IMO 9877145
|
98,882 | 2021 |
5.7
|
C |
| 177 |
LNG ENDURANCE
IMO 9874492
|
88,721 | 2021 |
5.7
|
C |
| 178 |
ENERGY INNOVATOR
IMO 9758832
|
88,668 | 2019 |
5.7
|
C |
| 179 |
ORION MONET
IMO 9888766
|
88,779 | 2022 |
5.7
|
C |
| 180 |
GASLOG HOUSTON
IMO 9748899
|
92,345 | 2018 |
5.7
|
C |
| 181 |
UMM SWAYYAH
IMO 9976915
|
94,325 | 2024 |
5.7
|
C |
| 182 |
VENTURE GATOR
IMO 9956599
|
87,950 | 2024 |
5.7
|
C |
| 183 |
GASLOG WESTMINSTER
IMO 9855812
|
92,799 | 2020 |
5.8
|
C |
| 184 |
BW ENN SNOW LOTUS
IMO 9896921
|
93,980 | 2022 |
5.8
|
C |
| 185 |
KOOL ORCA
IMO 9870525
|
92,969 | 2021 |
5.8
|
C |
| 186 |
LNG BONNY II
IMO 9692002
|
98,954 | 2015 |
5.8
|
C |
| 187 |
FLEX AMBER
IMO 9857377
|
93,624 | 2020 |
5.8
|
C |
| 188 |
GAIL URJA
IMO 9949027
|
93,758 | 2023 |
5.8
|
C |
| 189 |
SHINSHU MARU
IMO 9791200
|
82,287 | 2019 |
5.8
|
C |
| 190 |
SK AUDACE
IMO 9693161
|
94,665 | 2017 |
5.8
|
C |
| 191 |
FLEX VOLUNTEER
IMO 9862463
|
93,608 | 2021 |
5.8
|
C |
| 192 |
MARAN GAS ALEXANDRIA
IMO 9650054
|
90,494 | 2015 |
5.8
|
C |
| 193 |
VIVIT AFRICA LNG
IMO 9950105
|
92,855 | 2023 |
5.9
|
C |
| 194 |
BW LESMES
IMO 9873840
|
88,907 | 2021 |
5.9
|
C |
| 195 |
LNG LAGOS II
IMO 9692014
|
99,025 | 2016 |
5.9
|
C |
| 196 |
LNG ABUJA II
IMO 9690169
|
87,147 | 2016 |
5.9
|
C |
| 197 |
SEAPEAK VANCOUVER
IMO 9721401
|
95,253 | 2017 |
5.9
|
C |
| 198 |
ENERGY INTELLIGENCE
IMO 9881201
|
94,649 | 2021 |
5.9
|
C |
| 199 |
MARAN GAS HECTOR
IMO 9682605
|
92,640 | 2016 |
5.9
|
C |
| 200 |
FLEX ENTERPRISE
IMO 9762273
|
85,000 | 2018 |
5.9
|
C |
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.