Most Emission-Efficient Oil 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 2024. 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 |
|---|---|---|---|---|---|
| 1101 |
CASPIAN SEA
IMO 9829095
|
114,218 | 2019 |
4.8
|
D |
| 1102 |
SEASTAR
IMO 9373656
|
116,049 | 2008 |
4.8
|
D |
| 1103 |
OHIO
IMO 9417440
|
105,188 | 2009 |
4.8
|
D |
| 1104 |
ATROTOS
IMO 9953432
|
50,113 | 2023 |
4.8
|
D |
| 1105 |
CABO FUJI
IMO 9730878
|
74,246 | 2017 |
4.8
|
D |
| 1106 |
STI DONALD C TRAUSCHT
IMO 9794422
|
51,260 | 2017 |
4.8
|
D |
| 1107 |
OLYMPIC SEA
IMO 9489285
|
104,808 | 2008 |
4.8
|
D |
| 1108 |
AL ADAILIAH
IMO 9856684
|
48,578 | 2020 |
4.8
|
D |
| 1109 |
CURRENT SPIRIT
IMO 9843924
|
129,801 | 2020 |
4.8
|
D |
| 1110 |
ALIAI
IMO 9884813
|
50,315 | 2021 |
4.8
|
D |
| 1111 |
HAFNIA OSPREY
IMO 9682241
|
49,999 | 2015 |
4.8
|
D |
| 1112 |
FLAGSHIP SAGE
IMO 9471329
|
74,158 | 2011 |
4.8
|
D |
| 1113 |
STI MERAUX
IMO 9681118
|
50,300 | 2012 |
4.8
|
D |
| 1114 |
MARALTA
IMO 9324320
|
74,999 | 2007 |
4.8
|
D |
| 1115 |
TORM SUCCESS
IMO 9836048
|
49,976 | 2019 |
4.8
|
D |
| 1116 |
KRITI LEGEND
IMO 9398266
|
107,518 | 2009 |
4.8
|
D |
| 1117 |
JAG PRERANA
IMO 9321952
|
47,848 | 2007 |
4.9
|
D |
| 1118 |
LONE STAR MARINER
IMO 9902859
|
50,275 | 2021 |
4.9
|
D |
| 1119 |
HELLESPONT PROMISE
IMO 9351438
|
73,669 | 2007 |
4.9
|
D |
| 1120 |
PROPONTIS
IMO 9305623
|
117,055 | 2006 |
4.9
|
D |
| 1121 |
ENERGY ARTEMIS
IMO 9928750
|
49,812 | 2022 |
4.9
|
D |
| 1122 |
SIFSAFAH
IMO 9856713
|
48,578 | 2020 |
4.9
|
D |
| 1123 |
IRINI
IMO 9934890
|
49,990 | 2022 |
4.9
|
D |
| 1124 |
LARGO EXCELLENCE
IMO 9935923
|
49,999 | 2023 |
4.9
|
D |
| 1125 |
VOULA
IMO 9488413
|
73,774 | 2006 |
4.9
|
D |
| 1126 |
MARI JONE
IMO 9725316
|
49,999 | 2016 |
4.9
|
D |
| 1127 |
MAERSK CRETE
IMO 9786190
|
49,919 | 2019 |
4.9
|
D |
| 1128 |
HAFNIA THALASSA
IMO 9800324
|
109,990 | 2019 |
4.9
|
D |
| 1129 |
BULL
IMO 9292503
|
115,515 | 2005 |
4.9
|
D |
| 1130 |
SHAHRAZAD
IMO 9389863
|
74,999 | 2009 |
4.9
|
D |
| 1131 |
HAFNIA LIONESS
IMO 9675509
|
49,999 | 2014 |
4.9
|
D |
| 1132 |
AKTEA
IMO 9326512
|
51,371 | 2009 |
4.9
|
D |
| 1133 |
RICH HARVEST
IMO 9908982
|
50,446 | 2021 |
5.0
|
D |
| 1134 |
NORD VULCAN
IMO 9982524
|
49,999 | 2024 |
5.0
|
D |
| 1135 |
EVRIDIKI
IMO 9358929
|
73,740 | 2008 |
5.0
|
D |
| 1136 |
WECO PISCES
IMO 9923932
|
49,999 | 2022 |
5.0
|
D |
| 1137 |
VALFOGLIA
IMO 9417309
|
109,060 | 2009 |
5.0
|
D |
| 1138 |
PACIFIC MOONSTONE
IMO 9892078
|
50,192 | 2021 |
5.0
|
D |
| 1139 |
SILVER MUNA
IMO 9718856
|
50,000 | 2016 |
5.0
|
D |
| 1140 |
P. ALIKI
IMO 9460136
|
105,304 | 2010 |
5.0
|
D |
| 1141 |
CLEAROCEAN MAVERICK
IMO 9900825
|
49,999 | 2021 |
5.0
|
D |
| 1142 |
ADVANTAGE ATOM
IMO 9472622
|
116,014 | 2011 |
5.0
|
D |
| 1143 |
ALATAU
IMO 9416551
|
115,896 | 2009 |
5.0
|
D |
| 1144 |
MONTEGO
IMO 9297553
|
108,402 | 2006 |
5.0
|
D |
| 1145 |
SAVIR TIGER
IMO 9388730
|
108,941 | 2005 |
5.0
|
D |
| 1146 |
SEMERU
IMO 9388376
|
105,777 | 2008 |
5.0
|
D |
| 1147 |
CL VIRGINIA WOOLF
IMO 9943396
|
49,359 | 2024 |
5.0
|
D |
| 1148 |
STAVANGER PRIDE
IMO 9856062
|
49,999 | 2020 |
5.0
|
D |
| 1149 |
EUROPE I
IMO 9905332
|
163,136 | 2022 |
5.0
|
D |
| 1150 |
TORM STRONG
IMO 9836062
|
49,954 | 2019 |
5.0
|
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 2024 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.