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 |
|---|---|---|---|---|---|
| 1251 |
SEAWAYS JEJU
IMO 9700471
|
50,072 | 2015 |
5.4
|
D |
| 1252 |
SEVERN
IMO 9859234
|
50,192 | 2021 |
5.4
|
D |
| 1253 |
LAKE STARS
IMO 9868780
|
113,848 | 2020 |
5.4
|
D |
| 1254 |
PACIFIC SENTINEL
IMO 9862932
|
50,332 | 2019 |
5.4
|
D |
| 1255 |
HARRISBURG
IMO 9859210
|
50,192 | 2020 |
5.4
|
D |
| 1256 |
SOLAR MELISSA
IMO 9882401
|
49,999 | 2020 |
5.4
|
D |
| 1257 |
PROMITHEAS
IMO 9305611
|
117,055 | 2006 |
5.4
|
D |
| 1258 |
AMALTHEA
IMO 9298650
|
107,115 | 2006 |
5.4
|
D |
| 1259 |
RYMAN
IMO 9777931
|
113,000 | 2017 |
5.4
|
D |
| 1260 |
VELOS FORTUNA
IMO 9347310
|
47,286 | 2007 |
5.5
|
D |
| 1261 |
SOLAR KATHERINE
IMO 9882396
|
49,990 | 2020 |
5.5
|
D |
| 1262 |
JANINE K
IMO 9544607
|
48,045 | 2009 |
5.5
|
D |
| 1263 |
HAFNIA EXCELLENCE
IMO 9735646
|
74,613 | 2016 |
5.5
|
D |
| 1264 |
SEA TIGER
IMO 9834870
|
49,821 | 2019 |
5.5
|
D |
| 1265 |
PEARY SPIRIT
IMO 9466130
|
109,325 | 2011 |
5.5
|
D |
| 1266 |
SILVER HOUSTON
IMO 9683403
|
49,746 | 2012 |
5.5
|
D |
| 1267 |
TORM SOLUTION
IMO 9836050
|
49,999 | 2019 |
5.5
|
D |
| 1268 |
FLORA MARIS
IMO 9423906
|
50,179 | 2008 |
5.5
|
D |
| 1269 |
EVERGREEN MARINER
IMO 9902873
|
50,275 | 2019 |
5.5
|
D |
| 1270 |
NAVIG8 HONOR
IMO 9556181
|
75,000 | 2011 |
5.5
|
D |
| 1271 |
TORM STELLAR
IMO 9854806
|
49,954 | 2020 |
5.5
|
D |
| 1272 |
LR1 AMBASSADOR
IMO 9307085
|
73,584 | 2007 |
5.5
|
D |
| 1273 |
BANDA
IMO 9337406
|
105,576 | 2007 |
5.5
|
D |
| 1274 |
DUBAI GOLD
IMO 9314193
|
73,580 | 2007 |
5.5
|
D |
| 1275 |
NAVIG8 PROMISE
IMO 9791298
|
109,992 | 2015 |
5.5
|
D |
| 1276 |
TORM ATLANTIC
IMO 9433509
|
49,999 | 2010 |
5.5
|
D |
| 1277 |
SAFEEN STRENGTH
IMO 9543524
|
104,594 | 2012 |
5.5
|
D |
| 1278 |
STI MARVEL
IMO 9829473
|
47,499 | 2017 |
5.5
|
D |
| 1279 |
ATHINA
IMO 9389564
|
74,999 | 2008 |
5.5
|
D |
| 1280 |
SEA QUEST
IMO 9629940
|
49,990 | 2012 |
5.5
|
D |
| 1281 |
SEA COUGAR
IMO 9834868
|
49,910 | 2019 |
5.5
|
D |
| 1282 |
PALERMO
IMO 9414292
|
53,540 | 2010 |
5.5
|
D |
| 1283 |
MRC LIVA
IMO 9629964
|
49,967 | 2012 |
5.5
|
D |
| 1284 |
STI PONTIAC
IMO 9704465
|
49,990 | 2015 |
5.5
|
D |
| 1285 |
HANSA SEALANCER
IMO 9367695
|
47,451 | 2008 |
5.5
|
D |
| 1286 |
TORM LENE
IMO 9390769
|
53,143 | 2008 |
5.6
|
D |
| 1287 |
STI LEBLON
IMO 9785706
|
49,990 | 2017 |
5.6
|
D |
| 1288 |
JAG PRIYA
IMO 9425514
|
49,999 | 2010 |
5.6
|
D |
| 1289 |
HARDRADA
IMO 9344007
|
45,983 | 2007 |
5.6
|
D |
| 1290 |
PGC ALEXANDRIA
IMO 9336505
|
74,996 | 2006 |
5.6
|
D |
| 1291 |
SEASONG
IMO 9290438
|
105,459 | 2005 |
5.6
|
D |
| 1292 |
WISCO ADVENTURE
IMO 9858852
|
49,949 | 2021 |
5.6
|
D |
| 1293 |
SANDPIPER PACIFIC
IMO 9648192
|
51,833 | 2013 |
5.6
|
D |
| 1294 |
LIA
IMO 9417751
|
73,723 | 2008 |
5.6
|
D |
| 1295 |
MEZAIRA'A
IMO 9487275
|
74,854 | 2011 |
5.6
|
D |
| 1296 |
STI YORKVILLE
IMO 9688350
|
49,990 | 2014 |
5.6
|
D |
| 1297 |
TORM ASLAUG
IMO 9465978
|
49,999 | 2010 |
5.6
|
D |
| 1298 |
HANSA SEALEADER
IMO 9367712
|
47,463 | 2008 |
5.6
|
D |
| 1299 |
STRENGTH
IMO 9418145
|
50,497 | 2009 |
5.6
|
D |
| 1300 |
HIGH TRANSPORTER
IMO 9812743
|
51,504 | 2017 |
5.6
|
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.