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 |
|---|---|---|---|---|---|
| 202 |
FRONT CROWN
IMO 9759757
|
157,460 | 2016 |
2.5
|
A |
| 201 |
DELTA TOLMI
IMO 9429027
|
157,487 | 2010 |
2.5
|
A |
| 206 |
SEA GALAXY
IMO 9935648
|
156,733 | 2020 |
2.5
|
A |
| 205 |
SONANGOL NAMIBE
IMO 9325049
|
158,425 | 2007 |
2.5
|
A |
| 204 |
SEA ICON
IMO 9806615
|
156,559 | 2017 |
2.5
|
A |
| 203 |
TAIPAN
IMO 9996393
|
159,076 | 2024 |
2.5
|
A |
| 207 |
SFL FRASER
IMO 9874258
|
158,060 | 2018 |
2.5
|
A |
| 210 |
MARAN PLATO
IMO 9399507
|
158,267 | 2009 |
2.5
|
A |
| 212 |
MARAN PHOEBE
IMO 9868156
|
157,946 | 2020 |
2.5
|
A |
| 209 |
FRONT COSMOS
IMO 9769817
|
157,528 | 2017 |
2.5
|
A |
| 208 |
NORDIC STAR
IMO 9748679
|
157,737 | 2016 |
2.5
|
A |
| 211 |
MARAN HERCULES
IMO 9761360
|
157,755 | 2014 |
2.5
|
A |
| 213 |
ZENITH SPIRIT
IMO 9404845
|
159,952 | 2009 |
2.5
|
A |
| 215 |
AQUABLISS
IMO 9922835
|
157,746 | 2022 |
2.5
|
A |
| 214 |
PLATA LUCKY
IMO 9358292
|
307,284 | 2009 |
2.5
|
A |
| 220 |
SYDNEY SPIRIT
IMO 9594781
|
158,542 | 2012 |
2.5
|
A |
| 219 |
SEA AMBER
IMO 9772931
|
158,455 | 2016 |
2.5
|
A |
| 218 |
LONDON SPIRIT
IMO 9594779
|
158,510 | 2011 |
2.5
|
A |
| 217 |
SAN JACINTO
IMO 9730373
|
158,734 | 2014 |
2.5
|
A |
| 216 |
SFL ALBANY
IMO 9874246
|
158,060 | 2020 |
2.5
|
A |
| 221 |
AEGEAN DREAM
IMO 9645425
|
158,888 | 2016 |
2.5
|
A |
| 224 |
ELANDRA EAGLE
IMO 9792474
|
157,554 | 2017 |
2.5
|
A |
| 223 |
SEAWAYS MONTAUK
IMO 9779537
|
158,432 | 2017 |
2.5
|
A |
| 225 |
SEA ONYX
IMO 9922108
|
156,646 | 2022 |
2.5
|
A |
| 222 |
SEA CORAL
IMO 9935650
|
156,674 | 2022 |
2.5
|
A |
| 226 |
MARAN LEO
IMO 9602473
|
319,450 | 2010 |
2.5
|
A |
| 227 |
POPI SAZAKLIS
IMO 9817494
|
157,610 | 2018 |
2.5
|
A |
| 228 |
SUMMIT SPIRIT
IMO 9404833
|
159,955 | 2008 |
2.5
|
A |
| 229 |
ATLANTA SPIRIT
IMO 9578646
|
158,650 | 2011 |
2.5
|
A |
| 231 |
CYAN NOVA
IMO 9534004
|
318,663 | 2011 |
2.5
|
A |
| 230 |
SONANGOL KULUMBIMBI
IMO 9938482
|
157,663 | 2023 |
2.5
|
A |
| 235 |
FRONT CASCADE
IMO 9769829
|
157,434 | 2017 |
2.6
|
A |
| 234 |
SONANGOL CAZENGA
IMO 9766310
|
156,899 | 2017 |
2.6
|
A |
| 233 |
NORDIC HARRIER
IMO 9921063
|
157,094 | 2020 |
2.6
|
A |
| 232 |
HARMONIC
IMO 9819868
|
159,204 | 2015 |
2.6
|
A |
| 236 |
AEGEAN UNITY
IMO 9745237
|
158,932 | 2014 |
2.6
|
A |
| 239 |
AL RUWAIS
IMO 9828405
|
114,695 | 2021 |
2.6
|
A |
| 238 |
DIMITRI
IMO 9924015
|
157,010 | 2023 |
2.6
|
A |
| 240 |
T.SEMAHAT
IMO 9804148
|
157,453 | 2017 |
2.6
|
A |
| 237 |
AQUAFREEDOM
IMO 9922823
|
157,746 | 2022 |
2.6
|
A |
| 242 |
FRONT CHALLENGER
IMO 9759745
|
157,407 | 2016 |
2.6
|
A |
| 241 |
FRONT SHANGHAI
IMO 9832262
|
158,006 | 2019 |
2.6
|
A |
| 243 |
ARAGONA
IMO 9513115
|
319,319 | 2012 |
2.6
|
A |
| 244 |
DINO
IMO 9923994
|
157,010 | 2022 |
2.6
|
A |
| 247 |
ELISABETH MAERSK
IMO 9682980
|
158,277 | 2017 |
2.6
|
A |
| 246 |
NEW ASPIRE
IMO 9486544
|
296,633 | 2011 |
2.6
|
A |
| 245 |
COBALT NOVA
IMO 9534028
|
299,989 | 2011 |
2.6
|
A |
| 250 |
GULF SUNRISE
IMO 9788887
|
301,528 | 2017 |
2.6
|
A |
| 249 |
OLYMPIC FIGHTER
IMO 9745263
|
158,932 | 2014 |
2.6
|
A |
| 248 |
FRONT SAMARA
IMO 9845130
|
158,018 | 2017 |
2.6
|
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 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.