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 |
|---|---|---|---|---|---|
| 1601 |
HISTRIA CROWN
IMO 9607629
|
40,390 | 2012 |
9.0
|
E |
| 1602 |
ATLANTIC T
IMO 9403322
|
45,989 | 2009 |
9.0
|
E |
| 1603 |
SAN FELIX
IMO 9314868
|
37,312 | 2007 |
9.0
|
E |
| 1604 |
STARLIGHT I
IMO 9377664
|
37,824 | 2007 |
9.0
|
E |
| 1605 |
STI ROTHERHITHE
IMO 9706475
|
38,734 | 2015 |
9.0
|
E |
| 1606 |
DAN SABIA
IMO 9513438
|
59,317 | 2012 |
9.1
|
E |
| 1607 |
PUTUOSHAN
IMO 9286542
|
19,822 | 2004 |
9.1
|
E |
| 1608 |
DAN CISNE
IMO 9513440
|
59,335 | 2011 |
9.1
|
E |
| 1609 |
THE BLACKSMITH
IMO 9659660
|
31,289 | 2013 |
9.1
|
E |
| 1610 |
MELORIA
IMO 9292280
|
40,157 | 2006 |
9.2
|
E |
| 1611 |
MINERVA VASO
IMO 9318008
|
50,921 | 2003 |
9.2
|
E |
| 1612 |
KRITI ROCK
IMO 9392315
|
45,920 | 2008 |
9.2
|
E |
| 1613 |
ZEAL START
IMO 9379064
|
41,369 | 2009 |
9.3
|
E |
| 1614 |
SEACOD
IMO 9352315
|
40,559 | 2006 |
9.3
|
E |
| 1615 |
EAGLE BARENTS
IMO 9676125
|
119,690 | 2015 |
9.3
|
E |
| 1616 |
OSAKA
IMO 9380570
|
37,923 | 2008 |
9.3
|
E |
| 1617 |
BIT WIND
IMO 9904053
|
13,823 | 2022 |
9.3
|
E |
| 1618 |
AMBER BEE
IMO 9316608
|
40,083 | 2004 |
9.3
|
E |
| 1619 |
NEW FRIENDSHIP
IMO 9249180
|
104,801 | 2003 |
9.3
|
E |
| 1620 |
PHOENIX AN
IMO 9299496
|
38,512 | 2005 |
9.3
|
E |
| 1621 |
STI BATTERSEA
IMO 9691723
|
38,734 | 2014 |
9.4
|
E |
| 1622 |
VALSESIA
IMO 9385178
|
37,481 | 2008 |
9.4
|
E |
| 1623 |
COSTANZA M
IMO 9436680
|
40,042 | 2009 |
9.4
|
E |
| 1624 |
MAERSK KATARINA
IMO 9431290
|
39,723 | 2011 |
9.4
|
E |
| 1625 |
VALTELLINA
IMO 9384136
|
37,481 | 2008 |
9.4
|
E |
| 1626 |
CHEM SELENIUM
IMO 9817509
|
19,998 | 2018 |
9.4
|
E |
| 1627 |
ANDROMEDA
IMO 9315795
|
39,378 | 2007 |
9.4
|
E |
| 1628 |
AEGEAS
IMO 9315800
|
39,378 | 2007 |
9.4
|
E |
| 1629 |
YURIY KUCHIEV
IMO 9804033
|
52,292 | 2019 |
9.5
|
E |
| 1630 |
SOUTHERN QUOKKA
IMO 9792010
|
26,077 | 2017 |
9.5
|
E |
| 1631 |
WINNIPEG
IMO 9852133
|
28,627 | 2019 |
9.5
|
E |
| 1632 |
STI COMANDANTE
IMO 9686857
|
38,734 | 2014 |
9.5
|
E |
| 1633 |
CHRYSOPIGI
IMO 9303728
|
38,554 | 2006 |
9.5
|
E |
| 1634 |
MINERVA LYDIA
IMO 9262900
|
47,999 | 2004 |
9.6
|
E |
| 1635 |
YASH
IMO 9231183
|
37,320 | 2002 |
9.6
|
E |
| 1636 |
HELENE MAERSK
IMO 9389514
|
38,016 | 2010 |
9.6
|
E |
| 1637 |
CHEM BARIUM
IMO 9838670
|
19,999 | 2019 |
9.6
|
E |
| 1638 |
SEAVALOUR
IMO 9315771
|
46,702 | 2007 |
9.6
|
E |
| 1639 |
SEATROUT
IMO 9352303
|
40,600 | 2006 |
9.6
|
E |
| 1640 |
YUKON
IMO 9852145
|
28,627 | 2020 |
9.6
|
E |
| 1641 |
YANBU
IMO 9376816
|
38,374 | 2008 |
9.6
|
E |
| 1642 |
HENNING MAERSK
IMO 9389526
|
38,001 | 2010 |
9.6
|
E |
| 1643 |
EMERALD
IMO 9391945
|
47,302 | 2009 |
9.7
|
E |
| 1644 |
FAIR WINDS
IMO 9327009
|
73,976 | 2007 |
9.7
|
E |
| 1645 |
ANWAAR AFRIQYA
IMO 9275268
|
34,656 | 2004 |
9.7
|
E |
| 1646 |
DINA F
IMO 9367750
|
47,401 | 2009 |
9.7
|
E |
| 1647 |
HANS MAERSK
IMO 9389497
|
37,961 | 2009 |
9.8
|
E |
| 1648 |
VALLE DI CORDOBA
IMO 9295311
|
39,990 | 2005 |
9.8
|
E |
| 1649 |
XT PROSPERITY
IMO 9989560
|
13,185 | 2024 |
9.8
|
E |
| 1650 |
SOUTHERN OWL
IMO 9773143
|
26,057 | 2016 |
9.8
|
E |
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.