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 |
|---|---|---|---|---|---|
| 1651 |
VALLE DI GRANADA
IMO 9292278
|
39,999 | 2005 |
9.8
|
E |
| 1652 |
ASPHALT SPIRIT
IMO 9612557
|
14,484 | 2012 |
9.9
|
E |
| 1653 |
ANWAAR AL NASER
IMO 9313450
|
29,006 | 2005 |
9.9
|
E |
| 1654 |
NV APOLLO
IMO 9587790
|
21,306 | 2010 |
10.0
|
E |
| 1655 |
TONDA
IMO 9274654
|
36,803 | 2005 |
10.0
|
E |
| 1656 |
OTTOMANA
IMO 9299214
|
27,836 | 2006 |
10.0
|
E |
| 1657 |
STEEL
IMO 9380594
|
37,538 | 2008 |
10.1
|
E |
| 1658 |
BENTLEY I
IMO 9253129
|
40,081 | 2004 |
10.1
|
E |
| 1659 |
BOW AGATHE
IMO 9393010
|
33,608 | 2009 |
10.1
|
E |
| 1660 |
BORIS SOKOLOV
IMO 9817315
|
51,416 | 2018 |
10.2
|
E |
| 1661 |
VALCADORE
IMO 9384112
|
37,481 | 2008 |
10.2
|
E |
| 1662 |
NOSTOS
IMO 9258014
|
47,147 | 2003 |
10.2
|
E |
| 1663 |
GEA
IMO 9292591
|
39,999 | 2005 |
10.2
|
E |
| 1664 |
STI BRIXTON
IMO 9686869
|
38,734 | 2014 |
10.2
|
E |
| 1665 |
ATLANTIC ASPHALT
IMO 9798428
|
17,763 | 2017 |
10.3
|
E |
| 1666 |
SEARAY
IMO 9255490
|
32,310 | 2004 |
10.4
|
E |
| 1667 |
SEASHARK
IMO 9298193
|
32,302 | 2004 |
10.4
|
E |
| 1668 |
STI ACTON
IMO 9696553
|
38,734 | 2014 |
10.5
|
E |
| 1669 |
BRO NISSUM
IMO 9340623
|
16,674 | 2008 |
10.5
|
E |
| 1670 |
KRITI EPISKOPI
IMO 9340104
|
38,500 | 2006 |
10.5
|
E |
| 1671 |
HENRIETTE MAERSK
IMO 9399349
|
37,985 | 2010 |
10.6
|
E |
| 1672 |
KINGSTON
IMO 9420863
|
38,341 | 2009 |
10.7
|
E |
| 1673 |
SOUTHERN PUMA
IMO 9792008
|
26,071 | 2016 |
10.7
|
E |
| 1674 |
KUBA
IMO 9383089
|
8,525 | 2007 |
10.7
|
E |
| 1675 |
LISBON
IMO 9223916
|
19,783 | 2000 |
10.8
|
E |
| 1676 |
CASTILLO DE ARTEAGA
IMO 9871012
|
37,430 | 2019 |
10.8
|
E |
| 1677 |
T. AYLIN
IMO 9679880
|
19,928 | 2015 |
10.9
|
E |
| 1678 |
SEAMARLIN
IMO 9380489
|
40,549 | 2007 |
10.9
|
E |
| 1679 |
ANWAAR AL KHALIJ
IMO 9313424
|
29,006 | 2005 |
11.0
|
E |
| 1680 |
MERENGUE
IMO 9309980
|
38,431 | 2007 |
11.0
|
E |
| 1681 |
LIFE STAR
IMO 9435325
|
13,030 | 2007 |
11.2
|
E |
| 1682 |
DA MING SHAN
IMO 9779745
|
12,980 | 2016 |
11.3
|
E |
| 1683 |
WONDER MIMOSA
IMO 9312901
|
37,620 | 2006 |
11.3
|
E |
| 1684 |
HAVVA ANA
IMO 9997385
|
8,817 | 2024 |
11.3
|
E |
| 1685 |
WHITE ALLEGRA
IMO 9973353
|
17,779 | 2023 |
11.4
|
E |
| 1686 |
BAGSHOT
IMO 9938987
|
17,933 | 2023 |
11.4
|
E |
| 1687 |
ASENA
IMO 9274628
|
37,188 | 2004 |
11.5
|
E |
| 1688 |
SEASPRAT
IMO 9380477
|
40,598 | 2007 |
11.5
|
E |
| 1689 |
NV MINERVA
IMO 9542166
|
19,992 | 2011 |
11.7
|
E |
| 1690 |
ATRIA
IMO 9492842
|
13,005 | 2010 |
11.7
|
E |
| 1691 |
SEACONGER
IMO 9352298
|
32,200 | 2005 |
11.7
|
E |
| 1692 |
MAERSK KATE
IMO 9431276
|
39,756 | 2010 |
11.8
|
E |
| 1693 |
OASIS II
IMO 9167150
|
34,985 | 2000 |
11.9
|
E |
| 1694 |
MESTRAL
IMO 9391402
|
37,554 | 2008 |
11.9
|
E |
| 1695 |
STEN FRIGG
IMO 9407976
|
16,587 | 2009 |
12.1
|
E |
| 1696 |
T RIGEL
IMO 9585039
|
20,919 | 2021 |
12.3
|
E |
| 1697 |
STEN BOTHNIA
IMO 9378735
|
16,611 | 2008 |
12.4
|
E |
| 1698 |
DA HUA SHAN
IMO 9779757
|
12,972 | 2017 |
12.5
|
E |
| 1699 |
SARACENA
IMO 9334325
|
20,500 | 2007 |
12.6
|
E |
| 1700 |
RINELLA M
IMO 9351529
|
40,441 | 2006 |
12.7
|
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.