Most Emission-Efficient Bulk Carriers
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 2025. 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 |
|---|---|---|---|---|---|
| 1701 |
STAR FAIRFIELD
IMO 9575230
|
63,301 | 2013 |
4.4
|
C |
| 1702 |
SV ARISTA
IMO 9566564
|
61,649 | 2011 |
4.4
|
C |
| 1703 |
TRITON
IMO 9642356
|
75,009 | 2012 |
4.4
|
C |
| 1704 |
ROSTRUM ASIA
IMO 9910349
|
40,003 | 2021 |
4.4
|
C |
| 1705 |
GREAT RAINBOW
IMO 9738492
|
63,464 | 2015 |
4.4
|
C |
| 1706 |
ERTEA
IMO 9546198
|
54,876 | 2009 |
4.4
|
C |
| 1707 |
LAKER
IMO 9581368
|
57,399 | 2011 |
4.4
|
C |
| 1708 |
DONALD M. JAMES
IMO 9770555
|
66,454 | 2018 |
4.4
|
C |
| 1709 |
EQUINOX STAR
IMO 9503976
|
58,680 | 2011 |
4.4
|
C |
| 1710 |
ELENA VE
IMO 9453066
|
69,999 | 2010 |
4.4
|
C |
| 1711 |
AFRICAN PUFFIN
IMO 9636448
|
55,863 | 2014 |
4.4
|
C |
| 1712 |
EPIPHANIA
IMO 9582116
|
80,276 | 2012 |
4.4
|
C |
| 1713 |
AROSA
IMO 9244829
|
76,015 | 2001 |
4.4
|
C |
| 1714 |
SPRING LOTUS
IMO 9942110
|
63,539 | 2023 |
4.4
|
C |
| 1715 |
PANAMAX OSTRIA
IMO 9399557
|
76,444 | 2008 |
4.4
|
C |
| 1716 |
UNO
IMO 9423267
|
93,271 | 2009 |
4.4
|
C |
| 1717 |
ALTUS
IMO 9650169
|
58,630 | 2012 |
4.4
|
C |
| 1718 |
ST GREG
IMO 9596179
|
57,949 | 2013 |
4.4
|
C |
| 1719 |
HORIZON JADE
IMO 9579054
|
76,032 | 2011 |
4.4
|
C |
| 1720 |
SUR
IMO 9941611
|
40,076 | 2023 |
4.4
|
C |
| 1721 |
HARVEST
IMO 9297931
|
73,691 | 2005 |
4.4
|
C |
| 1722 |
CYCLADES
IMO 9799616
|
60,384 | 2017 |
4.4
|
C |
| 1723 |
HERMES
IMO 9613056
|
75,200 | 2012 |
4.4
|
C |
| 1724 |
BELLE CONFIDENCE
IMO 9989924
|
40,381 | 2025 |
4.4
|
C |
| 1725 |
CETUS HUMPBACK
IMO 9670731
|
43,479 | 2015 |
4.4
|
C |
| 1726 |
ISSARA NAREE
IMO 9732187
|
64,000 | 2012 |
4.4
|
C |
| 1727 |
MAROULIO S
IMO 9493511
|
76,000 | 2010 |
4.4
|
C |
| 1728 |
HORIZON TRADER
IMO 1014319
|
40,598 | 2025 |
4.4
|
C |
| 1729 |
KOUTALIANOS
IMO 9332016
|
92,710 | 2007 |
4.4
|
C |
| 1730 |
JNS PEACE
IMO 1068994
|
40,502 | 2025 |
4.4
|
C |
| 1731 |
FEDERAL POWER
IMO 9926051
|
42,692 | 2022 |
4.4
|
C |
| 1732 |
ETNA
IMO 9393618
|
48,549 | 2007 |
4.4
|
C |
| 1733 |
MAPLE HARBOUR
IMO 9593323
|
55,832 | 2011 |
4.4
|
C |
| 1734 |
NEW PRESTIGE
IMO 9598206
|
82,044 | 2013 |
4.4
|
C |
| 1735 |
GULMAR
IMO 9146962
|
45,719 | 1997 |
4.4
|
C |
| 1736 |
STAR LUTAS
IMO 9712709
|
61,347 | 2016 |
4.4
|
C |
| 1737 |
XIN HAI TONG 8
IMO 9741566
|
48,897 | 2014 |
4.4
|
C |
| 1738 |
ELIM BOUNCE
IMO 9515096
|
61,616 | 2012 |
4.4
|
C |
| 1739 |
FEDERAL TYNE
IMO 9658903
|
55,160 | 2014 |
4.4
|
C |
| 1740 |
TWIN DELIGHT
IMO 9984481
|
40,656 | 2024 |
4.5
|
C |
| 1741 |
THOR MONADIC
IMO 9331220
|
56,026 | 2006 |
4.5
|
C |
| 1742 |
PITT ISLAND
IMO 9615157
|
61,395 | 2012 |
4.5
|
C |
| 1743 |
SAKAR
IMO 9996953
|
32,195 | 2025 |
4.5
|
C |
| 1744 |
ASTURA
IMO 9994838
|
39,902 | 2024 |
4.5
|
C |
| 1745 |
KYPROS LOYALTY
IMO 9717424
|
77,998 | 2015 |
4.5
|
C |
| 1746 |
DANAE
IMO 9719587
|
81,252 | 2017 |
4.5
|
C |
| 1747 |
SIDER IMABARI
IMO 9984417
|
40,320 | 2024 |
4.5
|
C |
| 1748 |
SHELTER ISLAND
IMO 9426336
|
61,414 | 2011 |
4.5
|
C |
| 1749 |
XIN HAI
IMO 9500950
|
75,380 | 2012 |
4.5
|
C |
| 1750 |
LIGNUM NETWORK
IMO 9942811
|
64,171 | 2022 |
4.5
|
C |
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 2025 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.