Most Emission-Efficient Vehicle 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 |
|---|---|---|---|---|---|
| 151 |
GLOVIS SAFETY
IMO 9798399
|
25,353 | 2017 |
14.4
|
B |
| 152 |
TOMBARRA
IMO 9319753
|
22,149 | 2006 |
14.4
|
B |
| 154 |
HOEGH TRAVELLER
IMO 9710737
|
21,918 | 2016 |
14.4
|
B |
| 153 |
CASSIOPEIA LEADER
IMO 9182277
|
21,547 | 1999 |
14.4
|
B |
| 155 |
HOEGH TRIGGER
IMO 9684988
|
22,088 | 2015 |
14.4
|
B |
| 156 |
MERMAID ACE
IMO 9561289
|
18,828 | 2010 |
14.5
|
B |
| 157 |
APOLLON HIGHWAY
IMO 9728083
|
20,321 | 2017 |
14.5
|
B |
| 158 |
PEONY LEADER
IMO 9985370
|
19,393 | 2025 |
14.5
|
B |
| 159 |
CADWELL
IMO 9999979
|
19,160 | 2025 |
14.5
|
B |
| 160 |
AICC FENGHUANG
IMO 1018391
|
18,878 | 2025 |
14.5
|
B |
| 161 |
PLATINUM RAY
IMO 9210438
|
21,400 | 2000 |
14.5
|
B |
| 163 |
MORNING COMPOSER
IMO 9336074
|
21,053 | 2008 |
14.6
|
B |
| 162 |
HESTIA LEADER
IMO 9355226
|
21,419 | 2008 |
14.6
|
B |
| 165 |
ORION LEADER
IMO 9182289
|
21,526 | 1999 |
14.6
|
B |
| 164 |
TORTUGAS
IMO 9319765
|
22,271 | 2006 |
14.6
|
B |
| 166 |
GLOVIS COSMOS
IMO 9707027
|
20,019 | 2015 |
14.6
|
B |
| 167 |
BYD CHANGZHOU
IMO 9955076
|
19,259 | 2024 |
14.6
|
B |
| 168 |
BOSPORUS HIGHWAY
IMO 9519107
|
18,792 | 2009 |
14.6
|
B |
| 169 |
SAIC ANJI SPLENDOR
IMO 9973365
|
18,162 | 2024 |
14.6
|
B |
| 170 |
OREGON HIGHWAY
IMO 9381665
|
17,699 | 2007 |
14.7
|
B |
| 171 |
CYGNUS LEADER
IMO 9381249
|
20,180 | 2007 |
14.7
|
B |
| 172 |
MORNING LILY
IMO 9446013
|
27,283 | 2011 |
14.7
|
B |
| 173 |
MORNING PROSPERITY
IMO 9780639
|
22,438 | 2017 |
14.7
|
B |
| 174 |
CMA CGM SILVERSTONE
IMO 9953793
|
19,138 | 2024 |
14.7
|
B |
| 175 |
ODIN HIGHWAY
IMO 9948152
|
19,222 | 2024 |
14.7
|
B |
| 176 |
AURIGA LEADER
IMO 9402718
|
18,686 | 2008 |
14.7
|
B |
| 178 |
HERA HIGHWAY
IMO 9982718
|
18,522 | 2025 |
14.7
|
B |
| 177 |
MORNING POST
IMO 9669029
|
22,675 | 2014 |
14.7
|
B |
| 179 |
DIONE LEADER
IMO 9561954
|
21,111 | 2013 |
14.8
|
B |
| 180 |
WILD ROSE LEADER
IMO 9925370
|
19,222 | 2023 |
14.8
|
B |
| 181 |
ANJI SOUNDNESS
IMO 1021398
|
24,670 | 2025 |
14.8
|
B |
| 182 |
ASIAN EMPEROR
IMO 9176632
|
21,472 | 1999 |
14.9
|
B |
| 183 |
MORNING CECILIE
IMO 9477830
|
22,699 | 2008 |
14.9
|
B |
| 184 |
GENTLE LEADER
IMO 9391567
|
21,122 | 2008 |
14.9
|
B |
| 185 |
BYD CHANGSHA
IMO 9993949
|
25,205 | 2025 |
14.9
|
B |
| 187 |
HELIOS LEADER
IMO 9476745
|
18,692 | 2009 |
14.9
|
B |
| 186 |
AH SHIN
IMO 9177430
|
21,503 | 1999 |
14.9
|
B |
| 188 |
NIAGARA HIGHWAY
IMO 9832638
|
21,052 | 2019 |
14.9
|
B |
| 189 |
GREEN BAY
IMO 9339818
|
18,090 | 2007 |
14.9
|
B |
| 190 |
THEMIS LEADER
IMO 9553115
|
20,037 | 2010 |
14.9
|
B |
| 191 |
IGUAZU HIGHWAY
IMO 9827243
|
21,052 | 2018 |
15.0
|
B |
| 192 |
MORNING CHANT
IMO 9663300
|
20,139 | 2014 |
15.0
|
B |
| 193 |
AUTO ASPIRE
IMO 9895812
|
12,452 | 2022 |
15.0
|
C |
| 194 |
MORNING CHAMPION
IMO 9285627
|
21,106 | 2005 |
15.0
|
C |
| 195 |
MERIDIAN ACE
IMO 9209518
|
20,144 | 2000 |
15.0
|
C |
| 197 |
NOCC ATLANTIC
IMO 9430519
|
22,500 | 2009 |
15.1
|
C |
| 196 |
MORNING LAURA
IMO 9445992
|
27,297 | 2010 |
15.1
|
C |
| 198 |
MORNING CORNELIA
IMO 9519145
|
22,530 | 2010 |
15.1
|
C |
| 200 |
SAIC ANJI HARMONY
IMO 9955064
|
19,099 | 2024 |
15.1
|
C |
| 199 |
GLOVIS SUPREME
IMO 9674177
|
20,002 | 2013 |
15.1
|
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.