Most Emission-Efficient Container Ships
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 (TEU) | Built | Carbon intensity — AER (g CO₂/dwt·nm) | Grade |
|---|---|---|---|---|---|
| 2201 |
SUNAID X
IMO 9358539
|
698 TEU | 2006 |
25.6
|
E |
| 2202 |
CMA CGM NADOR
IMO 9396696
|
1,000 TEU | 2007 |
25.6
|
E |
| 2203 |
SCARLETTA
IMO 9449699
|
916 TEU | 2008 |
25.6
|
E |
| 2204 |
CONTSHIP PAX
IMO 9435521
|
1,100 TEU | 2008 |
25.7
|
E |
| 2205 |
X-PRESS MULHACEN
IMO 9365960
|
767 TEU | 2008 |
25.7
|
E |
| 2206 |
VM VITA
IMO 9141118
|
749 TEU | 1996 |
25.8
|
E |
| 2207 |
LAGOA
IMO 9150470
|
375 TEU | 1997 |
25.8
|
E |
| 2208 |
LUCY BORCHARD
IMO 9390824
|
672 TEU | 2006 |
25.8
|
E |
| 2209 |
MSC MANON
IMO 9435820
|
916 TEU | 2008 |
25.8
|
E |
| 2210 |
DREAM
IMO 9322578
|
803 TEU | 2006 |
25.9
|
E |
| 2211 |
WEC MAJORELLE
IMO 9134153
|
700 TEU | 1996 |
26.0
|
E |
| 2212 |
CMA CGM GOYA
IMO 9365972
|
767 TEU | 2008 |
26.1
|
E |
| 2213 |
CT DANIEL
IMO 9326988
|
862 TEU | 2006 |
26.3
|
E |
| 2214 |
JUDITH
IMO 9359260
|
1,440 TEU | 2008 |
26.3
|
E |
| 2215 |
LOUISE BORCHARD
IMO 9336294
|
660 TEU | 2006 |
26.3
|
E |
| 2216 |
HANNI
IMO 9188506
|
658 TEU | 1998 |
26.4
|
E |
| 2217 |
HELENE
IMO 9362956
|
916 TEU | 2007 |
26.4
|
E |
| 2218 |
ALEXANDRA A
IMO 9356684
|
1,022 TEU | 2011 |
26.5
|
E |
| 2219 |
BG ONYX
IMO 9436197
|
803 TEU | 2010 |
26.6
|
E |
| 2220 |
SKOGAFOSS
IMO 9375252
|
698 TEU | 2007 |
26.6
|
E |
| 2221 |
CONTSHIP RAY
IMO 9388338
|
1,080 TEU | 2008 |
26.7
|
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 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.