Gas Carrier Emissions & Retrofit Radar
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.
CII band distribution
84 at D/E425 rated vessels · 27 of the D/E set dock within 12 months
Docking pipeline — D/E vessels per quarter
Windows estimated from the class-expiry docking model, not bookings.
Top eligible retrofit measures for this segment
| Measure | Eligible | CO₂ reduction | Capex band | Payback | Confidence |
|---|---|---|---|---|---|
| Propeller redesign / replacement | 396 | 5–10% | €400k–1,200k | — | vendor claim |
| Turbocharger cut-out | 207 | 1–3% | €80k–250k | — | vendor claim |
| Shaft generator / PTO | 54 | 3–6% | €500–1,500/kW | — | vendor claim |
Capex bands are indicative vendor/literature priors. Payback appears once price parameters are configured.
Retrofit opportunity in this segment
Retrofit prospects — worst band first
| Vessel | Band | Age | Drop year |
|---|---|---|---|
| GAS VITALITY · <25k | E | 5y | 2026 |
| CONSTELLATION · 25-60k | E | 12y | 2026 |
| PERTAMINAGASAMARYLIS · 25-60k | E | 5y | 2026 |
| CHEIKH BOUAMAMA · 25-60k | E | 18y | 2026 |
| EIGER EXPLORER · 25-60k | E | 7y | 2026 |
| # | Vessel | Size (DWT) | Built | Carbon intensity — AER (g CO₂/dwt·nm) | Grade |
|---|---|---|---|---|---|
| 201 |
ETAGAS
IMO 9553634
|
14,999 | 2014 |
12.3
|
C |
| 202 |
NAVIGATOR VIRGO
IMO 9404819
|
23,723 | 2009 |
12.4
|
C |
| 203 |
INEOS INSPIRATION
IMO 9685451
|
20,916 | 2016 |
12.4
|
C |
| 204 |
NAVIGATOR PLUTO
IMO 9177571
|
23,484 | 2000 |
12.4
|
C |
| 205 |
INEOS INTUITION
IMO 9771523
|
20,716 | 2017 |
12.4
|
C |
| 206 |
INEOS INGENUITY
IMO 9685437
|
20,897 | 2015 |
12.6
|
C |
| 207 |
CLIPPER HERMOD
IMO 9378163
|
18,861 | 2008 |
12.6
|
C |
| 208 |
ALKAID
IMO 9655509
|
22,780 | 2013 |
12.6
|
C |
| 209 |
CLIPPER ENYO
IMO 9827217
|
18,077 | 2019 |
12.7
|
D |
| 210 |
EARTH SUMMIT
IMO 9744946
|
16,940 | 2017 |
12.7
|
D |
| 211 |
CLIPPER EOS
IMO 9827205
|
18,056 | 2019 |
12.8
|
D |
| 212 |
ADRIATIC GAS
IMO 9662021
|
24,286 | 2015 |
12.8
|
D |
| 213 |
NAVIGATOR GUSTO
IMO 9531507
|
16,687 | 2008 |
12.8
|
D |
| 214 |
CLIPPER ERIS
IMO 9834727
|
18,044 | 2019 |
12.9
|
D |
| 215 |
ENABLE
IMO 9900851
|
16,930 | 2023 |
13.0
|
D |
| 216 |
EMPERY
IMO 9744910
|
16,925 | 2016 |
13.1
|
D |
| 217 |
EMILIUS
IMO 9744934
|
16,920 | 2017 |
13.1
|
D |
| 218 |
BERGA II
IMO 9537032
|
26,375 | 2010 |
13.2
|
D |
| 219 |
YARA KARA
IMO 9734836
|
18,208 | 2016 |
13.2
|
D |
| 220 |
YARA NAUMA
IMO 9734848
|
18,208 | 2016 |
13.2
|
D |
| 221 |
RHOURD EL ADRA
IMO 9320855
|
19,392 | 2007 |
13.3
|
D |
| 222 |
EXHIBITIONIST
IMO 9900849
|
16,938 | 2023 |
13.3
|
D |
| 223 |
TRAMMO MARYCAM
IMO 9409168
|
16,772 | 2009 |
13.4
|
D |
| 224 |
CLIPPER HERMES
IMO 9378151
|
18,861 | 2008 |
13.4
|
D |
| 225 |
SANMAR RAGA
IMO 9358682
|
18,110 | 2007 |
13.5
|
D |
| 226 |
NAVIGATOR VESTA
IMO 9402574
|
18,919 | 2009 |
13.5
|
D |
| 227 |
NAVIGATOR LUGA
IMO 9761164
|
19,002 | 2017 |
13.6
|
D |
| 228 |
TRAMMO PARIS
IMO 9792515
|
17,667 | 2017 |
13.6
|
D |
| 229 |
ELECTRA
IMO 9897107
|
16,893 | 2022 |
13.7
|
D |
| 230 |
NAVIGATOR GRACE
IMO 9531478
|
16,687 | 2008 |
13.8
|
D |
| 231 |
BARUMK GAS
IMO 9922225
|
17,872 | 2022 |
13.8
|
D |
| 232 |
NAVIGATOR GALAXY
IMO 9536363
|
16,686 | 2011 |
13.9
|
D |
| 233 |
NAVIGATOR ATLAS
IMO 9661558
|
16,988 | 2014 |
14.0
|
D |
| 234 |
HAPPY OSPREY
IMO 9553646
|
14,995 | 2013 |
14.2
|
D |
| 235 |
NAVIGATOR OBERON
IMO 9671216
|
16,994 | 2014 |
14.2
|
D |
| 236 |
BWEK BEACON
IMO 1019917
|
7,139 | 2025 |
14.4
|
D |
| 237 |
NAVIGATOR GENESIS
IMO 9531519
|
16,686 | 2011 |
14.8
|
D |
| 238 |
HAPPY KESTREL
IMO 9543043
|
15,206 | 2013 |
14.9
|
D |
| 239 |
GAZ ENERGY
IMO 9458169
|
17,674 | 2010 |
15.1
|
D |
| 240 |
HAPPY ALBATROSS
IMO 9675066
|
14,995 | 2015 |
15.2
|
D |
| 241 |
GAZ PROVIDENCE
IMO 9448504
|
17,022 | 2010 |
15.3
|
D |
| 242 |
KITHNOS
IMO 9711523
|
14,999 | 2016 |
15.4
|
D |
| 243 |
BELGRAVIA V
IMO 9341897
|
9,127 | 2006 |
15.5
|
D |
| 244 |
CHEIKH EL MOKRANI
IMO 9324332
|
39,520 | 2007 |
15.6
|
D |
| 245 |
RHOURD EL FARES
IMO 9537044
|
26,353 | 2010 |
15.6
|
D |
| 246 |
NAVIGATOR EUROPA
IMO 9661807
|
17,005 | 2014 |
15.6
|
D |
| 247 |
KALOLIMNOS
IMO 9796705
|
14,999 | 2018 |
15.7
|
D |
| 248 |
EPIC MADEIRA
IMO 9341902
|
9,127 | 2006 |
15.8
|
D |
| 249 |
NAVIGATOR UMBRIO
IMO 9704491
|
17,040 | 2015 |
16.1
|
D |
| 250 |
NAVIGATOR GLOBAL
IMO 9536375
|
16,687 | 2011 |
16.2
|
D |
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.