Most Emission-Efficient Chemical 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 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 |
|---|---|---|---|---|---|
| 1351 |
SCANDIC
IMO 9386249
|
11,505 | 2007 |
18.3
|
E |
| 1352 |
NQ ZINNIA
IMO 9150327
|
10,128 | 1998 |
18.4
|
E |
| 1353 |
KONGO STAR
IMO 9508823
|
13,011 | 2010 |
18.4
|
E |
| 1354 |
MANAS
IMO 9447055
|
10,745 | 2008 |
18.5
|
E |
| 1355 |
ANTON
IMO 9514456
|
8,402 | 2010 |
18.5
|
E |
| 1356 |
IVER AMBITION
IMO 9439163
|
9,228 | 2009 |
18.6
|
E |
| 1357 |
WILHELMINE ESSBERGER
IMO 9295440
|
8,631 | 2005 |
18.6
|
E |
| 1358 |
SCOT FRANKFURT
IMO 9274537
|
8,182 | 2005 |
18.6
|
E |
| 1359 |
COSIMA PG
IMO 9857822
|
7,392 | 2019 |
18.6
|
E |
| 1360 |
OWL 4
IMO 9435557
|
13,075 | 2006 |
18.7
|
E |
| 1361 |
ELARA
IMO 9309148
|
11,276 | 2006 |
18.9
|
E |
| 1362 |
SCOT DRESDEN
IMO 9365245
|
8,158 | 2007 |
18.9
|
E |
| 1363 |
VIVA
IMO 9156539
|
16,116 | 1999 |
18.9
|
E |
| 1364 |
DENSA DERYA
IMO 9367358
|
8,011 | 2008 |
18.9
|
E |
| 1365 |
TRANS EMERALD
IMO 9295452
|
8,650 | 2005 |
19.0
|
E |
| 1366 |
LAMENTIN
IMO 9377054
|
11,320 | 2007 |
19.0
|
E |
| 1367 |
MURRAY STAR
IMO 9527635
|
13,006 | 2011 |
19.0
|
E |
| 1368 |
KARRUCA
IMO 9216470
|
7,721 | 2001 |
19.1
|
E |
| 1369 |
GTM DENMARK
IMO 9528902
|
11,596 | 2011 |
19.1
|
E |
| 1370 |
OLYMPUS
IMO 9310355
|
9,189 | 2006 |
19.1
|
E |
| 1371 |
HELGA ESSBERGER
IMO 9172155
|
9,887 | 1999 |
19.1
|
E |
| 1372 |
DH BLOSSOMING
IMO 9813046
|
8,702 | 2018 |
19.2
|
E |
| 1373 |
CAROLINE ESSBERGER
IMO 9439151
|
8,506 | 2009 |
19.2
|
E |
| 1374 |
ANNETTE ESSBERGER
IMO 9327059
|
11,340 | 2006 |
19.2
|
E |
| 1375 |
AMUR STAR
IMO 9480368
|
13,019 | 2010 |
19.2
|
E |
| 1376 |
ARABELLA
IMO 9909247
|
7,703 | 2021 |
19.3
|
E |
| 1377 |
ERICUSA M
IMO 9367372
|
18,000 | 2009 |
19.3
|
E |
| 1378 |
AGNES ESSBERGER
IMO 9327047
|
11,340 | 2006 |
19.3
|
E |
| 1379 |
HABIP BAYRAK
IMO 9458183
|
8,404 | 2010 |
19.5
|
E |
| 1380 |
BASAT
IMO 9447029
|
10,745 | 2008 |
19.6
|
E |
| 1381 |
ENDO OSTRO
IMO 9393656
|
7,335 | 2008 |
19.6
|
E |
| 1382 |
LIA IEVOLI
IMO 9148582
|
9,976 | 1999 |
19.6
|
E |
| 1383 |
SIGRID THERESA
IMO 9392183
|
8,139 | 2008 |
19.6
|
E |
| 1384 |
SPRING S
IMO 9416812
|
13,021 | 2009 |
19.6
|
E |
| 1385 |
NQ LILIUM
IMO 9393395
|
8,110 | 2009 |
19.7
|
E |
| 1386 |
EFE
IMO 9558763
|
7,623 | 2010 |
19.7
|
E |
| 1387 |
IEVOLI SHINE
IMO 9172167
|
9,887 | 1998 |
19.8
|
E |
| 1388 |
NORDSTRAUM
IMO 9523548
|
9,616 | 2012 |
19.8
|
E |
| 1389 |
CARIBE MARIA
IMO 9337286
|
11,299 | 2007 |
19.9
|
E |
| 1390 |
KATELINA
IMO 9485368
|
8,933 | 2014 |
20.3
|
E |
| 1391 |
GISELA ESSBERGER
IMO 9147734
|
9,554 | 1998 |
20.3
|
E |
| 1392 |
HACI FATMA ANA
IMO 9458195
|
8,424 | 2011 |
20.4
|
E |
| 1393 |
GIOIA MIA
IMO 9321419
|
8,057 | 2006 |
20.4
|
E |
| 1394 |
MED PAKIZE
IMO 9830604
|
8,219 | 2020 |
20.4
|
E |
| 1395 |
STOC NIKE
IMO 9431032
|
7,770 | 2009 |
20.4
|
E |
| 1396 |
GIOCONDA
IMO 9819052
|
7,746 | 2018 |
20.4
|
E |
| 1397 |
FIYUH
IMO 9499371
|
26,215 | 2011 |
20.4
|
E |
| 1398 |
DUZGIT ENDEAVOUR
IMO 9581007
|
15,995 | 2013 |
20.5
|
E |
| 1399 |
NQ LAELIA
IMO 9393383
|
8,115 | 2008 |
20.5
|
E |
| 1400 |
MED SERHAT
IMO 9461922
|
8,263 | 2020 |
20.5
|
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.