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 |
|---|---|---|---|---|---|
| 1201 |
ORIS TRINITY
IMO 9438169
|
13,121 | 2009 |
14.2
|
E |
| 1202 |
PORTOLA
IMO 9449443
|
12,756 | 2010 |
14.2
|
E |
| 1203 |
KOSOVA
IMO 9323792
|
37,320 | 2007 |
14.3
|
E |
| 1204 |
HINCH SPIRIT
IMO 9508940
|
13,965 | 2009 |
14.3
|
E |
| 1205 |
CHEMICAL SAILOR
IMO 9804875
|
12,520 | 2019 |
14.3
|
E |
| 1206 |
FURUHOLMEN
IMO 9553397
|
17,091 | 2010 |
14.3
|
E |
| 1207 |
EKFJORD
IMO 9356622
|
17,006 | 2009 |
14.3
|
E |
| 1208 |
FRANK
IMO 9371787
|
17,998 | 2008 |
14.3
|
E |
| 1209 |
CHEMICAL MARINER
IMO 9558971
|
14,301 | 2010 |
14.3
|
E |
| 1210 |
MORINA THERESA
IMO 9243382
|
16,882 | 2002 |
14.4
|
E |
| 1211 |
SCOT BAYERN
IMO 9255828
|
8,234 | 2003 |
14.4
|
E |
| 1212 |
SOLAR ALICE
IMO 9887384
|
24,621 | 2021 |
14.4
|
E |
| 1213 |
SALTSTRAUM
IMO 9854466
|
10,585 | 2020 |
14.4
|
E |
| 1214 |
GIANNA
IMO 9428360
|
49,999 | 2009 |
14.5
|
E |
| 1215 |
NGOL OKAVANGO
IMO 9827994
|
13,498 | 2019 |
14.5
|
E |
| 1216 |
SEN ARCHE
IMO 9443061
|
8,956 | 2008 |
14.6
|
E |
| 1217 |
NQ ROSA
IMO 9304318
|
8,807 | 2004 |
14.6
|
E |
| 1218 |
HARBOUR FOUNTAIN
IMO 9473107
|
16,929 | 2011 |
14.6
|
E |
| 1219 |
ORIS SYNERGY
IMO 9388211
|
13,091 | 2008 |
14.6
|
E |
| 1220 |
YM MIRANDA
IMO 9554755
|
12,933 | 2013 |
14.6
|
E |
| 1221 |
HARBOUR EXPRESS
IMO 9418822
|
20,528 | 2011 |
14.6
|
E |
| 1222 |
IRIS THERESA
IMO 9873254
|
12,602 | 2020 |
14.6
|
E |
| 1223 |
BELLIS THERESA
IMO 9192375
|
15,200 | 2000 |
14.7
|
E |
| 1224 |
ASKHOLMEN
IMO 9436381
|
16,801 | 2009 |
14.7
|
E |
| 1225 |
CHEMICAL EXPLORER
IMO 9820427
|
12,643 | 2018 |
14.7
|
E |
| 1226 |
GOLDEN DAISY
IMO 9878008
|
34,810 | 2015 |
14.8
|
E |
| 1227 |
WICKY SPIRIT
IMO 9404388
|
13,945 | 2006 |
14.9
|
E |
| 1228 |
AWH ALMA
IMO 9486166
|
17,055 | 2009 |
14.9
|
E |
| 1229 |
GRETA K
IMO 9800374
|
24,768 | 2016 |
14.9
|
E |
| 1230 |
W NORTH
IMO 9272735
|
8,501 | 2003 |
14.9
|
E |
| 1231 |
ATLANTIC TWIN
IMO 9341328
|
15,212 | 2008 |
14.9
|
E |
| 1232 |
HARBOUR FIRST
IMO 9473119
|
16,894 | 2011 |
14.9
|
E |
| 1233 |
YM SATURN
IMO 9362138
|
15,988 | 2007 |
15.0
|
E |
| 1234 |
YM JUPITER
IMO 9291597
|
15,995 | 2007 |
15.0
|
E |
| 1235 |
HARBOUR FASHION
IMO 9473080
|
16,878 | 2011 |
15.0
|
E |
| 1236 |
LIVATYA
IMO 9291444
|
8,817 | 2004 |
15.0
|
E |
| 1237 |
NEW SPIRIT
IMO 9337872
|
12,970 | 2008 |
15.0
|
E |
| 1238 |
WINTER SUN
IMO 9317028
|
9,517 | 2005 |
15.0
|
E |
| 1239 |
HELEN
IMO 9263136
|
21,183 | 2002 |
15.0
|
E |
| 1240 |
MISSISSIPPI STAR
IMO 9527623
|
13,054 | 2010 |
15.1
|
E |
| 1241 |
SONGA ORION
IMO 9831024
|
17,916 | 2020 |
15.1
|
E |
| 1242 |
TANKER BEE 11
IMO 9356646
|
8,019 | 2007 |
15.1
|
E |
| 1243 |
TINERFE
IMO 9498107
|
17,540 | 2009 |
15.1
|
E |
| 1244 |
KIRKEHOLMEN
IMO 9553402
|
17,136 | 2010 |
15.2
|
E |
| 1245 |
RIVER OAK
IMO 9438157
|
13,133 | 2007 |
15.2
|
E |
| 1246 |
KARLICA
IMO 9220354
|
12,000 | 2000 |
15.2
|
E |
| 1247 |
ROSSI A. DESGAGNES
IMO 9804435
|
14,919 | 2019 |
15.2
|
E |
| 1248 |
OWL 1
IMO 9439369
|
13,053 | 2009 |
15.3
|
E |
| 1249 |
TELLUS
IMO 9321615
|
9,181 | 2006 |
15.3
|
E |
| 1250 |
SCORPIUS
IMO 9318228
|
11,249 | 2006 |
15.3
|
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.