Most Emission-Efficient Gas 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 2024. Lower is greener. Pick a segment and size class to see the greenest vessels first.

Segment rank (2024)

#28 of 316 gas carriers

CO₂ intensity

6.2 g CO₂/dwt·nm

vs segment average (13.55)

-54% greener

Bulk Carrier Container Ship Oil Tanker Chemical Tanker Gas Carrier LNG Carrier General Cargo Vehicle Carrier Refrigerated Cargo Ro-Ro Cargo

Sort 🌱 Greenest first 🔧 Least efficient first — retrofit candidates

Size (DWT)

All sizes < 25,000 DWT 25k – 60k DWT 60k – 100k DWT 100k – 200k DWT > 200,000 DWT

Year

2025 2024

323

vessels ranked

4.53

greenest (g CO₂/t·nm)

11.21

segment median

#	Vessel	Size (DWT)	Built	Length	Main Engine	Carbon intensity — AER (g CO₂/dwt·nm)	Grade
1	ARCTIC GAS IMO 9745512	24,303	2017	160 m	STX - 6S60ME-B8	4.5	A
2	ASTERIX I IMO 9892298	93,403	2023	299 m	Hyundai - 5X72DF	4.7	A
3	ARISTIDIS I IMO 9862906	93,368	2021	299 m	Hyundai - 5X72DF	5.3	A
4	HANNIBAL IMO 9933523	58,000	2024	230 m	CSSC-MES Diesel Co Ltd - China 6G60ME-C10-LGIP	5.3	A
5	COMET IMO 9689914	54,420	2014	225 m	HHI - 6G60ME-C9.2	5.3	A
6	NILE RIVER IMO 9933779	58,666	2024	230 m	STX Heavy Industries Co Ltd - Changwon 6G60ME-C10-LGIP	5.4	A
7	ARISTARCHOS IMO 9862918	93,427	2021	299 m	Hyundai - 5X72DF	5.4	A
8	ASKLIPIOS IMO 9884021	93,352	2021	299 m	Hyundai - 5X72DF	5.4	A
9	OCEANUS AURORA IMO 9555008	58,495	2023	230 m	STX Heavy Industries Co Ltd - Changwon 6G60ME-C10-LGIP	5.5	A
10	ADAMASTOS IMO 9879698	93,566	2021	299 m	Wärtsilä - 5X72DF	5.5	A
11	AXIOS II IMO 9943853	93,736	2021	299 m	HD Hyundai Heavy Industries Co Ltd - South Korea 2 x 5X72DF-HPSCR	5.5	A
12	KAEDE IMO 9932581	59,320	2023	227 m	Hyundai - 6G60ME-C10	5.6	A
13	TESSALA IMO 9761243	94,575	2016	291 m	Wärtsilä - 2x8L50DF / 2x12V50DF	5.8	A
14	LEGISLATOR IMO 9938523	59,017	2022	227 m	Hyundai - 6G60ME-C9	5.9	A
15	CRYSTAL RIVER IMO 9780641	54,171	2017	230 m	Kawasaki - 7S60ME-C8.2	5.9	A
16	PHOENIX HARMONIA IMO 9947483	56,711	2023	230 m	Mitsui E&S DU Co Ltd 6G60ME-C10-LGIP	5.9	A
17	MERCATOR IMO 9938535	59,017	2023	227 m	Hyundai - 6G60ME-C9	6.0	A
18	CONSTELLATION IMO 9734680	54,335	2014	225 m	MAN - 6G60ME-C9	6.0	A
20	LANTANA PLANET IMO 9933444	55,153	2023	230 m	Kawasaki Heavy Industries Ltd - Japan 7S60ME-C10-LGIP	6.1	A
19	ENEOS WISDOM IMO 9935507	59,504	2022	230 m	Hyundai Heavy Industries Co. Ltd. 6G60ME-C10-LGIP-HPSCR	6.1	A
21	ATTALOS IMO 9862920	93,321	2021	299 m	Hyundai - 5X72DF	6.1	A
22	SUMIRE GAS IMO 9723681	54,243	2016	230 m	Kawasaki - 7S60ME-C8.2	6.2	A
23	CHEYENNE IMO 9706504	54,555	2015	225 m	MAN - 6G60ME-C9	6.2	A
24	PERTAMINA GAS DAHLIA IMO 9937074	58,265	2024	230 m	MAN - 6G60ME-C10	6.2	A
25	BW TUCANA IMO 9735658	54,116	2016	225 m	MAN - 6G60ME-C9	6.2	A
26	PINZA IMO 9790232	51,202	2018	230 m	Hyundai - 6G60ME-C9	6.2	A
27	AEOLIAN PEARL IMO 9754824	54,675	2016	225 m	MAN - 6G60ME-C9	6.2	A
28	BW VAR IMO 9748227	54,053	2016	225 m	MAN - 6G60ME-C9	6.3	A
29	PERTAMINA GAS CASPIA IMO 9937062	58,257	2024	230 m	STX Heavy Industries Co Ltd - Changwon 6G60ME-C10-LGIP	6.3	A
31	GAS STELLA IMO 9765562	55,001	2017	230 m	MAN - 7S60ME-C8	6.4	A
30	CLIPPER WILMA IMO 9855941	51,098	2019	230 m	Hyundai - 6G60ME-C9	6.4	A
32	GAS NOUVEAU BAUHINIA IMO 9958987	58,201	2024	230 m	CSSC-MES Diesel Co Ltd - China 6G60ME-C10-LGIP-HPSCR	6.4	A
33	GAS BARBAROSSA IMO 9903762	53,759	2021	230 m	MAN - 6G60ME-C9	6.4	A
34	BW MESSINA IMO 9735062	54,647	2017	226 m	Hyundai - 6G60ME-C9	6.5	A
35	MANIFESTO IMO 9625152	54,901	2013	225 m	Hyundai - 6S60MC - C 8.2	6.5	A
36	ARISTOS I IMO 9862891	93,448	2020	299 m	Hyundai - 5X72DF	6.5	A
37	DURHAM IMO 9889564	55,408	2021	230 m	Kawasaki Heavy Industries Ltd - Japan 7S60ME-C8.2	6.6	A
38	BW TOKYO IMO 9398307	54,936	2009	230 m	Mitsui - 7S60MC-MKVI	6.6	A
39	VIVIT FORNAX IMO 9835185	54,406	2019	228 m	Hyundai - 6G60ME-C9	6.7	A
40	SHAHRASTANI IMO 9726085	54,702	2016	225 m	MAN - 6G60ME-C9	6.7	A
41	GAZ IMPERIAL IMO 9795919	54,304	2018	230 m	Hudong Heavy Machinery - 6G60ME-C9	6.7	A
42	NS DREAM IMO 9800506	54,052	2019	230 m	MAN - 7S60ME-C8	6.8	A
43	VIVIT THUBAN IMO 9840867	50,703	2019	230 m	Hyundai - 6G60ME-C9	6.8	A
44	HAMPSHIRE IMO 9377781	53,293	2007	226 m	Kawasaki - 5S70MC	6.8	A
45	PYXIS PIONEER IMO 9792747	53,928	2019	230 m	Kawasaki - 7S60ME-C8.2	6.8	A
46	HELLAS POSEIDON IMO 9721140	54,361	2015	225 m	MAN - 6G60ME-C9	6.8	A
47	SARV SHAKTI IMO 9350599	54,783	2008	226 m	Doosan - 6S60MC-C	6.8	A
48	OUGARTA IMO 9761267	94,575	2017	291 m	Wärtsilä - 2x8L50DF, 12V50DF	6.9	A
50	CONCORDE IMO 9734678	53,999	2015	225 m	MAN - 6G60ME-C9	6.9	A
49	AXIS RIVER IMO 9949704	56,503	2023	230 m	MAN-B&W 6G60ME-C10-LGIP	6.9	A

Page 1 of 7 — 316 vessels

Engine intelligence

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 2024 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.

Emission-friendly engine ranking

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.