Ultra long stroke MAN, B&W green engines

The G-type is an ultra long stroke engine and represents the biggest development 

For VLCCs, it is estimated that the application of a 7G80ME-C will prompt an overall efficiency increase of 4-5%, compared with a 7S80ME-C9 or an alternative engine design with the same engine speed.

The green ultra long stroke G-type engine delivers lower rpm with

significant fuel and CO2 reductions of up to 7% as part of a propulsion package.

The G-type is an ultra-long-stroke engine and represents the biggest development within our engine portfolio since the successful introduction of the ME electronic engine within the last decade.”

Tankers and bulk carriers have traditionally used MAN B&W S-type engines with their long stroke and low engine speed as prime-movers, while larger container vessels have tended to use the shorter-stroke K-type with its higher engine speed.

savings compared in %:

Propeller  -    3.6

Engine      -   1.0

Total         -  4.6

MAN Diesel & Turbo has also thoroughly evaluated the possibility of using even larger propellers and thereby engines with even lower speeds for the propulsion of tankers and bulk carriers.

Engine Data             S80ME-C9      G80ME-C9
Power (kW/cyl.)            4510                  4450
Engine speed (rpm)        78                    68
Stroke (mm)                 3450                  3720
MEP (bar)                        20                   21
Mean Piston Speed      8.97                8.43
Length, 7 cyl. (mm)     12034             12500
Dry mass, 7 cyl. (ton)    910                 960
SFOC, L, (g/kWh)          168                167

Following efficiency :

1.trend in the market
2.more compatible with propellers with larger diameters than current designs
3. facilitate higher efficiencies following adaptation of the aft-hull design to accommodate a larger propeller
4.savings of some 4-7 percent
5.reduction in CO2 emissions.