MAN Diesel & Turbo has secured a contract from Greece-based Alpha Tankers and Freighters International to supply MAN 51/60DF dual-fuel engines for its two LNG carriers (LNGCs).

Under the deal, which also includes an option for further vessels and engines, each vessel will be powered by two 9L51/60DF and two 8L51/60DF engines having a total combined output of 34MW.

All engines are IMO Tier II-compliant in diesel mode and will have lower exhaust-gas emissions in gas mode than required by Tier III standards, while fuel-sharing mode will be applied to each unit.

Both 160,000m³ dual-fuel diesel electrical (DFDE)-driven LNG vessels will be built at South Korea’s STX Offshore & Shipping and are scheduled to be delivered in 2014 and 2015.

MAN Diesel & Turbo’s Augsburg plant in Germany will build the engines, which are expected to be delivered in the fourth quarter of 2013.

According to the company, the order marks the first LNGC new-build with fuel-sharing capability, which was developed for its MAN B&W ME-GI type, a gas-injection two-stroke dual-fuel diesel engine.

The dual-fuel engines in the vessel can burn both gaseous and liquid fuels simultaneously in order to optimise fuel flexibility in fuel-sharing mode, which is useful during ballast voyages where the volume of generated, natural boil-off gas is lower than on a laden voyage.