Caterpillar Marine Power Systems is developing the MaK M 46 DF, a new marine dual-fuel engine platform for the commercial marine industry. The M 46 DF dual-fuel engine boasts a power rating of 900 kW (1200 hp) per cylinder at 500 and 514 rpm in diesel and gas modes, and is available in an inline or vee configuration. The engine is currently being tested at Caterpillar’s medium-speed engine facility in Rostock, Germany. First engine deliveries are foreseen for 2014. Able to alternate from gas to diesel mode during operation, the M 46 DF offers the flexibility to operate vessels in all geographical areas, whether the fuel in use is LNG (liquefied natural gas), marine diesel oil, or heavy fuel oil. In gas mode, the M 46 DF is said to feature industry-leading fuel consumption and will comply with IMO III as well as EPA Tier 4 regulations. The engine has been designed to allow retrofitting of current M 43 C engines. With a bore of 460 mm (18.1 in) and stroke of 610 mm (24.0 in), the engine was designed for electric drive as well as mechanical propulsion systems.