Tsuji Heavy Industries has started construction of the first of the two LNG-powered cargo vessels at its Jiangsu shipyard in China.

The 5,000dwt vessels, known as Environship, are claimed to be the world’s first LNG (liquefied natural gas)-powered cargo ships, which are being built for Norwegian transportation firm Nor Lines.

Rolls-Royce won the design contract in October 2011, and will also offer integrated power and propulsion systems for the vessels.

The contract also included an option to build an additional two ships of the same design.

Both vessels will be built to the Rolls-Royce NVC 405 design specification at the Tsuji’s Jiangsu shipyard.

The two new cargo vessels are scheduled to enter service from October 2013, operating along the West Coast of Norway.

Rolls-Royce’s design incorporates a striking wave-piercing bow, gas-powered engines and propulsion system and improvments to the overall performance of the vessel to increase fuel efficiency by up to 18%.

The company aims to eliminate SOx emissions, reduce CO2 emissions by more than 40% and cut NOx emissions by about 90%, compared with similar conventional ships.

The Environship concept will also offer reductions in fuel burn and emissions, as well as improved performance at sea.

Rolls-Royce plans to use the concept to develop a wide range of other efficient ship designs, including passenger ferries, chemical tankers, gas tankers, bulk carriers and superyachts.

Particulate emissions from the ship will be within the limits of International Maritime Organisation (IMO) Tier III environmental legislation that are scheduled to come into force in 2016..