Special Feature : OPEN SEA, July 2012, No.30

On June 29, the hybrid car carrier Emerald Ace was completed. The vessel uses elemental technologies based on MOL’s ISHIN-I concept for the next-generation car carrier, which was announced in September 2009. ISHIN-I is aimed at promoting innovative approaches to reducing CO2 emissions using technically practical technologies. This section introduces the ideas behind the hybrid car carrier that uses renewable energy as one of its elemental technologies, and explains how it works.

Hybrid car carrier Emerald Ace

Hybrid power generation system to realize zero emissions while on berth

The Emerald Ace is equipped with a hybrid power supply system combined with a solar power generation system and lithium-ion batteries. Conventional vessels use diesel-powered generators to produce electricity while they are on berth. But on the Emerald Ace, the solar power generation system generates electricity while the ship is under way and stores it in the lithium-ion batteries. The diesel-powered generator is completely shut down when the ship is on berth, and the batteries provide all the electricity the ship needs, resulting in zero emissions at the pier.

Takahiro Hayakawa
Technical Division, Design Group

Team Senpaku ISHIN
(Hayakawa is fourth from the left)

“The completion of the world’s first hybrid car carrier demonstrates both MOL’s commitment to protecting the environment and its advanced technological capabilities. These technologies were developed for use on land, so we faced some major challenges in adapting them to the unique needs of an ocean-going ship. However, I am very happy that we succeeded in completing the vessel on schedule, thanks to the close cooperation of the equipment manufacturers and the shipbuilder.”


Solar power panel The panels have glass on both sides and were designed for optimum resistance to climatic conditions such as salt air and wind. Output of the solar panel is 160kW (210W/panel x 768 panels = 1,079m²) This is the world’s largest solar panel system installed on a ship.	Lithium-ion batteries Lithium-ion batteries, which have superior energy density, store electricity produced by the solar panels, while taking up minimal onboard space. The battery system has an in limited onboard space. Electric energy is 2.2MWh. The high-performance power management system controls this massive amount energy safely and efficiently.