The Features Of The Modern Japanese LNG Carriers

Prior to the Fukushima nuclear accident in March 2011, the nuclear power reactors generated almost 30% from the electricity production. After the Fukushima nuclear accident, the nuclear reactors were shut down for inspection and upgrades. As a result, the demand for natural gas in the power generation in Japan increased considerably.
To fill the gap left by the closure of nuclear plants, Japan`s top utility companies invested in LNG projects in Australia, US and elsewhere and concluded long-term LNG purchase agreements on FOB terms with the suppliers. To transport the LNG to Japan, the Japan`s top utility companies ordered a new generation of LNG carriers to the Japanese shipbuilders – Mitsubishi Heavy Industries, Kawasaki Heavy Industries and Japan Marine United Corporation.
In the meantime, a part of the nuclear power plants` reactors have received the permission to reopen and restart the production of nuclear energy. Japan`s government plans to increase the share of the nuclear power in the electricity generation to 20% by 2030, not only by restarting the existing nuclear reactors but also by building new reactors. This will gradually reduce the demand for natural gas in the power generation and a part of the LNG cargoes purchased by the Japan`s utility companies under long-term agreements will be re-sold on a spot or short-term basis in other countries. The diverted cargoes will be transported to destination by the modern Japanese LNG carriers built by Mitsubishi Heavy Industries, Kawasaki Heavy Industries and Japan Marine United Corporation.

The Features Of Sayaendo LNG Carriers

Sayaendo class refers to a type of LNG carrier with a transport capacity of 155,000 cbm designed and built by Mitsubishi Heavy Industries (MHI) between 2011 and 2018 for the transport of LNG from the Australian LNG terminals to Japan.
Sayaendo LNG carriers have four spherical Moss-type tanks (Spherical IMO Type B Tanks) protected by a peapod-shaped continuous steel cover that is integrated with the hull.
Another feature of Sayaendo LNG carriers is the steel hull structure which is about 5% lighter in weight than that of the LNG carriers built before 2010.
Sayaendo LNG carriers are powered by MHI`s Ultra Steam Turbine plant which utilizes the steam reheat technology. The Ultra Steam Turbine plant consists of a high pressure turbine, an intermediate pressure turbine, a low pressure turbine and a reheat boiler. It utilizes a reheat cycle whereby the exhaust steam from the high pressure turbine is returned to and re-heated in the boiler and then sent to the intermediate pressure turbine.
The steam reheat technology improves the thermal efficiency of the steam turbine propulsion system with approximately 15% compared to the conventional steam turbine plants.
The continuous steel cover over the cargo tanks that reduces the wind pressure from the front, the lighter hull structure and the steam reheat technology contribute to a 20% reduction in the fuel consumption and to a proportional CO₂ emission reduction compared to the conventional steam turbine LNG carriers built before 2010.
The use of additional energy saving devices improves the propulsion performance and reduces CO₂ emission per unit load (in actual operation) by up to approximately 25% in comparison with the conventional steam turbine LNG carriers with a 147,000 cbm transport capacity previously built by Mitsubishi Heavy Industries.
The cargo tanks` insulation panels supplied by Ti Group, a subsidiary company of Wilhelmsen Technical Solutions, enable Sayaendo LNG carriers to have an LNG boil-off rate of just 0.08%.
There are eight Sayaendo LNG carriers in service:
- "LNG Venus" delivered in 2014. It is co-owned by Mitsui O.S.K. Lines and Osaka Gas International Transport.
- "Esshu Maru" delivered in 2014. It is co-owned by Mitsui O.S.K. Lines and Osaka Gas International Transport.
- "Seishu Maru" delivered in 2014. It is co-owned by Chubu Electric, Mitsubishi and NYK Line.
- "LNG Jurojin" delivered in 2015. It is co-owned by Mitsui O.S.K. Lines and Kansai Electric Power Co., Inc.
- "LNG Mars" delivered in 2016. It is co-owned by Mitsui O.S.K. Lines and Osaka Gas International Transport.
- "LNG Saturn" delivered in 2016. It is co-owned by Mitsui O.S.K. Lines and Osaka Gas International Transport.
- "Oceanic Breeze" delivered in 2018. It is co-owned by K Line and INPEX Corporation.
- "Pacific Mimosa" delivered in 2018. It is owned by NYK Line.

The Features Of Sayaringo STaGE LNG Carriers

Sayaringo STaGE class refers to a type of LNG carrier designed in 2014 by Mitsubishi Heavy Industries (MHI) for the transport of LNG from the US Gulf LNG terminals to Japan through the Panama Canal.
Like the Sayaendo LNG carriers, Sayaringo STaGE LNG carriers feature a continuous steel cover over the cargo tanks, but unlike Sayaendo LNG carriers where the cargo tanks have a spherical shape, in the case of Sayaringo STaGE LNG carriers, the cargo tanks have the shape of apples, with the upper half larger than the lower half. This form of tanks was designed to transport larger volumes of LNG than Sayaendo LNG carriers, without increasing the ship`s width beyond the maximum acceptable for the transit of the Panama Canal (48.94 meters). As a result, the maximum transport capacity of Sayaringo STaGE LNG carriers is 180,000 cbm, higher than that of Sayaendo class which is 155,000 cbm.
The cargo tanks` insulation panels supplied by Ti Group, a subsidiary company of Wilhelmsen Technical Solutions, enable Sayaringo STaGE LNG carriers to have an LNG boil-off rate of just 0.08%.
Sayaringo STaGE LNG carriers have a twin-shaft twin-rudder hybrid propulsion system called "STaGE", an abbreviation for "Steam Turbine and Gas Engine" which consists of an ultra steam turbine plant on the port side, a dual-fuel diesel engine and a propulsion electric motor on the starboard side. The STaGE plant enables Sayaringo STaGE LNG carriers to sail at a speed of 19.5 knots.
STaGE plant is more efficient than the Ultra Steam Turbine plant of Sayaendo LNG carriers. It uses a waste heat recovery system whereby the waste heat from the dual-fuel diesel engine is recovered to heat the boiler feedwater. The heated feedwater flows to the boiler to generate steam to be used to drive the main turbine. This technology enables the STaGE plant to emit about 20% less CO₂ than the conventional steam turbine plants. In addition, the enlarged lightweight hull form and the continuous cover over the cargo tanks enable the Sayaringo STaGE LNG carriers to reduce CO₂ emissions per cargo unit with 40% compared to the conventional steam turbine LNG carriers with a 147,000 cbm cargo capacity.
The ability to burn gas in all operation modes, including at LNG terminals, enables the Sayaringo STaGE LNG carriers to comply with IMO Tier III NOx emission limits in the North American and US Carribean Sea Emission Control Areas.
There are eight Sayaringo STaGE LNG carriers in service:
- "Diamond Gas Orchid" with an LNG transport capacity of 165,000 cbm. It was delivered in 2018 by Mitsubishi Heavy Industries. It is owned by NYK Line.
- "Diamond Gas Rose" with an LNG transport capacity of 165,000 cbm. It was delivered in 2018 by Mitsubishi Heavy Industries. It is owned by NYK Line.
- "LNG Juno" with an LNG transport capacity of 180,000 cbm. It was delivered in 2018 by Mitsubishi Heavy Industries. It is owned by Mitsui O.S.K. Lines.
- "Diamond Gas Sakura" with an LNG transport capacity of 165,000 cbm. It was delivered in 2019 by Mitsubishi Heavy Industries. It is owned by NYK Line.
- "Bushu Maru" with an LNG transport capacity of 180,000 cbm. It was delivered in 2019 by Mitsubishi Heavy Industries. It is co-owned by NYK Line and JERA.
- "Marvel Crane" with an LNG transport capacity of 177,000 cbm. It was delivered in 2019 by Mitsubishi Heavy Industries. It is co-owned by NYK Line and Mitsui & Co., Ltd.
- "Marvel Heron" with an LNG transport capacity of 177,000 cbm. It was delivered in 2019 by Mitsubishi Heavy Industries. It is co-owned by NYK Line and Mitsui & Co., Ltd.
- "Nohshu Maru" with an LNG transport capacity of 180,000 cbm. It was delivered in 2019 by Mitsubishi Heavy Industries. It is co-owned by NYK Line and JERA.

The Features Of Modern LNG Carriers Built By Kawasaki Heavy Industries

Between 2011 and 2019, Kawasaki Heavy Industries built eleven LNG carriers: five LNG carriers with Kawasaki URA-400 Plant and six LNG carriers with dual-fuel diesel electric propulsion system.
The LNG carriers with Kawasaki URA-400 Plant are:
- "Energy Horizon" with an LNG transport capacity of 177,000 cbm. It was delivered in 2011. It is owned and operated by NYK Line.
- "Grace Dahlia" with an LNG transport capacity of 177,427 cbm. It was delivered in 2013. It is owned and operated by NYK Line.
- "LNG Fukurokuju" with an LNG transport capacity of 165,134 cbm. It was delivered in 2016. It is co-owned by Mitsui O.S.K. Lines and Kansai Electric Power Co., Inc.
- "Bishu Maru" with an LNG transport capacity of 164,700 cbm. It was delivered in 2017. It is owned by Trans Pacific Shipping.
- "Enshu Maru" with an LNG transport capacity of 164,700 cbm. It was delivered in 2018. It is owned and operated by K Line.

These LNG carriers have four spherical Moss-type tanks (Spherical IMO Type B Tanks) insulated with polyurethane foam Kawasaki Panel System that keeps the LNG boil-off rate at 0.08% per day.
Kawasaki URA-400 Plant (Kawasaki Advanced Reheat Turbine Plant) is a reheating-type steam turbine propulsion plant. It consists of a high pressure turbine, an intermediate pressure turbine, a low pressure turbine and a reheat boiler. It utilizes a reheat cycle whereby the exhaust steam from the high pressure turbine is returned to and re-heated in the boiler and then sent to the intermediate pressure turbine. The steam reheat technology improves the thermal efficiency of the steam turbine propulsion system with approximately 15% compared to the conventional steam turbine propulsion plants.
Kawasaki URA-400 Plant enables the LNG carriers to sail at a speed of 19.5 knots.

DFDE LNG Carriers built by Kawasaki Heavy Industries are:
- "LNG Sakura" with an LNG transport capacity of 177,000 cbm. It was delivered in 2018. It is co-owned by NYK Line and Kansai Electric Power Co., Inc.
- "Marvel Eagle" with an LNG transport capacity of 155,000 cbm. It was delivered in 2018. It is owned by Mitsui O.S.K. Lines.
- "Pacific Breeze" with an LNG transport capacity of 182,000 cbm. It was delivered in 2018. It is owned by K Line.
- "Marvel Pelican" with an LNG transport capacity of 155,985 cbm. It was delivered in 2019. It is owned by Mitsui O.S.K. Lines.
- "Shinshu Maru" with an LNG transport capacity of 177,000 cbm. It was delivered in 2019. It is owned by Mitsui O.S.K. Lines.
- "Sohshu Maru" with an LNG transport capacity of 177,300 cbm. It was delivered in 2019. It is owned by Mitsui O.S.K. Lines and JERA.

These LNG carriers have four spherical Moss-type tanks (Spherical IMO Type-B Tanks) insulated with polyurethane foam Kawasaki Panel System that keeps the LNG boil-off rate at 0.08% per day.

The Features Of Modern LNG Carriers Built By Japan Marine United Corporation

Between 2018 and 2019, Japan Marine United Corporation built four LNG carriers:
- "Energy Liberty" delivered in 2018. It is owned by Mistui O.S.K. Lines and Tokyo Gas Co., Ltd.
- "Energy Innovator" delivered in 2019. It is owned by Mistui O.S.K. Lines and Tokyo Gas Co., Ltd.
- "Energy Universe" delivered in 2019. It is owned by Mistui O.S.K. Lines and Tokyo Gas Co., Ltd.
- "Energy Glory" delivered in 2019. It is owned by NYK Line and Tokyo Gas Co., Ltd.

These ships have the same features:
- The cargo tanks designed by IHI Corporation are self-supporting prismatic IMO type B (SPB) tanks. They have a volumetric capacity of 165,000 cbm.
- The propulsion system is a tri-fuel diesel electric engine with Selective Catalytic Reduction technology to comply with NOx Tier III emission limits in the North American and US Carribean Sea Emission Control Areas.

by Vlad Cioarec, International Trade Consultant

This article has been published in Commoditylaw`s Gas Trade Review Edition No. 4.