Russian gas resources located in the sub-zero Arctic are propelling the need for a new generation of ice-breaking LNG carriers
Vast Russian natural gas resources located above the frigid Arctic circle have spawned a new generation of robust, ice-breaking LNG carriers designed with reinforced hulls, enhanced podded propulsion and vibration-resistant cargo containment technology. A steel cutting ceremony was held in April at Russia’s Zvezda Shipbuilding Complex for one of the latest of these LNG carriers that will operate in temperatures of as low as -52°C by mid-decade.
Like all 15 LNG carriers being built by Zvezda in the series, the ARC7 ice class LNG carrier is being built for a long-term, time-charter for Novatek’s Arctic LNG 2 project. Designed by Zvezda with technology partner Samsung Heavy Industries, each vessel will have an overall length of 300 m, beam of 48.8 m, depth of 26 m, with a capacity of 172,600 m3 using GTT’s Mark III membrane containment technology. This is the second of 14 to be built for Smart LNG, a joint venture between Sovcomflot and Novatek. The lead vessel of the series is owned by Sovcomflot.
This is an historic project for Russia, since these next generation dual-fuel vessels are the first LNG carriers built in the country. Featuring impressive ice-breaking capabilities, the LNG carriers’ reinforced hulls will allow transiting stern first in ice up to 2.1 m thick and 1.5 m thick moving forward. Additionally, these new LNG carriers will underpin local Russian maritime technology knowledge and development.
All will have enhanced manoeuvrability supplied by three 15-MW General Electric Sapfir azimuth podded thrusters, produced locally in Bolshoy Kamen at the Sapphire Steerable Thrusters Plant, a joint venture of Rosneft and GE.
Set for delivery between March 2023 and December 2025, this series of Arctic LNG carriers is being financed by VEB.RF.
100% fleet utilisation
With long-term charter agreements in place with Yamal LNG, Gazprom and Equinor, Dynagas has its own unique fleet of ice class notation 1 (or equivalent) LNG carriers that operate in sub-zero and ice-infested waters. Its LNG carrier Ob River was the first to carry an LNG cargo on the Northern Sea Route in 2012, proving the viability of such operations.
Sister vessels Ob River, Clean Energy, and Amur River were all built by South Korea’s Hyundai Heavy Industries between 2007 and 2008. Each vessel has an overall length of 288.2 m, beam of 44.2 m, draught of 12.4 m, with a capacity of 150,000 m3 and steam turbine propulsion.
The company’s other vessels, Arctic Aurora, Lena River and Yenisei River, were all built between 2013 and 2014 by HHI. Each vessel has a length overall of 228.1 m, beam of 44.2 m, draught of 12.5 m, with tri-fuel, diesel-electric (TFDE) propulsion and a capacity of 155,000 m3.
Dynagas Holdings’ limited partnership, Dynagas LNG Partners LP, formed to own and operate its fleet, reported 100% fleet utilisation with an average time charter equivalent of US$61,134 per day during Q4 2020. It inked a new charter deal with Equinor for the 2013-built, Ice Class 1A FS, fully winterised Arctic Aurora that will keep the vessel employed into 2023, generating about US$21.5M for Dynagas LNG.
Gas carrier design for multi-fuel future
With the LNG-fuelled fleet growing, new ice-class LNG bunkering vessels are also being conceived. Leaning into the multi-fuel future, Danish naval architectural and marine engineering firm Knud E Hansen has unveiled a flexible liquefied gas and bunkering vessel design that can accommodate LNG and zero-emissions fuels, such as compressed and liquefied hydrogen.
Knud E Hansen senior mechanical engineer Kim Nørby Christensen explained the idea behind the X-gas Project: “It will be able to transport almost any gas (liquid or compressed) for future fuels. When we mention hydrogen, we see it as the link in the power-to-x technology, as hydrogen plants are planned in many countries, but there must be a link like the X-gas to connect production plants and consumers.” This covers the carriage of CO2 and ammonia, too.
Knud E Hansen’s X-gas Project is a series of medium-capacity liquefied gas supply and bunkering vessels, the largest of which would be a ‘flagship’ 126.5-m vessel with a total cargo capacity of 9,000 m3 for LNG, split between two IMO Type C tanks. The vessel will have a beam of 20.5 m, design draught of 5.25 m and deadweight of 4,775 tonnes.
The tank system, the top side equipment and the associated ship particulars will change depending on the application, “but we target almost all the gasses that the operator wants to carry, and we will take care of the necessary ship particulars for the request,” said Mr Christensen. He noted that with the variety of fuels under consideration for the future, and with the large differences in mass density and energy density, “we consider a brand like X-gas to be the right way to promote tankers under a common ‘umbrella’, here represented by the LNG ‘flagship’.”
Built with the notation Ice Class 1A, the liquefied gas transport and bunkering vessel would be capable of navigating in difficult ice conditions, with the assistance of icebreakers when necessary under DNV rules, or the equivalent Finnish-Swedish Ice Class 1A notation. Ice Class 1A vessels have thicker hull plating and ice-strengthened framing.
“[The X-gas Project] will be able to transport almost any gas, liquid or compressed, for future fuels”
Knud E Hansen says the X-gas platform can be built with different tank capacities and containment systems, including membrane tanks.
Notable is the vessel’s low-profile and forward deck house, which will enable it to safely approach and pull alongside cruise ships with low-hanging lifeboats. Additionally, this minimises the need for ballast during cargo transfer, lowering operational costs. Lastly, the forward deck house allows for larger cargo tanks without impeding bridge visibility.
For improved manoeuvring and safety, the design features two propulsion thrusters aft and two bow thrusters and an autodocking system for alongside mooring.
Propulsion for the vessel will be supplied by four-stroke, dual-fuel diesel-electric engines, and an energy storage system (ESS) with a lithium-ion battery bank for engine load optimisation. This will allow the vessel to operate on batteries during low load conditions – avoiding methane slip when operating on LNG. The batteries will provide all of the power required during cargo transfer or bunkering operations, resulting in no emissions or exhaust – especially important when refuelling passenger vessels. Service speed will be 13 knots.
Other energy efficiency features incorporated in the design are the use of boil-off gas in the dual-fuel engines, with the ability to store any surplus energy in the batteries. Waste heat from the engine cooling water is converted to electric and thermal power through a number of Organic Rankine Cycle waste heat units.
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