Diverse vessel needs drive bunker technologies

From battery-powered bunker vessels to on-board cranes for gas tanks, there is no shortage of ingenuity in the technologies being used to deliver LNG fuel to ships

“Bunkering infrastructure is expanding, encouraging operators to adopt LNG,” says SEA/LNG chairman Peter Keller as he summarises a period of rapid growth for gas fuel in 2018. “From limited availability at select ports, LNG bunkering has grown to encompass 24 out of the world’s top 25 ports and all but one of the top 10 bunker ports globally.”

The trend has been mirrored by LNG bunker vessels (LBV), where the range and flexibility of refuelling options has been extended. The one bunker vessel in service at the beginning of 2017 was joined by a further eight by the end of 2018. It is a phenomenon that is set to continue, with SEA/LNG anticipating around 30 more such vessels being delivered over the next five years. According to DNV GL’s Alternative Fuel Insight platform there are 13 bunker vessels in operation today, a further 17 decided upon (including those already ordered from shipyards or chartered out) and another six under discussion.

As some of those projects enter the construction phase, Singapore’s rival shipyard groups Keppel Offshore & Marine and Sembcorp Marine are emerging as two of the big beneficiaries.

At its Keppel Singmarine yard in Nantong, Keppel is already building the first LBV destined to serve Singapore – a 7,500 m3 vessel for the FueLNG joint venture (between Keppel and Shell) that has won a concession at the world’s biggest bunker port. That vessel will be completed in Q3 2020. More recently, in December, Russian oil tanker company Shturman Koshelev commissioned Keppel to build an LBV with ice-class 4 notation and a cargo capacity of 5,800 m3, due for delivery in Q4 2020. It will be chartered to Gazprom Neft for operation in the Baltic Sea.

Buoyed by its early experience with bunkering vessels, Keppel is now looking to strengthen its expertise by co-operating on design and research with DNV GL. A framework agreement between the class society and Keppel Marine and Deepwater Technology covers potential newbuilding projects including LBVs, small-scale LNG carriers and floating storage regasification units (FSRUs), as well as LNG-related assets employing battery and hybrid technologies.

“We have a strong track record in delivering LNG solutions that includes the first FLNG conversion as well as LNG-fuelled vessels,” says Keppel managing director for gas and specialised vessels Abu Bakar Mohd Nor. He explains that the agreement will enable Keppel to develop a suite of LNG-related vessels to meet the needs of the market as the adoption of LNG as marine fuel increases.

As the first delivery in the agreement, DNV GL will issue Approvals in Principle for two LBV designs from KMDTech. Both are designed to carry up to 7,500 m3 of LNG in Type C-tanks, with one featuring a hybrid propulsion configuration with batteries. An optimised deck arrangement for the modular LNG gas supply, filling and safety systems increases the cargo capacity and efficiency of the vessels. The vessels will have a class notation for bunkering which enables the provision of LNG bunkering services if required. They are equipped with engines that can run on both diesel and LNG.

While Keppel takes the honour of building the first LBV for Singapore, Sembcorp Marine will build another to serve the port that will become Asia’s largest such vessel. Mitsui OSK Lines subsidiary Indah Singa Maritime contracted Sembcorp Marine to build the 12,000-m3 vessel in February. When completed in early 2021, the vessel will go on long-term charter to Singapore state-owned Pavilion Gas for deployment in Singapore.

To be constructed at Sembcorp Marine Tuas Boulevard Yard, the vessel will be 112 m long and 22 m wide with two GTT Mark III Flex membrane tanks. The vessel, which will have dual-fuel engines running on LNG or marine diesel oil, will be managed by Sinanju Tankers, a major bunker barge company.

“The Mark III Flex membrane tanks weigh less and occupy less ship space, allowing the vessel to carry more cargo and consume less fuel during transportation”

This will be the first LBV built by Sembcorp Marine, which will also fabricate the vessel’s membrane tanks under a licensing agreement with LNG containment specialist GTT. Mark III Flex membrane tanks have a lower internal pressure, temperature and boil-off rate than IMO Type-C tanks. This translates into greater tank durability, safer fuel transfer operations and reduced cargo loss through evaporation. The Mark III Flex membrane tanks also weigh less and occupy less ship space, allowing the vessel to carry more cargo and consume less fuel during transportation.

The 112 m, 12,000 m3 capacity LBV for MOL and Pavilion Gas will be the biggest in Asia

“This project marries Sembcorp Marine’s ship design and construction expertise with GTT’s industry-leading membrane tank system,” says Sembcorp Marine president and chief executive Wong Weng Sun. “We are confident the outcome will be a sophisticated newbuilding that not only delivers optimal technical performance, but also helps MOL and Pavilion Energy contribute to the expected standard of LNG bunkering operations in Singapore.”

Coastal bunkering

Increasing demand for LNG bunkering in South Korea has led the country to launch a development project for coastal ships with customised bunkering systems. The project aims to develop and validate bunkering facilities along the coast.

South Korean LNG engineering, procurement and construction company Trans Gas Solution has received approval in principle from Korean Register for a 500-m3 bunker barge design that will be part of the new coastal bunkering system. The LNG bunkering barge concept, Kolt-05B, is a 48.5-m vessel with an IMO Type C pressurised fuel tank with a storage capacity of 500 m3, including a low-pressure LNG fuel gas supply system CryoPac-L. The barge will have a bunkering arm to assist in fuelling vessels at a flowrate of 200 m3/h, and the ability to handle return gases during bunkering operations.

Funding for the LNG bunker barge concept is through a government-backed project supported by South Korea’s Minister of Maritime Affairs & Fisheries and organised by the Korea Research Institute of Ships & Ocean Engineering (KRISO). Following construction, testing and commissioning in the first half of 2021, the LNG bunkering barge system is expected to operate from 2022.

The wider coastal project brings together South Korean Government and industry. KRISO is joined in the project by steel-maker POSCO, shipbuilder, offshore and industrial construction company EK Heavy Industries, pressure vessel manufacturer Mytec and LNG fuelling station developer Valmax. Trans Gas Solution will oversee the development of the control system of the vessel, including the cargo-handling system, which covers the basic and detail design of the vessel.

The coastal project may be providing the impetus for the deployment of bunker ships in South Korea, but other projects are aiming to develop some of the technologies needed both for the country’s fledgling bunker vessel market and for its well-established gas carrier business. Shipbuilder Daewoo Shipbuilding & Marine Engineering has struck a partnership with Inha University to open a new marine and offshore research institute. There, Daewoo aims to study insulation systems and processing systems for cryogenic cargos applied to LNG carriers. The collaboration with the university is expected to continue until 2023.

“As the demand for environmentally friendly energy is increasing, so is the need for cryogenic technology development,” says Daewoo Shipbuilding & Marine Engineering director Lee Seong-keun.

LNG as a fuel might be taking off on Korea’s coast, but the English Channel will have to wait a little longer for its first gas-fuelled ship. Brittany Ferries’ 42,400-gt ropax vessel Honfleur was due to be delivered from German shipbuilder Flensburger Schiffbau-Gesellschaft (FSG) in June. It will now arrive later this year – finer details have yet to be decided – after the yard was hit by financial penalties following an earlier late delivery.

An unusual crane-driven tank configuration on Brittany Ferries' ropax Honfleur

At least the company’s bunkering infrastructure will be ready. With no permanent bunkering along the busy Ouistreham-Portsmouth route, Brittany Ferries has opted for a truck-based fuelling programme at Ouistreham that deploys an innovative combination of onboard vehicles and cranes. Lorries with ISO tanks will be driven directly onto the 187.4 m vessel, with the tanks hoisted into position in frames next to a fixed storage tank with a maximum capacity of 350 m3 at the rear of the superstructure. Once empty, the tank containers will be offloaded during the next call at Ouistreham and replaced by filled units.

Honfleur will provide capacity for 1,680 passengers and up to 550 cars and 64 trailers – or an all-freight roro payload of 130 trailers. As well as being the first vessel to bunker with onboard cranes, it will be the first Brittany Ferries vessel powered by diesel-electric propulsion. Four Wärtsilä dual-fuel engines with a total output of 29,700 kW will drive electric generators and propulsion motors for two fixed-pitch propellers with flap rudders. Manoeuvring capability is enhanced with two 2,000 kW thrusters at the bow and one at the stern.

“Honfleur will set a new standard for ferries operating on the Channel,” says Brittany Ferries CEO Christophe Mathieu. “It is important that we invest in new technologies and new vessels that respect the environment in which we operate.”

More new vessels and technologies – and more dedicated bunkering infrastructure – are on the way for Brittany Ferries’ long-haul routes. Starting in 2021 and adding one vessel a year until 2023, the company will charter three of the E-Flexer newbuilds constructed for Stena RoRo at AVIC Weihai shipyard in China, of which at least two will be LNG-fuelled.

As Mr Mathieu comments, the charters demonstrate the company’s commitment to LNG as a fuel, as well as its faith in growing traffic on its UK routes if or when the country leaves the European Union. The three 42,200-gt ships will be among the biggest in Brittany Ferries’ fleet. Each will be 215 m long with 3,000 lane metres for freight vehicles, and capacity for around 1,000 passengers in 340 cabins.

The company has already signed a bunkering agreement for one of the vessels; Spanish energy company Repsol will provide the long-term supply of LNG and shoreside infrastructure to Salamanca, scheduled to enter service in 2022. Repsol will install a fixed, quayside LNG storage and supply system in one of Brittany Ferries’ two Spanish ports, Santander or Bilbao. Repsol will then supply LNG bunker fuel during the ship’s regular visits on routes linking Portsmouth and northern Spain. A final decision on the location of the terminal will be made later this year.

“As the demand for environmentally friendly energy is increasing, so is the need for cryogenic technology development”

The deal for the construction of Honfleur was the first project to be financed under the €750M (US$853M) Green Shipping Guarantee programme implemented in 2016 by the European Investment Bank, the EU’s lending institution, as a means of promoting low-carbon investments. Innovative elements of the Honfleur design and engineering have also received public funding support through the Investissements d’Avenir (Investments for the Future) scheme, overseen by the French Agency for Environment & Energy Management (ADEME).

But public funding does not always guarantee the success of a project. Swedish shipowner Stena Line will not progress with its first dual-fuel retrofit despite receiving funding from the German government.

The project to convert the 38,000 gt ropax ferry Mecklenburg-Vorpommern for LNG received a grant from the German Ministry of Transport and Digital Infrastructure in March. But Stena Line decided not to go ahead, citing discussions around “budget, technical challenges and both operational and financial risk”.

Stena Line trade director Germany Ron Gerlach explains that the company was “by no means ruling out gas as an alternative fuel for our vessels”. As mentioned above, the company has ordered the E-Flexer series of ropax vessels from Avic International shipyard in China that will be LNG-ready, with the final ship expected to operate on gas from its delivery in 2021.

“We will stay open with regard to technologies at hand in order to allow us full flexibility in our European route network,” says Mr Gerlach. “We will also continue to focus our efforts on other projects such as looking at expanding our battery project on Stena Jutlandica to further vessels and to extend our onshore power supply solutions to include more of our ports.”

At 22 years’ old, the Mecklenburg-Vorpommern would have been one of the oldest vessels to be retrofitted for LNG. The age of a vessel can affect the viability of a conversion by limiting payback time and because of the constraints of installed engine technology.

Stena Line is familiar with challenging retrofits, having converted four Wärtsilä four-stroke engines for methanol fuel on board the then 14-year-old cruise ferry Stena Germanica from 2015.

Ambitious ports

While Brittany Ferries brings in its dedicated infrastructure, in other European locations it is ambitious ports that are driving the availability of gas fuel. One example is Estonian utility Eesti Gaas, which has commissioned the first in a series of short-sea bunker vessels to serve the Baltic Sea around Tallinn, starting with regional ferry operator Tallink.

“Eesti Gaas and our launch client, ferry operator Tallink, will become the companies with the most LNG competence in this region,” says Eesti Gaas board member Kalev Reiljan. “Eesti Gaas has performed over 1,500 port-based LNG truck-to-ship refuellings of Tallink’s LNG-powered Megastar ferry and now we are moving on toward offshore, more mobile solutions.”

Damen Yichang Shipyard cut steel on the vessel in March. The 6,000 m³-capacity vessel and its future sister ships are intended to accelerate the adoption of LNG in the north-eastern Baltic Sea by providing a ship-to-ship bunkering service in that part of the region for the first time.

The LGC 6000 LNG vessels are designed to meet ice-class 1A certification, allowing them to operate all year in the Gulf of Finland and the northern Baltic. A dual-fuel propulsion system will be used for the management of the boil-off gas in combination with a gas burner. The vessel will host two Type-C tanks of 3,000 m3 each, with Chinese supplier Gloryholder Liquefied Gas Machinery providing the cargo handling and fuel gas supply system.

The two type-C LNG tanks will be partially open, ensuring good access and easy upgrade options as the LNG consumer market develops, Eesti Gaas said. Following sea trials, the ship will arrive in Estonia in mid-2020 and will start serving LNG clients in the third quarter. Eesti Gaas will operate the vessel under a long-term charter from parent company Infortar.