The in-service and on-order fleet of LNG-powered seagoing ships has reached the 200 mark. The double century was achieved on 20 March 2017 when Sovcomflot confirmed orders for four ice-class Aframax tankers of 114,000 dwt at Hyundai Samho Heavy Industries.
The complement of LNG-fuelled vessels that are not LNG carriers comprises 103 in-service ships and 97 on order. The total represents a year-on-year jump of 23 per cent.
Twelve months ago, when LNG World Shipping last carried out a comprehensive review of the LNG-fuelled fleet, there were 74 such vessels in service and 88 on order.
The LNG World Shipping survey breaks the LNG-fuelled fleet into four categories ꟷ passenger ships; tankers and bulk carriers; containers and dry cargo ships; and service and supply ships.
Passengers and tankers
Passenger ships are the largest single segment, accounting for 72 of the 200-ship total. The in-service passenger ship fleet stands at 40 ships (up from 30 last year) while there are 32 such vessels on order (23 last year).
The 36 per cent annual jump in the passenger ship fleet owes much to the interest in clean-burning LNG as marine fuel by the leading cruise ship operators. Between them, Carnival Group, MSC Cruises and Royal Caribbean Cruises have ordered 13 newbuildings for delivery between 2019 and 2026.
The most dynamic sector over the past 12 months has been tankers and bulk carriers, thanks to a slew of shipyard completions. Avic Dingheng has handed over the four-ship series of chemical/product tankers it was building for Terntank and service on Baltic Sea routes, while four ethane carriers ꟷ three for Navigas and one for operation in the Gaschem pool ꟷ have also been delivered.
The Terntank vessels and the ethane carriers are also notable for their low-speed propulsion systems. The Terntank quartet are the first ships to be propelled by low-pressure two-stroke dual-fuel engines, in this case supplied by Winterthur G&D, while high-pressure MAN gas-injection engines were specified for the ethane ships.
Newbuilding contracts in the tanker and bulker segment have kept the orderbook topped up, even as the in-service fleet expanded from six to 19 vessels. Between them, Furetank, Älvtank and Thun Tankers, the three members of the Gothia Tanker Alliance, have ordered 10 chemical/product tankers, made up of six of 16,300 dwt and four of 8,000 dwt.
The four Aframax ships for Sovcomflot mentioned above represent another notable newbuilding programme. The vessels will be taken on charter by Shell, a company which now, following the takeover of the BG Group in February 2016, has LNG sales of 57 million tonnes per annum, or around 22 per cent of the global market.
Container ship hiatus
The container and dry cargo ship segment of the LNG-fuelled fleet is the smallest of the four and has actually shrunk over the past year. The orderbook has fallen by a third, to 14 ships, as a result of three deliveries, four cancelled contracts and the absence of any new orders to compensate.
The cancellations ꟷ two for Containerships and two for Matson Navigation ꟷ were prompted by decisions to switch shipbuilders from the originally nominated yard. In the case of Containerships the order was reduced from six 1,400 teu container ships to four while Matson opted for LNG-ready vessels from its chosen new yard rather than the LNG-powered box ships first specified.
Despite the hiatus of the past year, the container ship segment will undoubtedly grow in the years ahead, as evidenced by the United Arab Shipping Co’s current newbuilding programme of 17 LNG-ready ships, comprising six 18,800 teu vessels and 11 of 15,000 teu, and CMA CGM’s stated intention of emulating UASC’s propulsion system choice when specifying its next generation of large box ships.
Upgrading the LNG-ready capability to running on gas will happen when the necessary LNG bunkering infrastructure is in place, not least on the key Asia/Europe container ship trade route. The transformation will create the most LNG fuel-intensive vessels afloat.
The service and the supply vessel segment has been the subject of least change over the past year, both the in-service and on-order fleets rising by three vessels, to 33 and 23, respectively.
Platform supply vessels (PSVs) figure prominently in the operational LNG-powered service and supply vessel fleet, accounting for 20 of the 33-ship complement. The orderbook, in contrast, shows much more variety, with a portfolio encompassing dredgers, a jack-up rig, a semi-submersible crane vessel, a cable-layer and a windfarm installation vessel.
DEME of Belgium has been a leading advocate of LNG-fuelled dredgers and has investigated the challenges of using gas to power such vessels. Factors to be weighed up include bunker tank size and location, LNG bunker availability, shipboard bunkering connections, crew training and the step load capability of the various gas-burning engine options.
In combination with its cold box encasement, an LNG Type C bunker tank occupies about three times as much space as a tank of marine gas oil (MGO) possessing the same energy content. Accommodating LNG tanks has a significant impact on vessel layout, while the tank location restrictions imposed by the new International Code of Safety for Ships using Gases or other Low-Flashpoint Fuels (IGF Code) add another level of complexity to the design challenge.
Naval architects working on the DEME dredgers found that dual-fuel diesel engines worked best for the vessels due to their better step load capability than gas engines. Such propulsion units also allowed the vessels to be provided with a mix of LNG and MGO bunker tank capacities.
The aim is to optimise the use of LNG, assuming the cost of this fuel is lower than MGO, but to provide sufficient MGO as a backup. The crew would switch to MGO if the dredger has to operate longer than planned before the next LNG bunkering stop.
The average size of the 97 LNG-fuelled ships now on order is notably greater than that of the 88 ships in last year’s orderbook. This reflects not only the acceptance of LNG fuel among owners of a growing array of ship types but also recognition of the fact that the 0.5 per cent global sulphur cap will be implemented in 2020 rather than the alternative 2025 date.
The four 180,000gt vessels that AIDA and Costa, both Carnival Group companies, have on order at the Meyer Papenburg and Meyer Turku yards, for example, will be able to carry up to 6,600 passengers, giving them the largest guest capacity of any cruise ship.
Each ship will be fitted with three Type C LNG bunker tanks with an aggregate capacity of 3,600m3, enabling their dual-fuel engines to operate on gas for up to 14 days before the need for replenishment.
Although the LNG bunker tank capacity of the Aframax tanker quartet just ordered by Sovcomflot is yet to be announced, they would require about 5,500m3 of space to provide the vessels with the same amount of energy contained in the heavy fuel oil tankage typically specified for such ships.
While smaller ships for operation in emission control areas (ECAs) and on dedicated regional routes will continue to dominate the LNG-fuelled vessel orderbook, the growing presence of larger ships is encouraging the LNG market. The need for more extensive bunkering infrastructure is reinforcing the momentum now building for LNG as marine fuel and raising hopes for another year of 25 per cent growth in the LNG-fuelled fleet.