Designers at Work in 2015

LR issues Approval in Principle for joint GE Marine and DSIC gas turbine-powered LNG carrier design.

By Wendy Laursen 2015-12-29 18:13:02

The year has seen ship designers hard at work to boost the fuel efficiency of the industry and help shipowners meet upcoming environmental regulations:

Lightweight Gas Turbine Power

GE Marine and Dalian Shipbuilding Industry Company (DSIC) obtained Lloyd’s Register’s (LR) Approval in Principle (AiP) for a jointly developed gas turbine-powered LNG carrier design.

Operational benefits of gas turbines to naval architects, owners and operators include high power in a compact package and design flexibility. The gas turbine is 80 percent lighter and 30 percent smaller than comparable slow-speed diesel applications.

The LNG carrier design allows room for more cargo – some 4,000 m3 of additional space in the same size hull – along with low emissions and the flexibility to operate on LNG or liquid fuel. The LNG carrier will be built around a GE gas turbine-based COGES (COmbined Gas turbine, Electric and Steam) system that will feature one 25-megawatt gas turbine, one steam turbine generator-set and a heat recovery system including gas combustion unit. 

The carrier will allow for flexible configuration of prime movers and a total installed power of more than 50 MW, if required. The GE gas turbines can be equipped with a GE Dry Low Emissions (DLE) or single annular combustion system – both capable of meeting Tier III IMO/Tier IV United States Environmental Protection Agency requirements now with no exhaust treatment and no methane slip.

A New Series of LNG Carriers

Wärtsilä announced a new series of LNG Carrier ship designs this year. 

The series is comprised of four vessel designs, the WSD59 3K, WSD59 6.5K, WSD55 12K, and WSD50 20K, all of which have been developed in close cooperation with customers to produce vessels that are appropriate for the global LNG infrastructure and applicable for both ocean going and inland water operations. In each case, fuel economy, performance guarantees, optional versions to meet specific needs, and the flexibility to choose particular features and solutions have been emphasized.

The WSD59 3K design offers fuel consumption of 7.5 t/d at a service speed of 14 knots. The design draft is 4.75 meters. The fuel consumption for the WSD55 12K design vessels is 13.5 t/d at a service speed of 14.5 knots, making it the best in its class. The design draft is 6.2 meters. The fuel consumption for vessels based on the WSD50 20K design is also the best in its class at 18.1 t/d at a service speed of 15 knots. The WSD59 6.5K design offers a fuel consumption of 11.0 t/d at a speed of 13 knots. The design draft is 5.8 meters.

LNG Bunker Barges

This year, Crowley Maritime subsidiary Jensen Maritime developed two new, LNG bunker barge concepts that can be fully customized to meet a customer’s unique needs.

The first concept involves outfitting an existing barge with an above-deck LNG tank. The concept can be further modified to accommodate more than one type of product, if a customer has a need for multiple liquid transfers. Advantages of this design include a fast turnaround and a reduced need to invest in specialized assets if a customer has short-term LNG requirements.

The second concept is for a purpose-built, new bunker barge. Offering greater carrying capacity and improved visibility, the design features a larger LNG tank that is nestled inside of the barge. This new barge will also feature the latest safety features and efficiencies.

A Next Generation of Heavy Lift Vessels

With the introduction of the Ulstein HX103 and HX104 heavy lift vessel designs, the company paves the way for the next generation, cost efficient offshore assets to meet today’s and tomorrow’s market demand. A dedicated feature on the DP3 designed vessels is the heavy-lift capability with large outreach combined with a large open deck space and accommodation for 350 and 500 people on board. The fully SPS compliant designs also mark the entry of the successful Ulstein X-BOW in this segment of the construction market.

Ulstein has paid significant attention to combine good DP capabilities with relatively small installed power and smart DP lay-out, reducing the vessel’s overall environmental footprint. Therefore, Ulstien offers an attractive and modern vessel alternative for the maintenance markets in a.o. the Gulf of Mexico, Brazil and West Africa. 

The HX103 design includes a main crane of 1,000 tons @ 26m outreach revolving and 320 tons @ 68m, as well as a deck crane of 50 tons @ 24m outreach. Its “big brother”, the Ulstein HX104 design, has a heavy-lift capability of 2,000 tons @ 30 m radius and 685 tons @ 74 m outreach.

Energy Saving Cruise Ship

Naval architect Knud E. Hansen has designed a luxury expedition cruise ship for worldwide operation including Arctic and Antarctic regions. The vessel features a range of energy saving and emissions reductions technologies including solar and battery power provisions.

The vessel is designed for unrestricted ocean voyages and strengthened for Ice Class 1A service. It is designed for itineraries up to 21 days with 300 passengers on board, and is the result of increasing interest in smaller size vessels for specialized and customized cruising and expeditions. 

The hull is ice strengthened and has a double hull covering all hull machinery and service spaces. The ship is specifically designed to operate safely in heavy seas and high winds as well as narrow passages and small ports. There are three main fire zones and the vessel exceeds safe-return-to-port requirements. 

Propulsion and maneuverability is provided by two Azipod units and two bow thrusters. The diesel-electric power plant includes four medium-speed diesel generators in two separate engine rooms. The engines can be specified for Tier 3 NOx emission levels without exhaust gas treatment. Solar cells help offset the vessel’s electrical load and space is reserved for battery systems to provide true emission free and silent sailing for extra sensitive areas.  

Engine heat recovery systems provide all of the vessels heating requirements and innovative HVAC systems reduce energy consumption. Advanced LED lighting and smart control systems contribute further to the overall low electrical load of the vessel. The green philosophy has also been considered by a combination of highly insulated windows and outside window walls combined with latest solar power technology.  

Mega Container Ship

GTT, CMA CGM (and its subsidiary CMA Ships) and DNV GL released a technical and feasibility study for a new mega box ship today – the Piston Engine Room Free Efficient Containership PERFECt. 

The concept vessel is LNG-fuelled, powered by a combined gas and steam turbine, and is electrically driven. Exploring this novel configuration resulted in the partners identifying and analyzing a propulsion concept that has the potential to offer a more efficient, more flexible and greener box ship design than current 20,000 TEU two-stroke diesel engine driven ultra large container vessels.

The two 10,960 m³ LNG fuel tanks are located below the deck house, giving the vessel enough fuel capacity for an Asia/Europe round trip. With the gas and steam turbines integrated at deck level within the same deck house as the tanks, the space normally occupied by the conventional engine room can be used to increase cargo capacity significantly.

The dissociation of electric power generation from electric propulsion allows the electric power plant to be moved away from the main propulsion system, giving a great deal of flexibility. In fact an engine room is not needed any more. The three electric main motors, which are arranged on one common shaft, can be run fully independently of each other providing increased redundancy and reliability and a high level of safety.

With gas turbine-driven power production that utilizes a very clean fuel as well as electric propulsion, the ship’s machinery systems will be simplified and much more robust. This approach is also expected to lead to new maintenance strategies that are already common practice in the aviation industry. Such strategies would enable shipping companies to reduce the ship’s engine crew dramatically and save costs.

Best-in-Class Container Feeder

Deltamarin introduced the first state-of-the-art container vessel of its series, the A.Delta2300. This new design is based on extensive research and development work to establish the best-in-class design in terms of cargo capacity, flexibility and fuel economy. It provides a flexible platform for a whole series of designs, which can be adapted to various customers’ requirements as a result of several optional feature studies.

The development work has been supported by AVIC Weihai Shipyard in terms of construction friendliness, and has been reviewed and commented on by DNV GL considering the application of the latest rules and industry practices. Deltamarin and AVIC Weihai Shipyard are both members of the AVIC Group.

The A.Delta2300 provides a container capacity of 2,322 TEU in five cargo holds and on deck. The increased cargo hold breadth improves stability in the fully laden condition. Together with the ballast-free approach, this results in an increased utilization rate of about 73 percent (1,700 TEU) of nominal container intake in the homogeneous loading condition at scantling draught carrying a 14t TEU container. Furthermore, intake can be optimized to a specific cargo profile and even further improved by considering route-specific loading.

The high flexibility of the A.Delta2300 allows pallet-wide container stowage as well as three tiers of high cube containers in the cargo hold without losing container slots. Additionally, a high number of reefer plugs allows smart stowage and the reduction of unnecessary container movements. These features provide efficient and fluent stowage, which reduces time and costs.

The daily main engine fuel oil consumption is decreased to 42 t/day at a 19-knot service speed resulting in superior fuel efficiency of 0.033 t/TEU/day. A strikingly low deadweight per TEU ratio of less than 16 DWT/14t TEU is thus achieved, which is commonly gained only in larger container ships. This efficiency decreases the EEDI (Energy Efficiency Design Index) value to approximately 37 percent below the IMO reference line complying with Phase 3, which enters into force in 2025.

The opinions expressed herein are the author's and not necessarily those of The Maritime Executive.