The use of LNG as a fuel is growing in popularity for ships of different sizes and power to provide a solution to increasing fuel costs and reducing exhaust emissions. Using LNG requires storage not only under but also at low temperature. Cooling the gas into a liquid state at the low temperature of approximately -162 ̊C (-260 ̊F) allows it to be maintained at the low pressure of only 3.6 psi (0.25 bar). While cooling plant and well insulated tanks are feasible on a ship, on small vessels - boats, this is not practical. To access the benefits of natural gas operation, a more practical solution for boats is to use compressed natural gas (CNG). The drawback is that CNG is 2.4 times greater in volume than LNG.

In the Netherlands ten percent of automobiles run on LPG and a very small number of boats use is as a fuel, however its use in boats is regarded as being potentially dangerous as it is heavier than air and any escaping gas will accumulate in the bilges. Natural gas on the other hand is lighter than air and any escaping gas is lost to the atmosphere.

Caption: The CNG Water Police 18 ft RIB used to patrol the Netherlands inland waterways and canals.
Image Credit: K.Henderson

This year the Water Police that patrol the Netherlands inland waterways are experimenting with a dual fuel gasoline / CNG Honda outboard powered patrol boat. The boat is a 18 ft (5.6 m) Dolphin RIB powered by a Honda 90 VTEC outboard. In addition to the standard gasoline tank, there is a 24 US gall (90 liter) CNG tank with a capacity for 33 lbs (15 kg) of CNG, held under pressure of approx 3,000psi (~200 bar). The fuel system cold starts on gasoline and when operating temperature is reached switches over automatically to CNG and remains operating on gas under 2,000 rpm. Above that speed it switches over to gasoline to realise the full power of the engine.

In practical terms, the boat can patrol all day on one tank of CNG, when speed is required, it is always available and the performance of the boat is not impaired in any way due to the dual fuel capability. The fuel cost of CNG compared to gasoline in the Netherlands is about half, giving a substantial through life cost saving.

Caption: The 24 gall / 33 lbs CNG fuel tank mounted in the bilges.
(GROENGAS is Dutch for Green Gas!)
Image Credit: K.Henderson

Unmanned surface vessels took a step further toward becoming a reality when a U.S. Navy research and development programme attained its first objective –  to build and demonstrate a vessel on the assumption that no person steps aboard at any point in its operating cycle.

The Textron Common Unmanned Surface Vessel (CUSV) vividly met this objective during the Navy’s 2011 ‘Sea Warrior’ experiment at Hampton Roads near the Norfolk Naval Base, clearing the way for subsequent Federal Government invitations to tender for work on the remaining objectives set out by the Defense Advanced Research Agency (DARPA) in its Anti-submarine Warfare Unmanned Vessel Continuos Trail (ACTUV) programme. A project aimed to develop an unmanned X-ship optimised to robustly track quiet diesel electric submarines.

Patrol Boat – Unmanned & Autonomous: Photo courtesy of AA! Systems

Fleet-Class Common Unmanned Surface Vessel by Textron

Not only was the unmanned patrol boat in the Norfolk trials able to intercept and warn off an intruding vessel – click here for video – by means of a threatening pre-recorded loud-hailer ‘Level 1’ order, but with DARPA’s anti-submarine warfare requirements in mind the boat's equipment bay was able to contain a submarine-tracking, robotic device.

The patrol boat autonomous control system incorporates a developed obstacle-avoidance technology that Navy researchers call ‘Sliding Autonomy’ that offers a range of capability from fully autonomous operation to man-in-the-loop intervention.

‘Sliding Autonomy’ modes range from the most basic, in which the operator has direct manual control over the rudders and engines individually, to semi-autonomous modes with a specified speed and course, to full autonomous mission mode using the vessels collision avoidance system. In addition, it allows users to create a single, seamless operational network of airborne, sea-based and ground-based assets from ship to shore, shore to ship, or ship to ship.

Textron has developed its multi-purpose ‘Fleet-Class’ CUSV incorporating AAI's (AAI is an operating unit of Textron Systems) unmanned maritime command and control station as part of a multi-warfare, multi-mission and multi-payload solution. The CUSV includes:

 AAI's common command and control system; data link; reconfigurable and versatile payload bay; common payload launch and recovery controller; and modular USV system open architecture using commercial, off-the-shelf technology.

Patrol Boat Equipment Launch Bay: Photo courtesy of AAI Systems

The 'Fleet Class' CUSV is of modular construction, capable of executing mine warfare; anti-submarine warfare; communications relay; intelligence, surveillance and reconnaissance; anti-surface warfare; and UAS/UUV launch and recovery missions.

Now that an unmanned craft capable of sophisticated collision avoidance has been demonstrated one wonders if an unmanned autonomous vessel (with that ‘man-in-the-loop’ control condition) might be developed not only for military purposes, but also for commercial merchant shipping operations. Perhaps an offshore support vessel to begin with; beyond doubt the crew-less vessel offers considerable financial and organizationnal benefits to ship owners.

Wing-in-Ground (WIG) craft development took a firm step forward with the recent announcement that two Korean companies –  Daewoo Shipbuilding & Marine Engineering (DSME) and Wing Ship Technology Corp –   are to co-operate to make production of WIG craft a viable operating and commercial proposition. The offshore support vessel market is in their sights, and they also have plans to develop a 200-seat WIG craft for military use.

Wing Ship Technology successfully produced their 50-seat prototype WSH-500 (classed by Lloyd’s Register) late last year with $6.3 million funding assistance from DSME.

Wing-in-Ground Effect Craft WSH-500: Photo courtesy of Wing Ship Technology Corp.

WIG Concept & Maritime Safety

A WIG craft is a vessel capable of operating completely above the surface of the water on a dynamic air-cushion. The 'ground effect' refers to what a pilot (commonly passengers too ) feels when landing a large aircraft – just before touchdown it’s as if the plane wants to go on and on – due to the cushion of air trapped between the wings and the runway. Hence ‘aerodynamic ground effect’.

Presently there are no safety standards in place for WIG craft, although the International Maritime Organisation (IMO) did publish interim guidelines ten years ago. The United States Coast Guard, in conjunction with the Federal Aviation Administration and the IMO (a pairing that underlines the WIG concept’s intersection with both air and sea) say this is a work in progress.

Propulsion & General Particulars WSH-500

Gas Turbine Engine by MTT & Shaft Prop: Photo courtesy of MTT

US-based MTT Corp was contracted to design the special 1,400 hp gas-turbine propulsion systems for the WSH-500 to drive customised 10 ft propellors developing 4,800 lbs thrust.

German naval architect Hanno Fischer, a pioneer in WIG craft development, brought his expertise to bear on the Korean initiative by Wing Ship Technology (founded in 2007) to develop the WSH-500, and the builders say they intend four vessels for delivery in the current year at a price of about US$ 6.7 million each for the basic configuration.

Principal particulars are as follows:

• Passenger capacity: 47 passengers and 3 crew
• LOA: 28.5 m (93.5 ft)
• Breadth overall: 27 m (88.6)
• Height: 6.7 m (22 ft)
• Displacement: 17.1 tons
• Construction material: aluminium alloy
• Propulsion: MTT gas-turbine: 2 x 1,400 Turbo-shaft/Prop
• Cruising speed 100 kts (on trial achieved 73 kts in GE mode)
• Fuel: 1 tonne capacity, consumption about 250 kg/hr
• Range: 300 (162 nm)
• Cruising height: 1 to 5 m (3.3 to 16.4 ft) with safe landing at all times

WIG Craft Advantages

High speed transportation without the need of an airport is the great advantage. Speeds of a light aircraft or helicopter are capable of being matched, but require less redundant systems as the craft can land quickly and smoothly in an emergency.

The designers reported good stability and minimal pitch and roll during sea trials of the WSH-500 in air-borne operating mode, assuring passenger comfort.

DSME vice president Y.Y. Koh said WIG craft are well suited to meet the needs of the offshore market, considering that they were safer and more economical than widely-used helicopters.

Italian builder Fincantieri, together with engine manufacturer Wärtsilä and designer Stefano Pastrovich have put forward a megayacht concept called X-Vintage, using the dual fuels of LNG and MGO.

Caption: The handsome lines of the 325 ft X-Vintage megayacht.
(Note: the mast in the stern belongs to one of the catamaran "toys")
Image credit: Fincantieri / Stefano Pastrovich

Looking towards the impending IMO Tier 3 regulation deadline of 2016 and the expected expansion of Emission Control Areas, the concept avoids the necessity of having to incorporate exhaust treatment equipment to ensure compliance with the forthcoming regulations. The availability of LNG refueling centers is numerous throughout the world with many further stations planned in the future.

The major obstacle in designing a megayacht to operate on dual fuel is the location of the voluminous gas storage tanks. If added as an afterthought rather than a fundamental part of the design, many compromises would be required, not to mention the very important item of pleasing appearance.

In the X-Vintage, the twin tanks are located forward of the “garage for toys” where the headroom, out of necessity to accommodate some of the toys, is greater than on the other decks.

The motoryacht has an LOA of 325 ft (99 m), beam of 51 ft (15.5 m) and draws 15.7 ft (4.8 m). A twin shaft electric propulsion system is specified with six Wärtsilä 6L20DF dual fuel generators each rated at 1,056 kW at 1,200 rpm. The choice of six smaller gensets provides redundancy and allows great flexibility in their operation at optimum efficiency.

The advantages of LNG operation not only reduces harmful exhaust emissions but is considerable less expensive in fuel costs. It is therefore to be expected that it will not be very long until LNG will become more widely used to fuel megayachts. To retain the possibility of MDO operation, the preference favors the dual fuel engine.

Caption: A phantom drawing of the X-Vintage megayacht showing the locations
of the LNG and diesel fuel tanks, propulsion system and exhaust.
Image credit: Wärtsilä Corp

DNV is heading the project FellowSHIP which is the name given to a joint industry R&D project to investigate sustainable energy generation for marine and offshore applications. The other partners are the owner of the test ship MV Viking Lady, Eidesvik Offshore and ship designer/power electronics developer Wärtsilä with overall financial support for the project being provided by the Research Council of Norway.

Caption: The hybrid 6,200 dwt MV Viking Lady Offshore Supply Vessel, owned by Eidesvik Offshore,
is the world’s first application of a merchant ship using fuel cell propulsion.
image credit: Eidesvik Offshore

The 6,200 dwt MV Viking Lady Offshore Supply Vessel was built in 2009 and has an LOA of 300 ft (92 m). beam of 69 ft (21 m) and draft of 31.5 ft (9.6 m). There are four Wartsila 6L34DF gensets each with an output of 2.6MW able to run on diesel or LNG (Liquefied Natural Gas) fuel. In addition there is a MTU 330kW fuel cell operating on LNG, which is the world’s first application in a merchant ship of a fuel cell providing propulsion power. Since its installation in 2009, it has been running successfully for over 18,500 hours.

The first phase of the FellowSHIP project started 2003 with a feasibility study, development of concepts and initial design studies. The second phase (2007-2010) finalized the development and installation of the marinizied fuel cell power package and its integration with new electronic systems, power electronics and control systems technology. The project also includes safety and reliability studies and approval and rule development.

The third and final phase (2011-2013) adds an energy storage capability in the form of a battery pack thereby creating a full hybrid energy system. The battery is a lithium-polymer type with a solid polymer composite electrolyte and is built up from 6.5 kWh modules to give a total capacity of 0.5 MWh and is capable of delivering 5MWh over a short period of time. A full scale hybrid installation would be expected to include a 2 - 3 MWh battery pack, but the 500 kWh pack is sufficient to demonstrate the technology. The battery pack and battery management system, supplied by Corvus Energy, Canada, is being tested on land will be installed on board in 2013.

Compared to a traditional ship, MV Viking Lady has annually reduced harmful NOx emissions by 180 t, an amount equal to emissions from 22 000 cars. CO2 emissions are reduced by 20 percent. A future hybrid power solution including LNG-fuelled steam turbines and fuel cells, could reduce the ship’s fuel consumption by up to 30-50 percent, CO2 emissions by up to 50 percent, and NOx , SOx and particle emissions to negligible values.

Caption: Cutaway drawing of the MTU 330kW fuel cell operating on LNG,
onboard the MV Viking Lady. Since its installation in 2009, it has been running
successfully for over 18,500 hours.
Image credit: MTU Friedrichshafen

Electric power has been used for marine propulsion since 1903 when the first multi engine diesel powered ship, the 800 ton M/V Vandal was launched in St Petersburg, Russia. Many electric power variations have been developed since then, from the steam turbo-electric liners of the 1930s to nuclear propulsion systems and with increasing popularity in the last decade with the introduction of hybrid systems - all using electric motors to turn the propeller.

Caption: M/F Eiksund, a RoRo car and passenger ferry of LOA 160 ft (49 m) uses the
ΦDRIVE direct diesel electric propulsion system.
Image credit: Wikipaedia

Controlling the generators and managing the power has produced a large variety of systems that claim to increase efficiency while simplifying their operation through automation. Each system has its pros and cons with some working better than others.

The Norwegian company Inpower A/S has produced a direct diesel electric propulsion system called  ΦDRIVE (Phi drive) which they claim is as flexible as a conventional diesel-electric system, yet offering the same levels of efficiency, simplicity and robustness as a conventional diesel mechanical system. It can control single or multiple drives up to approximately 5MW.

The ΦDRIVE is based on directly coupled, permanent magnet machines thus reducing the use of power electronics with associated energy losses; consequently the drive achieves an improvement in efficiency. Compared to traditional diesel-electric machinery, the use of permanent magnet machines also has the benefit of a more compact installation freeing up valuable revenue producing space on board commercial vessels.

Last year a ΦDRIVE installation was completed in the M/F Eiksund, a RoRo car and passenger ferry of LOA 160 ft (49 m), beam 34.7 ft (10.6 m) and draft 10.2 ft (3.1 m). Power is produced by two Volvo Penta D12 gensets each of 370 kW at 1,800 rpm driving two steerable thrusters. Speed is controlled by varying the diesel engines between 600 to 1,800 rpm.

The drawing below demonstrates the relative simplicity in a twin engine installation of the ΦDRIVE direct diesel electric drive compared to a conventional mechanical drive and a representative diesel electric drive.

Caption: Simplified installation schematic comparing (l to r) conventional mechanical drive,
ΦDRIVE direct diesel electric drive, and diesel electric drive.
Image credit: Inpower A/S

Austal is to supply the Australian Customs and Border Protection Service with a fleet of eight Cape Class Patrol Boats to be built at its shipyard in Henderson, Western Australia. The 350 million Australian $ (approximately US $ 375 million) contract includes through life support for a minimum period of eight years with options to extend for various periods up until the expiration of the 20-year life of the vessels. Construction of the first hull is due to commence this month with completion planned for March 2013.

Caption: The Austal Cape Class patrol boat has a maximum speed of 25 kn and range of
over 4,000 nautical miles at a cruising speed of 12 kn. 
Image credit: Austal

The Cape Class is designed to have a greater range, endurance and flexibility, than the present Austal designed Bay Class that has been in service for over ten years. A motion control system comprising roll fins and trim flaps provides enhanced sea keeping capabilities in more severe weather conditions.
 
The new vessels have an LOA of 190 ft (58 m), beam 34 ft (10.3 m)10 ft and draft of 9.8 ft (3.0 m). Power is supplied by twin Caterpillar 3516C diesel engines, each rated at 2,525 kW (3,385 hp) at 1,800 rpm driving fixed pitch propellers via ZF 9055A reverse reduction gears. The maximum speed is 25 kn and range is over 4,000 nautical miles at a cruising speed of 12 kn. 

Two 7.3 m RIBS are carried for interception / boarding duties in addition to an inflatable ship’s boat. Each vessel will be named after Australian geographical capes: Cape St George (ACT), Cape Byron (NSW), Cape Nelson (Victoria), Cape Sorell (Tasmania), Cape Jervis (SA), Cape Leveque (WA), Cape Wessel (NT) and Cape York (Queensland).

Delivery date for the completion of the contract for all eight vessels is in the third quarter of 2015.

Caption: drawing of the Austal Cape Class patrol boat
Image credit: Austal

The striking appearance of the remarkable GHOST high-speed attack craft revealed to the public last year by Juliet Marine Systems, Inc., (JMS) of Portsmouth, NH, applies supercavitation technology to offer new capabilities in high speed craft performance.

Caption: GHOST, at rest with hull immersed during recent sea trials.
Image credit: PRNewsFoto/Juliet Marine Systems, Inc.

Although few propulsion details have been released what we do know is that the vessel has a centre hull and two movable sponsons allowing the main hull to run clear of the surface at higher speeds. At rest the sponsons move horizontally outward allowing the center hull to lower and float on the surface: thereby allowing the crew and cargo or passengers to embark / disembark. 
At speed the wings carrying the sponsons move to a position approximately 30 degrees from vertical raising the center hull clear of the water surface.

Despite the scant details of the propulsion system as yet made public, propulsion power is provided by “gas turbines.”  Looking at the material available, there are large grilles on the side of the main hull, suggesting that behind them the gas turbine are located - probably two in number, possibly driving generators.

Caption: GHOST showing the torpedo-like sponsons
Image credit: PRNewsFoto/Juliet Marine Systems, Inc.

The sponsons somewhat resemble the shape used in some SWATH designs but are perfectly round like a torpedo. I’m guessing but probably within the torpedo shaped sponsons are electric motors powering pulling propellers, perhaps counter-rotating. As to the supercavitation technology, the Soviet Union developed a supercavitating torpedo in the 1970's called Shkval (Russian for squall), with a speed in excess of 200 kn. It is rocket powered and ducts some of the exhaust gases to the front of the torpedo so it slides through the water in a gas bubble cloud. JMS however, is not claiming speeds anything like this but in the absence of detail, perhaps ducting the gas turbine’s exhaust gases to the torpedo, is part of the “secret” of GHOST - time will tell!

Caption: Artists impression of GHOST at speed.
Image credit: Juliet Marine Systems, Inc.

Research and development applied to Lithium-ion batteries (increasingly used as 'energy storage banks' in hybrid marine powered propulsion systems in workboats and leisure craft due to their high energy density) has recently revealed ways to make these batteries safer, cheaper yet with better performance. The relevant research findings come from John Hopkins University Applied Physics Laboratory (APL) and from Japan's National Institute of Advanced Industrial Science and Technology (AIST).

Lithium-ion Battery Bank: Photo US Federal Govt.

Inexpensive Sensor Warns of Lithium-ion Battery Failure

Battery malfunctions (and occasionally fires) occur in all Lithium-ion powered applications ranging in size from the cellphone right through to large hybrid or electrically powered plant and present a safety challenge to manufacturers. Typically such catastrophic failures result from ‘thermal runaway', which occurs when a cell in the battery reaches a critical temperature.
 
Searching for early-warning of such catastrophic failure, researchers at John Hopkins APL discovered an intrinsic relationship between the internal temperature of Lithium-ion cells and an easily measured electrical parameter of the cell. A small alternating current applied at specific frequencies is modified by the cell in a way that is directly related to the temperature of the critical electromechanical interface between the electrodes and the electrolyte.
 
Researchers were able to measure the temperature of the layers of the cell where thermal runaway begins by connecting the new sensor at the positive and negative terminals, using power from the battery being monitored; by this means unsafe  thermal conditions could be detected at the critical moment they occur and before the cell vents or sets itself on fire. APL has applied for patents for their invention and is on the lookout for licensing opportunities.

Lithium-ion Batteries – Cost Reduced, Performance Enhanced

The target of the research conducted at AIST in Japan has been to reduce the cost of Lithium-ion batteries (rare-earth metal Lithium is expensive) not only without loss of performance, but also to improve upon it. To achieve this they concentrated their research on replacement of the most expensive Lithium positive electrode (key in determining battery capacity and operating voltage) by other materials – mainly the most inexpensive of all – iron, in combination with titanium-substituted lithium manganese oxide.

The AIST team's research goal is to make available these new materials, proven successful as a cheaper and more effective alternative component of the Lithium battery, to the battery manufacturing industry by 2013 and the cost benefits should begin to filter down the supply chain not too long after that.


 
 
 
 



 

 

 

 
 
 
 
 
 
 

One of the most unusual boats showing at this season’s Boat Shows is the amphibious Iguana 29. Designed by architect Tanguy Le Bihan of Agence Fritsch Associés and built by Iguana Yachts, all based in France, the original concept was devised in 2007. It was first presented to the public as a model at last year’s Paris Boat Show, ten months the full sized boat was exhibited at the Cannes and later Paris, Shows this year.

Caption: Iguana 29 going through her paces with the magnificent Mont St Michel, France, in the background.
Image credit: Eric Sander

The unique feature of this boat is its twin fully retractable caterpillar tracks enabling it to negotiate a wide variety terrains with effortless ease. Power for the hydraulically operated tracks is delivered by a dedicated onboard 40 hp engine: propelling it up to 5 mph: steering on land is easy using a joystick. The design of the tracks is proportioned to give a low ground pressure, in fact it is less than that of an adult standing.

Caption: A closup of the caterpillar track mechanism: it retracts fully into the hull when at sea.
Image credit: Eric Sander

The boat weighs around 2 tons and has a length of 28 ft (8.6 m), beam of 8.2 ft (2,5 m) and a draft of 17.5 inches (0.45 m). Powered by a single 300 hp outboard, it can achieve a top speed of about 35 kn. The layout of the boat is simple and uncluttered with a capacity of 10 passengers and lots of stowage space.

The attributes of the Iguana 29 are particularly attractive for its use as a tender. No longer is the task of going ashore confined to a harbor quay or jetty, Iguana 29 can more or less land anywhere! The price tag in France, excluding tax (19.6% VAT) is EUR 184,000, approximately US $ 240,000.

Caption: Testing the Iguana 29 on a nearby beach in Normandy, France
Image credit: Eric Sander