Published 2006-12-21
By Kristian Kahrs
The environment is a top priority for the Norwegian shipping industry. Therefore current initiatives include using fuel cell technology to bring about the possibility of ultra-clean ships, technology to clean ballast water, and the introduction of ship engines powered by liquefied natural gas (LNG) instead of conventional diesel engines.
LNG to Fuel Modern Ships
The Höegh Trooper vehicle carrier was retrofitted with the OceanSaver ballast water treatment system. The treatment system won a Seatrade award in April 2006 for its technology.
© OceanSaver
Using LNG to fuel modern ships has many advantages, and the technology is currently at use in five ferries in western Norway operated by Fjord1. Norwegian companies are involved in almost all aspects of the project – LMG Marin in Bergen is responsible for the design, the Norwegian division of Rolls-Royce Marine produced the engines, and the ships were built by Aker Yards in Brattvåg.
Geir Rise is the design manager at LMG Marin, and he is proud to present a new generation of vessels with highly reliable gas configuration, thrusters, main machinery and manoeuvring systems.
“Gas-electric LNG-fuelled ferries have high transport efficiency, are environmentally friendly, and have capacities arranged for today’s traffic and for estimated increases in transport volumes in the operation period,” Rise said, adding that safety levels are equal to or better than traditional diesel-fuelled ferries.
LMG Marin has carried out technical-economic analysis which concludes that LNG is a very economically favourable fuel for ferries, high-speed ships and other ships, especially when the price of oil is high.
Leif-Arne Skarbø is a project manager for the LNG ship engine project for Rolls-Royce Marine, and he sees a great potential for gas-fuelled ships in addition to ferries.
“At the moment we are in the commissioning phase, and we believe that this project is going to be a spearhead. We have many shipowners who are interested in this technology,” says Skarbø, who sees many potential markets. Supply vessels and production ships have already utilized the technology.
“We see great markets in the Baltic area, the English Channel, and the North Sea, and there is a lot of infrastructure in the Arctic Ocean with massive traffic and many ships not leaving the area,” Skarbø explains.
However, one challenge with LNG-fuelled ships is that they require a lot of volume for fuel. While some ship types have available void spaces that can be utilized for LNG tanks, the logistics for LNG distribution are still in their early days.
“The environmental benefits of LNG ships are great. Pollution from gases like CO2, sulphur and nitrogen oxide (NOx) will be dramatically reduced. CO2 will be reduced by 25 percent,” Skarbø says. “There is no sulphur in LNG, and therefore shipowners avoid penalty taxation. Furthermore, by using these engines we reduce NOx by 90 percent and thus reduce the NOx tax by 90 percent.”
Microorganisms from Port to Port
The Viking FellowSHIP is a small-scale model powered by hydrogen and fuel cells. A full-scale demonstration of technology from the “FellowSHIP” programme is planned to be realized in 2008, using gas fuel.
© DNV Research
In the world of global shipping, non-native aquatic organisms are easily transported from port to port in ships’ ballast water. It is therefore essential to make sure that water discharged from the ballast tanks is clean. The Norwegian company OceanSaver has developed a solution for this with its OceanSaver ballast water treatment system. The system won the prestigious “Protection of the Marine and Atmospheric Environment” Seatrade Award in April 2006 for its technology.
Stein Foss, managing director at OceanSaver, explains that the company’s system provides compliant ballast water treatment, and at the same time also offers efficient corrosion control and coating protection of the steel structure in the ballast tanks – providing a potential life extension for ships.
“Our system combines a number of physical processes exposing ballast water organisms to pressure differentials, causing the rupture and destruction of organisms’ cell membranes. This leaves the ballast water compliant with the stringent IMO Ballast Water Performance Standard and also deficient in oxygen – which significantly reduces the rate of corrosion,” Foss says.
Cleaning and maintaining ballast tanks has been a challenge, but Foss believes the maintenance costs will be dramatically reduced. Furthermore, for vessels to be safe, their structural integrity must be sustainable. “In order for the ship’s structure to be sustainable, it is necessary to protect the steel surfaces with coatings. The OceanSaver system prevents creep corrosion and protects the applied coatings – and thus structural integrity is maintained.”
“The fact that the system combines efficient ballast water treatment with reduced corrosion is a unique advantage. Reduced corrosion in ballast tanks alone provides great savings,” says Foss.
Ultra-Clean Ships
With increased oil prices, increased fuel costs is a great problem faced by shipowners in modern shipping. The “FellowSHIP” programme initiated by Det Norske Veritas (DNV) hones in on this predicament by integrating hybrid fuel cell systems with conventional power machinery run on gas.
Together with the companies Wärtsilä Automation Norway, Eidesvik Offshore, MTU CFC Solutions, Vik-Sandvik, Wallenius Marine and Wärtsilä Corporation, DNV is developing technology to help bring about ultra-clean ships.
DNV project coordinator Tomas Tronstad is proud to introduce technology that can dramatically reduce hazards from poisonous gases to the environment.
“The FellowSHIP technology will be up to 50 percent more efficient than today’s diesel power, while at the same time there will be no emissions of NOx, sulphur oxide (SOx) or particles. The CO2 emissions are reduced by 50 percent compared to diesel engines run on oil,” he says.
Fuel cells differ from batteries in that they are designed for continuous replenishment of the reactants consumed; they produce electricity from an external supply of fuel and oxygen as opposed to the limited internal energy storage capacity of a battery.
“In a fuel cell, the absence of a combustion process, which otherwise would produce nitrous oxides and particles, allows for completely pollution-free conversion of energy,” Tronstad explains, adding that the technology is inherently silent and vibration free – as there are no moving parts except for supporting systems.
Plans include installing a 330 kW MCFC fuel cell onboard an offshore supply vessel in 2008. This will be the first fuel cell system developed for auxiliary and propulsion power to be placed onboard a merchant vessel, and there are great potential savings in utilizing this new technology.
“A DNV study of anticipated environmental requirements for ships in the future reveals that a fuel cell ship will see drastically reduced operating costs due to the introduction of incentive mechanisms for reducing air emissions,” Tronstad says.