Intelligent power for new pelagic vessel
Electric propulsion systems save fuel so most of the newbuilds from Denmark-based Karstensens Shipyard are designed with a floating frequency system (from 50 to 60 Hz) to optimise fuel consumption. The 80m ‘Lunar Bow’ is the fifth trawler that the Scottish fishing giant Lunar Fishing Co. Ltd. has ordered from Karstensens Shipyard. Lunar Fishing wanted a vessel designed with a combination of diesel-electric propulsion systems PTI/PTO/PTH (power take-in/ power take-off/ power take-home) operating modes.
The PTI mode (also called boost mode) adds power from the diesel generators via the shaft generator to the propeller so that the main engine and the diesel generators provide the needed power for propulsion. The PTI mode is mainly used to get the maximum effect from the propeller, meaning that the size of the main engine can be reduced. The boost mode can be used when trawling for pelagic fish like mackerel.
The PTH (power take home) mode is used in case of a failure on the main engine and will enable the diesel generators to drive electric propulsion. PTH also reduces the running hours on the main engine.
The PTO mode is when the main engine provides the power needed for both propulsion and other onboard energy consumers. PTO mode reduces fuel consumption and emissions significantly, and the PTO mode is a prerequisite when designing vessels with a floating frequency system.
"DEIF’s Delomatic-4 system is the only system that can handle floating frequency together with all the other functions required" says Tommy Falk Mikkelsen, Managing Director of KS Elektro’; a provider of electrical and electronic solutions for the maritime industry established in 2016 by Tommy Falk Mikkelsen and Karstensens Shipyard.
‘Lunar Bow’ is equipped with a 6,100 kW main engine, a 3.400 kW shaft alternator, and three auxiliary generators (2x940 kW and 200 kW). Unusually, Lunar Bow is not equipped with a traditional emergency generator. However, Lunar Bow is equipped with two separate engine rooms, enabling the system to run a generator parallel with the other diesel engines. Everything is managed automatically by the Delomatic-4 system and requires no additional input.
“The reason for applying this solution is, that the generator almost is in operation daily instead of only being used once a month, risking that this is not working when needed,” Tommy explains. “Applying this kind of system saves a small generator, and you can have a larger generator that can be used for operation instead.”
To modernise and integrate new functions, KS Elektro has implemented DEIF’s AGI touchscreen as a standard in all power management installations, providing operators with new features and a more user-friendly, modern and intuitive interface. ”In the beginning, people were a bit reluctant about the touchscreen, but it was just until they had tried using it and then they were convinced”, says Tommy. “We value the close cooperation with DEIF. We get fast, positive and competent support when we have questions or need for a new design.”