Diesel-Electric Propulsion for Offshore

By Alan Haig-Brown
Friday, March 14, 2014
Photo courtesy of Eastern Shipbuilding

Images of the Bravante courtesy of Eastern Shipbuilding, the genet on truck is courtesy of Cummins Mid-South

Long reserved for specialized applications such as icebreakers, diesel electric has enjoyed a rapid growth for marine propulsion in the past decade. Throughout that period, Cummins Marine has been a leader, supplying more than 900 diesel electric packages since delivering its first genset 2003.

Early adopters of this flexible propulsion technology included the US firm Rigdon Marine with twenty vessels and France-based Bourbon Offshore with over 100 vessels.

In late 2011 Aries Marine built two STX-designed Tiger Shark Class PSVs. After nine months operating in Mexico, one of their vessel engineers, Darrell Bickham, enthused over the performance. “We only put enough engines on line as we need for the job. We can stand by the rig outside the 500-meter zone on one of our four Cummins QSK60-powered generators. Traveling we can make 10 knots with only two operating at 50 to 60 percent of their rated power.”

Captain Philip Munsch added, “If we get into weather we can bring on three or even four engines as required. But they are always running at a steady 1,800 RPM with no revving up and down so crew comfort and safety is improved because of the reduced fatigue.”

The fuel economy made possible by using only the number of engines required to do the job at hand is pleasing to both owners and charterers. The flexibility in engine placement afforded by the absence of a long drive shaft between the generators and propulsion motors allows for engine placement on the main deck resulting in increased cargo capacity in the vessel’s hull.

There is virtually no downtime as engine servicing can be done with one or more engines off line. Modern electronic systems have made diesel electric generator sets reliable and easily managed. It is, then, little wonder that this form of powering the modern offshore fleet is gaining even more followers.

Brazil’s Bravante Group recently (February 28, 2014) took delivery of the M/V Bravante VI, their second in a five vessel series of diesel-electric PSVs, from Florida’s Eastern Shipbuilding. The Bravante V delivered in 2013 is already on charter in Brazilian waters.

Designed by STX and designated the STX SV290 design the 86.5-meter (284-foot) by 18.3-meter (60-foot) by 7.5-meter (24-foot) vessels are built around four Cummins-powered generators. Each 16-cylinder Cummins QSK60-DM engine rated for 1825 kW at 1800 RPM powers a Marathon Model 744 690VAC generator also supplied by Cummins.

A pair of 690VAC electric motors each turning nozzled fixed-pitch propellers on Schottel Combi-Drives provides main propulsion. These two propulsion motors are each rated at 2,500 kW at 750 RPM to give a total of 6700 HP. Two Schottel 1180 kW tunnel thrusters with direct coupled electric drives also draw their power from the four main Cummins QSK60-powered generators. The flexibility of the diesel electric system in providing power to both ends of the vessel as well as to a wide array of cargo pumps and general ship requirements continues to attract owners’ attention and orders.
 

  • Photo courtesy of Cummins Mid-South

    Photo courtesy of Cummins Mid-South

  • Photo courtesy of Eastern Shipbuilding

    Photo courtesy of Eastern Shipbuilding

  • Photo courtesy of Eastern Shipbuilding

    Photo courtesy of Eastern Shipbuilding

  • Photo courtesy of Cummins Mid-South
  • Photo courtesy of Eastern Shipbuilding
  • Photo courtesy of Eastern Shipbuilding
Maritime Reporter June 2015 Digital Edition
FREE Maritime Reporter Subscription
Latest Maritime News    rss feeds

People & Company News

Buoys in Disputed Waters Roil South China Sea Dispute

Buoys stretched "as far as eye could see" - Philippine sailor. The Philippine navy recently found a large steel marker bearing Chinese inscriptions and hundreds

White House: Iran Talks Deadline Could Slip

The White House said Tuesday's deadline for negotiators in Vienna to come to a final, firm agreement on Iran's nuclear program could slip. When asked if President

SUNY Maritime College to Host e-Navigation Underway 2015

The State University of New York Maritime College will host the e-Navigation Underway 2015 – North America conference from September 28 to 30 on its Throggs Neck, N.

Offshore

Research Vessel Concept a first for Voith

The new fisheries research vessel of the Shanghai Ocean University will be a first for Voith in several respects.   It is the first fisheries research vessel

Ocean Safety’s New Liferaft Facility Opens

Ocean Safety, a specialist in the worldwide supply, distribution, service and hire of marine safety equipment, has opened a new liferaft hire division.   Ocean

ISS Inks Service Pact with Technip

Inchcape Shipping Services (ISS) and Techniphave signed a contract to provide marine agency services and logistics for the Rashid C project in the Middle East. Currently

Marine Power

Research Vessel Concept a first for Voith

The new fisheries research vessel of the Shanghai Ocean University will be a first for Voith in several respects.   It is the first fisheries research vessel

MTU Powers RSN Navy's Littoral Mission Vessel

MTU to power eight Republic of Singapore Navy’s new patrol vessels. Employees and guests, including senior representatives from the Republic of Singapore Navy (RSN) and Ministry of Defence,

Hercules-2 Officially Launched

MAN Diesel & Turbo, Wärtsilä and Winterthur Gas & Diesel to collaborate on major, EU-funded project.   A major cross-industry initiative led by MAN Diesel & Turbo,

News

White House: Iran Talks Deadline Could Slip

The White House said Tuesday's deadline for negotiators in Vienna to come to a final, firm agreement on Iran's nuclear program could slip. When asked if President

SUNY Maritime College to Host e-Navigation Underway 2015

The State University of New York Maritime College will host the e-Navigation Underway 2015 – North America conference from September 28 to 30 on its Throggs Neck, N.

Port of New Orleans Goes Green

Green Marine, a North American environmental certification program for the marine, port and terminal industry, officially recognized the Port of New Orleans recently as a certified Green Port.

Marine Equipment

Tideland Introduced New Navigation Aids at Seawork

Tideland Signal Corporation (Tideland) introduced a number of new innovative aids to navigation (AtoN) products at Seawork 2015, including SB-1800, the newest member

Navis N4 TOS Open in Liverpool Terminal

Peel Ports, owners and operators of the Port of Liverpool, has achieved a major milestone in its multi-million investment program to transform the port into Europe’s

Research Vessel Concept a first for Voith

The new fisheries research vessel of the Shanghai Ocean University will be a first for Voith in several respects.   It is the first fisheries research vessel

 
 
Maritime Security Maritime Standards Naval Architecture Navigation Offshore Oil Pod Propulsion Port Authority Salvage Ship Electronics Winch
rss | archive | history | articles | privacy | contributors | top maritime news | about us | copyright | maritime magazines
maritime security news | shipbuilding news | maritime industry | shipping news | maritime reporting | workboats news | ship design | maritime business

Time taken: 0.2485 sec (4 req/sec)