Esvagt Froude Service Operation Vessel (SOV)

By March 30, 2015 Article, Technology No Comments

Esvagt on a Roll
Esvagt Froude is the first service operation vessel (SOV) made to the Havyard 832 design. This is the first time that such a large vessel will be used to service offshore wind farms. These vessels transport crew and cargo to and from offshore wind farms.

Shipbuilder Havyard Ship Technology built the vessel at its yard in Leirvik and delivered the same to its Danish owner Esvagt in February 2015. Havyard Design & Solutions designed the vessel. Esvagt Froude’s sister ship Esvagt Faraday will be delivered in April 2015.

Havyard 832 Design (Source:

Havyard 832 Design

Esvagt’s fleet now stands at 41 and the company has come a long way since early 1980s when it provided stand-by vessels to the oil and gas industry. With this, Esvagt has diversified into servicing wind-farms and will receive the third Havyard 832 SOV in September 2016.

This vessel purchase spree represents Esvagt’s largest combined investment and takes the company closer to its goal – to be the preferred provider of Emergency Response & Rescue and Offshore Wind Services.

Technical & Other Details
Siemens Wind Power has chartered Esvagt Froude for five years to service its Baltic II Offshore Wind Farm. Esvagt Faraday will serve Siemens’ Butendiek Offshore Wind Farm in German North Sea for ten years. Both contracts include an extension clause. The third vessel will service the Dudgeon Wind Farm being developed by Statkraft and Statoil off the coast of Norflok, UK.

Havyard had the hulls built at Cemre Shipyard, Turkey and conducted equipment installation, testing, and commissioning at Leirvik Shipyard, Norway. The broad objective was to derive maximum safety, reliability, efficiency, maneuverability, and comfort in all sea states.

Esvagt Froude uses the following methods for transporting personnel and equipment to offshore turbines:
• Walk-to-Work Ampelmann A-Type Gangway enables technicians to walk from the vessel directly to the offshore turbine
The gangway uses a hydraulically stabilized asymmetric bridge that personnel can use even in waves of 2.5m height. Plus it has an active and passive roll damping system for improved operations and comfort

Safe Transfer Boats complement the walk-to-work gangway system. These include:
• ESVAGT STB® 7B Safe Transfer Boat accommodates three technicians, two crew members, and equipment
• ESVAGT STB® 12A Safe Transfer Boat can transport one ton cargo along with two crew members and eight technicians
• ESVAGT FRB 15C Fast Rescue Boat

Special features:
• Asymmetric Bridge for gangway operations
• Active and Passive Roll Damping System for optimized gangway operations and for minimizing unnecessary movements to improve comfort

Technical Specification

Technical Specification

• Advanced Transit for personnel
• Top ERN Score lends it with superior station keeping for operations even during rough weather. Classification Society Det Norske Veritas (DNV) developed the ERN score in the 1970s. ERN values range between 0 and 99
ERN stands for Environment Regularity Number and is a theoretical method of determining the ability of a vessel to maintain its position during diverse sea and weather conditions. Only lateral forces such as waves, winds, and currents are considered and this makes the calculations fairly simple
• Cutting Edge Dynamic Positioning (DP) Navigation System enables skilled maneuvering when plying inside wind farms. It also allows placing personnel as close as possible to the turbines for better safety
• Innovative Diesel-Electric Propulsion with DC Power System for best fuel efficiency and comfort
• Compactor and Incinerator for handling waste
• Boat Landing Ramp at Aft for connecting with STB® 12A or catamaran transfer vessels (CTVs)
• CCTV Surveillance

Dynamic hull design combined with Siemens’ innovative diesel generator ensures top comfort. Four identical 1650kW diesel generators comprise the vessel’s power plant. Unlike conventional diesel generators that maintain constant speed at all loads, Esvagt Fourde’s generators change speed with load for low fuel use and low emissions.

This DC generator system also provides high redundancy levels. The vessel uses a 700kW forward thruster and 1,600kW main azimuth thrusters as per the options available in the Havyard 832 design.
Superstructure hosts accommodation facilities complete with meeting rooms, entertainment venues, cabins, and fitness avenues. The vessel has a deck crane of 2 tons capacity and 12m outreach.

Esvagt Froude comes with a lot of promise loaded as it is with a unique gangway and propulsion system. And with two more such vessels to come, offshore wind turbines can look forward to being pampered.