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Ultra Slow Ships

Final Report Summary - ULYSSES (Ultra Slow Ships)

Executive Summary:
With climate change coming to the forefront of society’s perception, there is increasing pressure on all industries to CO2 emissions through increased efficiency and the maritime industry is no exception. The objective of ULYSSES is to demonstrate, through a combination of ultra slow speeds and complementary technologies, that the efficiency of the world fleet can be increased to a point where the following CO2 targets are met :
• Before 2020, reducing greenhouse gas emissions by 30% compared to 1990 levels.
• Beyond 2050, reducing greenhouse gas emissions by 80% compared to 1990 levels.

ULYSSES focuses on bulk carriers and tankers as these ship types produce 60% of the CO2 from ocean-going vessels . As bulk carriers and tankers are reasonably similar in design and operation, it is felt that investigating these ships will give the best value for money in terms of potential impact of the project. Additionally, it is more technically challenging to reduce the speed of these ship types as they are relatively slow speed already and therefore it is expected that directional stability and other seakeeping issues will arise. However, the results of the project will be directly transferable to other ship types.
To achieve these goals, it is expected that the target speeds will be:
• Phase I - Existing vessel in 2020: ~10 knots
• Phase II - New vessel built in 2020: ~7.5 knots
• Phase III - New vessel built in 2050: ~5 knots

It is expected that over the next five years or so there will be massive over supply of ships due to over enthusiastic ordering in the boom years. ULYSSES project contributes to absorb this over supply since more ships are required to maintain the same cargo rate while reducing the ship speed.

The project started on 1st January 2011. Over the 3 years of the project technical solutions to reduce emissions have been developed and the effort of all partners have been put together in order to create the most efficient ship possible with today technology, within the constraints of the project.

Project Context and Objectives:
The project consisted in the following main aspects:

Requirements and Evaluation
As a first step, the framework and background for the concept of “Ultra Slow Ships” that will be used by the project have been defined. Economical, safety and environmental requirements have been defined, involving relevant stakeholders from the consortium and the Advisory Committee members. This work gave insights on the different parameters of choice when designing a new efficient slow steaming ship. Specifications have been produced for the optimization of bulk transport and tankers under predefined scenarios, covering:
o A scenario for the future market environment (fuel costs, capital, regulatory implications...)
o A scenario for the mission profile (bulk type, port of origin / destination...)

After the delivery of the full design of the first phase ship (Retrofit design), an evaluation of the selected solutions was conducted in order to fully assess the economic aspects, environmental impacts gains that this new design is providing. As well as a complete evaluation of the impact on safety, in order to assess that the new design remains safe to operate.

Unfortunately due to multiple delay during the project, evaluation of Phase II and III was not possible during the course of the project.

Resistance and Propulsion
• A new propulsion performance monitoring system and an engine monitoring system have been specified and designed for tests onboard the reference existing ships (handymax tanker). The target is to be able to monitor propulsion performance and environmental loads under slow steaming conditions. The installation onboard has been initiated, but due to multiple factors, mainly availability and access problems on the ship, it was not possible to complete the installation and measurements during the course of the project.
• Propeller efficiencies for slow steaming have been calculated. One conclusion is that requirements had to be developed to properly design propulsion trains for such slow speeds. A redesign of the existing propeller as well as alternative propulsion concepts are under development. Results show clear potential for large efficiency improvements when designed for slow steaming.
• A preliminary design tool (Excel Spread sheet) for bulk carriers and tankers has been developed. The programme calculates the main dimensions for tankers and bulk carriers based on capacity demand (max. deadweight). The needed engine power is calculated on the basis of speed requirements including requirements for a given sea margin either in per cent and/or based on wind speed such that a head wind situation is taken into account with added resistance due to wind. The amount of each emitted exhaust gas is calculated. Finally the new so-called Energy Efficiency Design Index (EEDI) is also calculated by the computer model.
• An added resistance model (Salvesen, J. Hydronautics, 1978) has been implemented using a strip theory code and calculations have been made for the Phase I ship.
• A desk study was set up for assessing fouling aspects and expected performance of existing fouling control techniques under ultra slow steaming conditions.

Wind Power
• Models for kite propulsion have been developed, a reasonably detailed dynamic model for validation and generation of kite data and a simplified static one, the latter implemented and made useable in a sea keeping time domain simulation tool.
• Reliable validation data for Flettner rotors have been obtained from wind tunnel tests. Simplified models for Flettner rotors and suction sails have been implemented and made useable in the sea keeping time domain simulation tool. Reliable computational procedures for quantifying the full scale performance of Flettner rotors have been developed.
• The ship behaviour and power predictions using the auxiliary wind propulsors have been calculated for the reference ship.
• Optimisation procedures for the weather routing simulations have been developed taking into account best utilisation of wind propulsors. This router will be connected to a complete ship simulation model with the actual drive train and ship characteristics.
• The structural design to accommodate the wind propulsors on existing ships as well as the new 2020 design have been done.
• The scantling of the 2020 ship has been defined and structural optimization studies have been conducted.
Machinery and Equipment
• A review and selection of suitable software tools for the development of advanced engine modelling has been performed. A software tool has been purchased and used to develop advanced models of the engine installed on the reference ship. Validation using original test bed data has been also performed.
• These models have been further exploited to investigate and to compare the fuel consumption and power/load profile of engine at slow speed and ultra-slow speed steaming.
• Specific engine settings have been investigated in order to optimise the performance of the engine at slow speed steaming to reduce the fuel consumption while not compromising the engine’s power/load profile with loads from 10% to 100% being modelled.
• An investigation of the long-term effects of slow and ultra-slow speed steaming on auxiliary ship systems has been carried out. A full inventory of all ship auxiliary systems on-board the reference ship was created from information provided by the ship owner and the manufacturers of individual systems.
• A review of the power systems and possible alternative technologies that can be considered in the design of a new build ship for ultra-slow steaming (2020 ship) has been conducted.
Seakeeping and Manoeuvring
• A captive model test study has been performed to investigate the manoeuvring properties at low speed (0 to 10 kt). Measurements have been used to derive a mathematical model of the rudder.
• Seakeeping simulations have been performed to calculate the acceleration on the deck for various sea states up to 6, as input for the structural integration of wind propulsors.
• Rudder and wind propulsor models have been integrated in a strip theory seakeeping software. Simulations have been performed to assess the influence of kite, rotors and suction sails on seakeeping properties.
• The development of a new 3D seakeeping method that will be later able to account for the influence of larger wind propulsors that will affect ship behaviour, has been conducted. It has been used in Phase II and III for comparison of motion and added resistance that are provided by existing 2D methods.

Project Results:
ULYSSES is involved with slowing down and ship propulsion concepts.
Innovating towards cost competitive operation with equipment, meeting the emerging environmental policies lies within the interest of EU Operators and equipment manufacturers.
This chapter has been covered by Wärtsilä.

Towards exploitation the following knowledge and technologies can be highlighted:

Design process
-Better understanding of environmental factors, in particular quantification of added resistance influenced by speed and hull shape. This is of direct use for ship designers and drive train manufactures.
-Performance based design approach. A 3-iteration approach has been developed, being of value for commercial projects. Basically a first attempt has shown that incorporating simulations and targeting to influence overall ship performances under actual operating scenarios is quite difficult. But possible when introducing a non-standard design process, secure information availability related to performances at an early design stage, introduce a simulation method and learn to cope with the results in terms of implications for the design choices.
-Simulation tools: Drive train simulations, sea keeping & manoeuvring simulations, route simulations and computational flow models are the main simulation tools being valued combined with a shipping cost scenario calculation.
-The measurement system designed is ready for installation and will give us valuable validation feedback and service product possibilities.

-Drive-train products - propellers:
The implication of slowing down is better understood. Best propulsor concepts have been identified. Alternative propulsors and energy saving devices have been investigated for existing and new vessels. The PBCF will be further developed for CPP’s, A pre-duct is under development and a finprop for the 2050 design needs further investigation but looks promising and will reduce the power consumption with around 15% well tuned to slow speed operation and wind propulsion
-Drive-train products - engines:
For the engine in particular related to torque and speed available at low load. Deviating from maximum continuous rating as the main item for engine selection. As well as further tuning possibilities and reliability.

-Drive-train products - wind:
Performance are available, in particular the full-scale effects resulting into much less power + the weather routing enable pre-competitive evaluation to identify commercial applications. Here we are further integrating wind into the drive-train. In particular total fuel saving and load control is to be developed with increase of power fluctuations due to the wind force.

-Ship hull performance
Sea keeping and manoeuvring studies indicate less risk than was expected, rudder is of relevance. The hull improvement results are limited to an improved bow shape, and needs confirmation in terms of total ship resistance improvement.

Design results:
-Phase I: existing ships. At the start, somewhat limited due to the need to develop technologies first. Parallel to phase II, multiple solutions have been identified being applicable for retrofits. In particular: propeller redesigns, pre-ducts and engine tuning. The operational-based return of investment can also be calculated. Engine tuning and route optimisation. The wind assistance we find rather difficult to value on retrofits, maybe as a pilot to learn from.

-Phase II: new drive-train solution, benefiting from smaller engine, hybrid solution for ultra-slow + booster for steaming, together with bringing home mode and reduction of 1 tug when entering port. The wind system has large potential and has to be investigated further.

-Phase III: here we have been able to fully benefit from wind and finprop propulsion. The future concept visions is based on slow steaming, little or no crew on board, wind powered supported by ultra large fin propulsion and de-central power systems. The varieties of energy sources onboard and crew reduction have resulted into a 2050 concept we actually believe in. Also we are interested in further electrical en free-piston developments.

Retrofit knowledge will result into direct utilisation and priority of propulsor product needs.

New build we will further work out and plan to launch this at the Electric& Hybrid conference by University of Newcastle and Wärtsilä. We are currently increasing efforts in suitable e-motor choices and in parallel continue on wind propulsion exploration with Crain.
Side result is that the Technical Coordinator of Ulysses from Wärtsilä, has been invited as keynote speaker at the opening of the Electric & hybrid conference to present: “The benefits of hybrid propulsion and electrification for vessel owners”.

Involving the 2050 concept we will further investigate the finprop, possibly patent the mechanical drive. On the 2-stroke engine we plan to revisit some 16 possible developments long-term and short-term, also identify the added value on total ship level in quantitative numbers.

Wärtsilä is equipment manufacturer multinational with many offices and products. Thanks to Ulysses we have been able to also improve our internal cooperation and understanding strengthening: propulsion R&D and Solution R&D in the Netherlands, 2-stroke R&D and servicing in Winterthur, Ship design in Poland and Germany.
Also we have been able to grow closer to 3 merchant operators, one not (yet) utilising our products, as well as with class BV and DNV-GL, being able to share and cooperate under ULYSSES.

• Generally, participation in ULYSSES allows Universities to increase cooperation with the industry as well as improving knowledge in current technologies.
• DTU:
• Results important for SHOPERA, numerical models improved, PhD funding (end Oct. 2014).
• Increase collaboration with engine manufacturer, possible new collaboration in the future.
• CUT:
• Flettner wind propulsion technology and cooperation, in particular with SSPA and CRAIN

– SEAMAN program developed.
– Improve the models within GES and the corresponding Library of maritime components.
– Collaboration with Newcasle Univ. and Wärtsilä very valuable.
– Routing models developed within the project have a real value for practical applications.
– Better knowledge on wind propulsors, plans to build a demonstrator of suction sails (2015).
Design & Engineering
• As2con
– Experience in Design of a future ship valuable to show to clients.
– Cooperation with knowledge and OEM Wärtsilä.
– Great interests on the findings on energy reduction on board.
– No new building at the moment retrofit (Phase I) more relevant than 2020 (Phase II).
– Results will help to define the next generation of tankers.
• OSG (Advisory Committee)
– Currently looking at every possible solutions to reduce fuel consumption.
– Interested in retrofit.
– Interested in seeing proper benefits to show to senior management. (structural reliability, sailing routes, …)
• GL & BV
– Development of the reliability software.
– Basis for the development of new rules.
– Increase strength/competence in general.
– Manoeuvrability calculations, validation of tools and methods.
• Wärtsilä
– Competitive 2020 new build hybrid solution originating from Ulysses
– Hybrid system usable for a VLCC design case
– Strengthening Retrofit applications
– Further exploitation of engine tuning and adaptations
– 2050 future concept with wind and fin propulsion
– First acquisition of real applications identified during the project
– Enhanced propulsor product & expertise & validation
– Exploring future cooperation with Ulysses project partners
– Further directions towards 2-stroke engine & propulsion solution developments
– Wärtsilä Internal solutions integration and design approach
– Ulysses phase II and III designs launch at Electric& Hybrid conference June 2014
– Possible patents related to finprop mechanical solutions.
– Image and visibility of our work in view of our customers

Impact :
The various partners which actively have contributed to the project outcome have strengthened their respective market position. For Wartsila this supports and benefits the following business areas:
- Propulsor business : propeller solutions to slow steaming and energy saving systems
- 2 stroke engines: slow steaming application and upgrade packages
- Solution business: hybrid concepts, improved system integration approach
- Electric and automation business: hybrid concepts
Dissemination on commercial level will be based on business to business commercial discussions in which the outcome from Ulysses will be utilised as start for investigating offers. This process will start after the closure of the project and be based on selected clients and client interest.

Potential Impact:
Communication and Dissemination
• More information about Ulysses project architecture, partnership and news are available on the project web site:
• The ULYSSES consortium provided support for the summer school at DTU in August 2012.
• A public seminar has been held in Paris on 30th November 2012.
• Publications and presentation have been made during the first half of the project:
o Claudepierre, Martial, Klanac, Alan and Aleström, Björn (2012) Ulysses - the ultra slow ship of the future, Green Ship Technology Conference, Copenhagen, March 27-29, 2012.
o The paper Hongdong Yu, Jonathan Heslop, Rikard Mikalsen, Yaodong Wang, Anthony P. Roskilly (2012) Optimising the operation of a large two-stroke marine engine for slow steaming, Low Carbon Shipping Conference, Newcastle, UK, 11/12 September 2012 has been accepted.
• Several local press articles have also been issued to inform the maritime community about ULYSSES project:
o The Maritime Executive - New Ultra Slow Ships To Reduce Greenhouse Gas Emissions, March 14, 2011.
o Safety4sea - Project says slow ahead is path to cutting CO2 emissions, March 11, 2011.
o Shipbuilding Tribune - European Countries Work on Project ULYSSES to Develop Environmentally Friendly Concept of Ultra Slow Ships, March 15, 2011.
o Press4transport - Full Green Ahead
o Brochure "Staying ahead of the wave" on maritime research under the European Commission`s Framework Programmes

List of Websites: