Extract of Report Risk Cost Benefit Wind Propulsion - 20130614

7/28/2019 Extract of Report Risk Cost Benefit Wind Propulsion - 20130614

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EXTRACT OF DNV REPORT NO. 2009-0634FORPRIVATE USE ONLY

Table of Content Page

1 COST ........................................................................................................................... 1

1.1 Skysails price 1

1.2 Discussion: Wind propulsion and the extra cost of Schedule Integrity 1

2 BENEFIT ..................................................................................................................... 3

2.1 Presentation of the savings calculation tool 3

2.2 Example of utilisation: case study of a shuttle tanker in the Mediterranean

Sea, in collaboration with Fouquet Sacop Maritime 72.3 Discussion on the results 14

3 CONCLUSION ON COST AND BENEFIT............................................................. 15

4 REFERENCES........................................................................................................... 16

4.1 Outlook 16

4.2 Operational safety 17

4.3 Performance modelling and measurement 17

4.4 Performance improvement 18

4.5 Cost Benefit 184.6 Others 18

APPENDIX A: MAIN SOURCE CODE OF SAVING CALCULATION TOOL INMATLAB................................................................................................................... 19


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DET NORSKE VERITAS - REPORTNO:2009-0634, EXTRACT. FORPRIVATE USE ONLY.

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Reference to part of this report which may lead to misinterpretation is not permissible.

1 COST1.1 Skysails priceAt the moment of writing, the Skysails system is available as a pilot product for 160m2 and320m2 kites. A smaller version of 80m2, used as a prototype at the beginning of the developmentof the product, is being adapted to the fishing vessels and super yacht market segment. A larger

version of 600m2 is also in development. Both new products are expected to be ready forcommercialisation in a few years time. The price of the overall system is broken down as inTable 1:

Table 1 Price of the Skysails system as a function of kite size. Source: Fabian Juers, KeyAccount Manager, Skysails.

SKS 160m2

SKS 320m2

Investment costs (in EURO) 420,000 670,000

Yearly fee for maintenance (in EURO) 30,000 to 50,000 30,000 to 60,000

Maximum suitable vessel size (in Dwt) 10,000 20,000The most expensive part of the system is the telescopic mast. The kite itself is the cheapestelement, between 5 000 to 10 000 EURO. The fabric used to make the kite is very sensible toUVs and has to be replaced every 1000 hours approximately.

Skysails recently teamed up with Zeppelin Power Systems to set new worldwide standardsthrough the joint marketing of diesel-wind hybrid power systems. Zeppelin Power Systems

robust sales and service network will ensure that the SkySails-Systems are maintained and

serviced quickly and reliably across the globe. Zeppelin has been the partner of Caterpillar, the

worlds largest independent manufacturer of diesel engines, for over 50 years and is one of the

leading sales and service organizations for marine engines

.

1.2 Discussion: Wind propulsion and the extra cost of Schedule IntegritySchedule Integrity means for the captain to make sure to arrive on time for the loading/unloadingslot at the harbour. If the vessel arrives too late, the ship loses its slot and has to wait for a nextone available, generating a fee for being late and an opportunity cost of several days with only

profit but costs.

As the wind is a parameter the captain cannot control, wind propulsion is often seen as unreliablefor commercial operation. This argument doesnt hold for the following reasons:

The combination of waves, wind and current is not controlled by the captain but hisexperience is here to tell him how to steer his vessel in order to make it on time.

Source: www.skysails.com


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Wind propulsion shall only assist the engine to propel the ship, i.e. the ship will run exactly

at the same speed as it would do without wind assistance. The additional drawing help fromthe wind will result in a lowering of the fuel costs.

1.2.1 Need for routingThe Skysails console on the bridge is linked to a weather station. Depending on the windforecast, it indicates if the kite can be flown or not, and for approximately how long.

A more advanced decision making system would take into account the wind direction andintensity, as well as the ship course and speed, in order to predict what is the potential kite

pulling force and how fast can the ship sail at a reduced speed with the assistance of the kite.

The simulation and monitoring of the behaviour of the ship in waves and advice to the captain onthe speed and course through the waves is commercially available. Such a system could befurther developed to take a kite or any wind technology into account. Research is being carriedout on this topic, see section 0.

It would enable the captain to modulate the speed and course of the vessel throughout all the trip,benefit from the favourable winds and currents, in order to make the destination on time with aperfect control on the fuel consumption of the vessel. The practice is very often to speed up asmuch as possible in the beginning of the trip in order to be sure to make the destination on time,ending the trip with a reduced speed. As the fuel consumption is approximately proportional tothe third power of the speed, this strategy is very much fuel consuming.

1.2.2 Decoupling ship speed and costs: return to normal speedAnother show stopper on wind propulsion is that it is seen as a very slow way to deliver goods.

First, it has to be slow, as the apparent wind created by the ships movement itself is opposite tothe ships course, and shouldnt exceed the true wind. In the case of kite, it is somehow different,as the kite flies in high altitudes and creates its own apparent wind when manoeuvring the kite(in horizontal 8 patterns), generating on average 5 times more wind drag compared to the windconditions on the surface of the sea. But the kite still needs to be launched and for that sake thevessel speed might have to be reduced during the 15 minutes it takes to launch the kite.

Second, the recent downturn in the world economy shows an interesting decoupling betweenship speed and operational costs. It is no longer taboo to operate with very much slower speeds,

balancing the capacity need by adding an extra ship to a service. AP Mller Mrsk is operatingtheir container vessels at speeds as low as 10 to 20% of the engine design load, proving that it is

possible with a close monitoring of the machinery. Wind propulsion could benefit very much tothis slow steaming policy, or return to normal speed, as Wilh. Wilhelmsen puts it*, meaningthat the ships have been operated at an excessively high speed for a long time.Cost Benefit analyses shows actually that the overall cost of operating a fleet (Capital Cost,Operational Cost, Fuel Expenses) has a minimum for a reduced fleet speed and an increased fleetsize, see Ref Cerup-Simonsen and Andersson.

* Source: Knut Arnesen, vice president innovation in WW


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2 BENEFITThe benefit of the Skysails system, as well as any other wind propulsion system, is verydependent on the trade of the vessel and the vessel propulsion system. It is however notdepending on the size of the vessel, as for a trawler or a large tanker, the pulling force of the kiteis the same (as long as there is just one kite per ship)! In proportion to the overall thrust neededto propel the vessel, the kite is obviously more efficient for small vessels.

2.1 Presentation of the savings calculation toolThe purpose of developing a saving calculation tool is to estimate the potential savings (in

power, fuel and CO2) for any ship, trade (that is, route and season, that is, wind statistics!), windpropulsion technology, and operation of the vessel (that is, how the pulling force created by the

wind technology is converted into propulsive energy).

This tool has been developed in MATLAB in collaboration with Jean Gregoire Kherian whowrote his masters thesis at the University of Southampton with the author of the present reporton a kite performance calculation model, Ref Kherian.

2.1.1 Inputs and OutputsThe different input parameters of the simulations are:

The route (also called trade) the ship is sailing on: ship speed and direction (heading).Two loading conditions, for example full load and ballast, can be defined and assigned toa selected part of the route.

! The wind conditions met on this route (speed and direction) associated with a probabilityof occurrence. The wind speed and direction seen on the ship will be different becausethe ship has already its own speed.

! The ship hull, propeller and engine characteristics to express how much energy (power inkW) is needed to move the hull at a certain speed, how this amount of energy can betransmitted by the propeller to the water, and what is the fuel consumption of the enginewhen delivering the required amount of energy.

! The characteristics of the sail used to assist the propulsion of the vessel, in order tocalculate its performance in any wind condition. The sail performance can also bemeasured, for example in a wind tunnel and given in the form of a table giving the liftand drag coefficients of the sail as a function of the wind direction.

The output of the simulations is how much power can be saved by using the assistance of a sailand how does this translate into fuel, CO2 and dollars savings.

2.1.2 Architecture of the saving toolThe architecture of the simulation program is illustrated in Figure 1. The individual modules ofinterest are presented in more details in the following sections.


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Figure 1 Architecture of the savings calculation tool

2.1.3 Sail performance calculation moduleA kite performance model is implemented, based on the model developed at SouthamptonUniversity, Ref Wellicome, Kherian. Different mathematical models have been published to

predict the aerodynamic performance of a kite with various degrees of accuracy, Ref Koster,Naaijen, Williams. The model from Southampton predicts the wind speed seen by the kite as afunction of its position on the wind window. The lift and drag forces of the kite are thencomputed using lift and drag coefficients. Actually only the lift to drag ratio is necessary for thecalculation, typical ratios lying between 5 and 6.The force can be calculated when the kite is static, keeping the same position on the windwindow, or when the kite is manoeuvred across the wind window. The force is then averagedover one manoeuvre as the integral of instantaneous static forces on each point of the trajectory.An optimal trajectory is found between different alternative trajectories. Advanced research is

being carried out on optimal, stable and robust trajectories, see section 0.

Correct the local wind speed anddirection due to the ship speed

Calculation of sail forces at theapparent wind speed and winddirection

Projection of the sail forces in theship direction to obtain the sail thrust

Effect of the additional thrust createdby the sail on the propellerperformance

Wind statistics

Corrected power to be delivered bythe propeller to sail at the desiredspeed

Ship Route

SailCharacteristics

PropellerCharacteristics

Hull

Characteristics

EngineCharacteristics

Savings: fuel,CO2, $

Compare the nominal and sail-reduced power


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2.1.4 Propulsion efficiency calculation moduleThe effect of the additional thrust created by the sail on the propeller performance is fundamentalfor the simulation. When the assistance of a sail is used, the operation of the propeller is shiftedoutside its design point and the efficiency of the propeller is modified, as well as the power to bedelivered by the engine to move the ship at the desired speed.On the MV Beluga Skysails, the propeller rotates at constant RPM to produce the onboard needof electricity through a shaft generator. The power delivered to the water to propel the vessel isadjusted by modifying the pitch of the propeller using a Controllable Pitch Propeller (CPP). Thesimulation of this process is implemented in the saving calculation tool as follows:

1 In normal operation, without kite

Calculate the thrust coefficient KT and advance ratio J of the propeller

KT, no kite = RT/(1-t)/(!*n2*D4);J = VShip*(1-w)/n/D;WithRT = ship total resistance [kN]t = thrust deduction factor [ ]! = water density [tonn.m-3 ]n = RPM [ ]D = propeller diameter [m]VShip = ship speed on the route [m.s

-1]w = wake fraction [ ]

2 Flying the kite, keeping the vessel at the same speed, hence reducing the thrustCalculate the reduced thrust coefficient KT, kiteKT, kite = (RT-Fkite)/(1-t)/( !* n

2*D4);WithFkite = kite pull in the ship direction [kN]

3Finding the new operation point of the propeller:Same advance ratio, new thrust coefficient, what is the new pitch?The new pitch Pkite is interpolated in a table giving the pitch as a function of the advance rationand the thrust coefficient for the calculated J and KT, kite.

This step is illustrated in Figure 2.

4Finding the corresponding torque Qkite at the new pitch Pkite and reduced thrustKT, kiteUsing a table giving the torque coefficient KQ, kite as a function of the pitch and advance ratio, forthe calculated J and Pkite in order to calculate the new torque Qkite :Qkite = KQ, kite * ! *n

2*D5;

5 Finding the new brake power PB, kite derived from the new torque:PB, kite = 2*"*n* Qkite /#S;With#S = shaft efficiency, typically 95%.


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Figure 2 Propulsion module: shift of the CPP operation point when flying the kite: same

advance number J, but different pitch P, leading to a different thrust coefficient KT

On board of the ship, this procedure is automated. The result is the same as driving a car with a

cruise control option with wind blowing from the back or going downhill: the power demandis adjusted to cope with the assistance of the wind or the favourable slope, maintaining the speedof the car constant.

2.1.5 Short term and Long term calculationsThe wind statistics are imported from the database ARGOSS* as a table of probability ofoccurrence of a certain wind speed and direction, similar to a wave scatter diagram. The kiteforce is calculated for each cell of the table, that is, for each combination of wind speed anddirection, once the correction due to the ship speed and direction is applied.

Short term statistics refer in this case to savings calculations based on the most probable windspeed for the most probable wind direction. The wind direction with the highest probability ofoccurrence is selected first. In this wind direction, the wind speed occurring most often isselected.

Long term statistics refer to savings calculation for all wind directions and speed, weighted bythe probability of occurrence of each combination of wind direction and speed.

2.1.6 Expression of savingsThe savings are always expressed as:

% saving = (value without sail value with sail) / value without sail

The saving calculation is applied to the thrust and torque coefficients, the brake power, and the

fuel consumption.

*www.waveclimate.com

J

KT, kite

@PitchPno kite

J

@PitchPkite

KT, no kite


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The translation into CO2 emissions has not been implemented. The quantity of CO2 emitted is

approximately 3 times the quantity of fuel consumed, Ref IPCC.

The fuel consumption depends on the make of the engine and the brake power.

2.1.7 Generalised use of the saving tool to other wind technologiesThe saving tool has been developed with the kite example in mind, but with the aim to be usedfor any other type of wind assisting technology. In the previous sections, kite can besubstituted with sail, applying the same principles of saving calculations. The only input tochange is the sail performance module. It consists in a table giving the sail thrust (resultingaerodynamic sail force projected in the ship direction) as a function of the apparent wind speedand direction. The contours of this table are plotted in Figure 3, taking the example of a 80 m2

kite with a lift to drag ratio of 5:

Figure 3 Kite performance as a function of relative wind speed and relative wind direction.

The kite performance is given by the horizontal pull force exerted by the kite in direction

of ships movement. Wind direction and speed is given relative to ship movement and speed.

Calculation for a static kite with an area of 80m2

and a lift to drag ratio of 5.

2.2 Example of utilisation: case study of a shuttle tanker in theMediterranean Sea, in collaboration with Fouquet Sacop Maritime

Several DNV customers were contacted through the local Customer Service Managers in France,Germany, Denmark, Japan and Norway. Fouquet Sacop Maritime was selected for the regulartrade of their shuttle tankers in the Mediterranean Sea and the enthusiasm of CommandantMichel Ailliot, master of the FS Solene, who has been trying since the 1990s to retrofit a kite toany floating object!

2.2.1 InputsFS Solene is a 5820 DWT Tanker with the following dimensions:


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Table 2 Main particulars of FS Solene

Length Overall 105.50 m

Length Between Perpendiculars 99.35 m

Beam 16.80 m

Depth 7.40 m

Contract speed 11 knots

Like MS Beluga Skysails, FS Solene is operating a CPP at constant RPM to power a shaftgenerator. The pitch table as a function of thrust coefficient and advance ratio, as well as thetorque table as a function of pitch and advance ratio have been kindly provided by Ege Lundgrenfrom MAN Diesel, designer of the propeller*.

Figure 4 FS Solene in Ballast

FS Solene sails round trips between Corsica (Bastia) and Malta (Valeta), as illustrated in Figure5:

* [email protected]


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Figure 5 Trade of FS Solene between Bastia and Valeta, ca 500 nm one way

The Ship is on full loading condition in one way and in ballast condition on the other.

The resistance of the vessel is calculated for both loading conditions using the Holtrop method,Ref Holtrop. The kite characteristics used for the calculation are given in Table 3

Table 3 Kite characteristics used for the calculation

Cable length 200 m

Kite area 80 m

2

Lift to Drag Ratio 5 -

Kite flight Static -

The performance of the kite is dependent on all these input parameter. The values used for thecalculation are based on those used on board the MV Beluga Skysails. For discussions on theinfluence of kite length, area, lift to drag ratio and type of flight, see Ref Kherian, Koster,

Naaijen and Ilzhofer.

2.2.2 OutputsThe calculation is performed for four different seasons in a year, associated with four different

wind statistics: Wind, Spring, Summer, and Fall. The different outputs are presented in Figure 6to Figure 11.


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Figure 6 Force saving: comparison of the FS Solene total resistance (in full load

condition) with the force generated by the kite in static flight. The average pulling force

from a kite counter act only 1.25% of the total resistance with long term statistics

The pulling force of a small kite operated in static condition can seem very little, compared tothe overall resistance of the vessel. However, the additional pull created by the kite reduces the

load on the propeller leading to increased propulsion efficiency, see Figure 7. The ratio betweenthe kites pulling force and the total resistance of the vessel can however not be used as anindicator of the potential fuel savings.

Figure 7 Thrust saving: comparison between the propeller thrust coefficient when the

kite is in operation (in blue Short Term and green Long Term) and when the kite is


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not in operation (in red No Kite Thrust). The averaged saving is 6.15% with long term

statistics

The thrust coefficient of the propeller indicates how much thrust needs to be generated by thepropeller to move the vessel at a desired speed. When the kite is in operation, it unloads thepropeller reducing the need for thrust, while maintaining the vessel speed.

The ratio between the kite pulling force and the ship total resistance depends on the design of theship hull. Whereas the thrust coefficient depends on the design of the propeller and the additionalkite force. These two ratios are different, which explains the difference of force saving inFigure 6 and thrust saving in Figure 7.

Figure 8 Torque saving: comparison of the propeller torque coefficient when the kite is

in operation (in blue Short Term and green Long Term) and when the kite is not in

operation (in red No Kite Torque). The averaged saving is 6.66% with long term

statistics

The torque coefficient of the propeller is an indicator of how much power needs to betransmitted by the propeller to the water to move the vessel at a the desired speed. When the kiteis in operation, it unloads the propeller reducing the required torque to maintaining the vesselspeed.

The torque and thrust characteristics of a propeller are both dependant on the propeller designbut not necessarily linearly linked, so that the thrust saving and the torque savings are notidentical either, as shown in Figure 10 and Figure 11.


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Figure 9 Power saving: comparison of the engine brake power when the kite is in

operation (in blue Short Term and green Long Term) and when the kite is not in

operation (in red No Kite Torque). The averaged saving is 6.51% with long term

statistics

Reducting the required thrust and torque leads to a reduction in the power delivered by theengine to move the vessel at the desired speed, called engine brake power. The difference

between torque saving and power saving comes from the efficiency losses at the propellershaft, as shown in Figure 10and Figure 11. A value of 5% efficiency loss is assumed in this case.

Figure 10 Comparison of the Thrust, Torque Power and Fuel savings in the case of Short

Term statistics


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The savings in engine power and fuel are identical, as the fuel consumption has a very little

variation with respect to the engine brake power.

There is a little seasonal variation in the Mediterranean Sea, compared to what one could expectin the North Atlantic.

Figure 11 Comparison of the Thrust, Torque Power and Fuel savings in the case of LongTerm statistics

The short term statistics represent the case when the kite is flown at the most probable windspeed and wind direction of the area where the ship is sailing. This condition will be optimal ifthe angle between the most probable wind direction and the ship course lies in the range wherethe kite pulling force is optimal.

The long term statistics represent the case when the kite is flown in any wind condition presentin the area where the ship is sailing. The kite pulling force will be zero when the relative windcondition are out of the limits where the kite can be flown. When the wind conditions arefavourable (ie within the flying limits), every contribution will be taken into account into theaverage kite pulling force calculation, as described in section 2.1.5.

The favourable wind conditions as defined by Skysails are between Beaufort 4 and 8, with thewind coming as close as 50 degrees to the sailing direction of the ship, as shown in Figure 12. In

practice, it has been found out by Skysails that 70 degrees into the wind is the closest the kite canget into the wind, and the optimal angle are between 120 and 140 degrees to the wind.


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Figure 12 Flying conditions as defined by Skysails. Source: Skysails.

In this case study, the long term savings are slightly larger than the short term statistics, but itcould be different for another configuration of predominant wind direction and ship course.

Already with a small kite operated in static condition, the power and fuel savings can reach 6.5%

in average through the year. A larger kite (160m2 for example) operated in dynamic flight couldreasonably reach 15-30% fuel savings. The dynamic operation of the kite can reasonablyincrease the apparent wind seen by the kite with a factor 2, which in turn can create a pullingforce 4 times larger, as the aerodynamic force of the kite depends on the square of the apparentwind speed. The effect of Dynamic operation is documented in Ref Dadd, Kherian and Naaijen.

2.3 Discussion on the resultsThis calculation method is a statistical method aiming at comparing different wind technologies,on different trades, for a cost benefit analysis, on the same principle as Ref Smulders. Severalassumptions are made, based on results of existing research, summed up in Table 4.

Table 4 Assumptions used in the calculation. Justification and reference.

Assumption Justification Reference

Static operation of the kite Dynamic model not validated Dadd, Kherian

Straight ship course Practice on board Commandant Alliot of FSSolene

Constant speed As much as possible, exceptunder the 3 miles limit

Commandant Aillot of FSSolene

No side force Has a negligible effect Naaijen


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No effect of waves on kite

performance

Has a negligible effect Kherian

No effect of waves on shipresistance

Outside the level of details forthis project

No research taking intoaccound added resistance inwaves so far. In futureresearch plans of Naaijen

Kite has zero mass (inSouthampton model)

Zero mass model comparesfavourably to a lump massmodel and experimentalmeasurement.

Dadd

Further improvement of the calculation tool is always possible. The architecture of the toolmakes it possible to improve independently any module (sail performance, propulsion

performance, savings calculation).

The assistance of sail on a ship has a non negligible effect on the operation of the vessel. The sailcan be seen as an extension of the sea margin, allowing to reduce the power on board the vessel.Similarly to slow steaming, operating at a reduced %MCR creates the need to monitor thecondition of the different mechanical pieces of the machinery plant, for example the TurboChargers.

3 CONCLUSION ON COST AND BENEFITIs this calculated 6.5% fuel saving enough to cover the kite expenditures? What is the break evenpoint in % of fuel reduction and in fuel price?

Three different scenario based on the case of the shuttle tanker sailing in the Mediterranean Seawith a 80 m2 kite are presented in Table 5 Simple Cost Benefit Calculation: oil price and % offuel savings required for a pay back period of 4 years with a kite of 80m2to answer this question.

Table 5 Simple Cost Benefit Calculation: oil price and % of fuel savings required for a pay

back period of 4 years with a kite of 80m2

Unit Scenario A Scenario B Scenario Cdaily fuel consumption* Metric

Tonne10 10 10

number of days/ year - 146 146 146

price of fuel oil

(MDO IFO 380)

$ 300 500 1150

annual fuel cost $ 438000 730000 1679000

* Estimation based on use of the main engine at 75% of the MCR of 2720 kW with a specific fuel oil consumption of 200g/kWh,as given in the engine documentation

According to Fouquet Sacop Marine, the engine has been run 19 000 hours in the last 5 years, giving a rate of use of 43%,corresponding to 146 days of sailing per year (when rounded to a 40% rate of use)


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% annual fuel savings % 24 14,5 6.5

annual fuel saving $ 105120 105850 109135

Pay back period* year 4 4 4

Scenario A is with an oil price as of April 2009 (300$ per metric tonne). Under 24% of fuelsavings, the kite system is not profitable for the shuttle tanker sailing in the Mediterranean.

Scenario B is with an oil price as of April 2008 (500$ per metric tonne). In these conditions,wind propulsion is more interesting, and fuel savings of 14.5% are enough to make the system

profitable. As mentioned in section 2.2.2, such savings can be achieved with a larger kite flowndynamically.

Scenario C is with an imaginary oil price of 1150$ per metric tonne that could possibly happenwithin the next decade if one believes the peak oil theory, which says that the world wide oilreserves are not sufficient to cover the energy needs of the human activity, leading to a drasticincrease of oil price in a near future. In these conditions, the system is profitable with fuelsavings of only 6.5%.

By profitable is meant here under 4 years of payback period. The investment cost is theobvious dominating factor and could be reduced by extending the investment horizon.

The cost will increase if a human operator is needed to monitor constantly the kite. It is a veryimportant argument that the whole kite system must be fully automated AND extended to alsonight flying, which is not the case at the moment of writing this report, this is where DNV could

offer a valuable help!The first Atlantic crossings of the MV Beluga Skysails on a route following the trade winds(westbound from Europe to South America, eastbound from the north east coast of the UnitedStates to Norway), reported power savings up to 20%, with a yearly average between 10 and15% in may 2008, RefIMO-GHG WG. Note that at the moment the kite is not used at night.More recent figures from the GreenShip Technology Conference in Hamburg in end of march2009 reported power savings up to 30%, with a yearly average of 17%. The target of Beluga is tosave 2000$ a day with the kite.

Compared to other emission reduction measures, the kites are considered as a cost effectivesolution, according to the CATCH Index (Cost of Averting in Tonne of Carbon Heating gas)

used in Ref Longva and Eide.

4 REFERENCES4.1 Outlook

Nance, C.T, Outlook for wind assistance, Journal of Wind Engineering and IndustrialAerodynamics, Volume 19, Issues 1-3, pp. 1-17, 1985

* Based on the following price of a 80 m2 kite: 300 000 $ investment, 30 000 $ fee per year (respectively 240 000 and 24 000euros with a conversion rate of 1 USD = 0.8 EUR)


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Wellicome J.F, Some comments on the relative merits of various wind propulsion devices,

Proceedings of the International Symposium on Windship Technology (Wind Tech 85),Southampton, U.K., April 24-25, 1985. V4b. 111 - 143

ORourke Ronald,Navy Ship Propulsion Technologies: options for reducing Oil Use Background for Congress, CRS Report for Congress, December 2006

Clauss G.F, Simulation of the Operation of Wind-Assisted Cargo Ships, TU Berlin, 2007. (InGerman)

MEPC GHG WG 2 WP 1Draft guidance on the Development of a Ship efficiency ManagementPlan (SEMP), paragraph 1.4.39 Even wind assisted propulsion may be worthy ofconsideration, 2009.

4.2 Operational safetyWagner H.G, Ships with Main Propulsion by Sail: General and main requirement for Reefing ofSails and Turning of Masts, DNV Technical Report 81 -0687, 1981.

Brett, P.O,Principles of safe design of sail driven merchant vessels, DNV

Research Paper 81-P084, 1984.

4.3 Performance modelling and measurementKherian, J.G,Kite force prediction for ship propulsion, University of Southampton, Ship Sciencedepartment, MSc report , 2006

Gernez E,Experimental and Numerical Investigation of the Performance of a Kite, University ofSouthampton, Ship Science department, MSc report, 2006

Naaijen P, On the power savings by an auxiliary kite propulsion system, InternationalShipbuilding Progress 53 (2006) 255279, 2006

Koster V, On the power savings by an auxiliary kite propulsion system, Master Thesis, Delft

university, 2006Dadd G.M,Development, Validation and Demonstration of a Test Rig for Kite Performance,University of Southampton, Ship Science department, MSc report, 2005.

Dadd G.M, A Comparison of two kite force models with experiment, University ofSouthampton, Ship Science department, 2009.

Williams P, Optimal Crosswind Towing and Power Generation with Tethered Kites, DelftUniversity of Technology, 2007

Fujiwara T, Steady sailing performance of a hybrid-sail assisted bulk carrier, Journal of MarineScience and Technology, nr10, p13146, National Maritime Research Institute (NMRI), Japan,

2005


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4.4 Performance improvementIlzhofer A, Optimization of a Kite Boat, Interdisciplinary Center for Scientific Computing, 2008

Hagiwara H, Weather Routing of (Sail Assisted) Motor Vessels, Phd Thesis, University of Delft,1989.

Naaijen P,An Estimation tool of long term benefits of auxiliar wind propulsion by means of atraction kite including the effect of route optimization, University of Delft, 2009

Andersson, L,Economies of scale with ultra large container vessels, MBA assignment no 3, TheBlue MBA, Copenhagen Business School, 2008.

Cerup-Simonsen, B,Effects of energy cost and environmental demands on future shipping markets,

MBA assignment no 3, The Blue MBA, Copenhagen Business School, 2008.

4.5 Cost BenefitStavdal, T,A Feasibility Study on Kite Technology, MSc Thesis in Maritime Economics andLogistics, Erasmus University Rotterdam, 2007.

Smulders, F,Exposition of calculation methods to analyse wind propulsion on cargo ships,Windship technology Proceedings of the International Symposium on Windship Technology(WINDTECH85), Southampton, April 23-25, 1985

4.6

OthersHoltrop, J., Mennen, G.G.J,An Approximate Power prediction Method,International Shipbuilding Progress, Vol.29, No. 335, July 1982

Holtrop, J.,A Statistical Re-Analysis of Resistance and Propulsion Data,International Shipbuilding Progress, Vol.31, No. 363, Nov 1984

IPCC, 2006 IPCC Guidelines for National Greenhouse Gas Inventories, National Greenhouse Gas

Inventories Programme, 2006

IMO-GHG WG, Information related to a system to reduce fuel consumption by using wind power,

Submitted by Germany, May 2008

Longva T, A cost-benefit approach to determining a required CO2 index for future ship designs,

Submitted to Environmental Science and Policy, December 2008.

Eide M, Cost-effectiveness assessment of CO2 reducing measures in shipping, DNV Researchand Innovation, December 2008.

Recommended Practice DNV-RP-A203, Qualification Procedures for New Technology, DNVEnergy, September 2001


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APPENDIX A: MAIN SOURCE CODE OF SAVINGCALCULATION TOOL IN MATLAB

The MATLAB code has been developed by Etienne Gernez and Jean Gregoire Kherian (GustoMC), based on Ref Kherian and Wellicome. Following is the MAIN function of calculation ofthe tool. It shows the example of the case study presented in section 2.2. The rest of the code isin the project folder 359DA019.

%% MAIN% Example of calculation for FS Solene% with route Bastia --> Malta (Full load) and Malta --> Bastia (Ballast)% The route is crossing two different wind statistics zones% The calculations are repeated for 4 different seasons associated with 4different wind statistics%% Seasons: load input and calculate savings for each seasonSeasons=['Winter'; 'Spring'; 'Sommer'; 'Fall '];Seasons=cellstr(Seasons);NSeasons=length(Seasons);Routes=[];% Repeat following calculation procedure for each season.for i=1:NSeasons

%% Load regular input: sail, route, shipKite = Create_KiteStructure('Type','Kitemaran');

RouteFile='RouteBastiaMaltaBastia.txt';Route = Read_RouteInput(RouteFile);Route.IDString = char(Seasons(i));SoleneFull = 'HullSoleneFull.txt';ShipFull = Read_ShipInput(SoleneFull);ShipFull =Read_PropellerInput(ShipFull,'PropellerSolenePD.txt','PropellerSoleneKQ.txt','PropellerSoleneKT.txt');SoleneBallast = 'HullSoleneBallast.txt';ShipBallast = Read_ShipInput(SoleneBallast);ShipBallast =Read_PropellerInput(ShipBallast, 'PropellerSolenePD.txt','PropellerSoleneKQ.txt','PropellerSoleneKT.txt');

% Manual inputShipFull.Propeller.RPM = 166/60; %in rotation per secondShipFull.Propeller.Diameter = 3.6;ShipFull.Efficiency.Shaft=0.99;ShipFull.Efficiency.RelativeRotative=0.99;ShipFull.Engine.LoadMCR=[30 50 75 90 100]; %Engine load (% MCR) whereSpecific Fuel Consumption data is availableShipFull.Engine.SFOC=[200 199.9 195.6 198.7 199.4]; % Specific FuelConsumption in g/kW at different engine loadShipFull.Engine.MCR = 2720;ShipBallast.Propeller.RPM = 166/60; %in rotation per secondShipBallast.Propeller.Diameter = 3.6;ShipBallast.Efficiency.Shaft=0.99;ShipBallast.Efficiency.RelativeRotative=0.99;


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ShipBallast.Engine.LoadMCR=[30 50 75 90 100]; %Engine load (% MCR) where

Specific Fuel Consumption data is availableShipBallast.Engine.SFOC=[200 199.9 195.6 198.7 199.4]; % Specific FuelConsumption in g/kW at different engine loadShipBallast.Engine.MCR = 2720;

%% Load seasonal input: windscatterWindFile1=strcat('Wind/WindBastia', Seasons(i), '.txt');WindFile2=strcat('Wind/WindMalta', Seasons(i), '.txt');WindFile1=char(WindFile1);WindFile2=char(WindFile2);WindZone1 = Read_WindInput(WindFile1);WindZone2 = Read_WindInput(WindFile2);%% Assemble route according to operating profile and wind statistics

Full = [1 2 3]; % indices of route legs when ship is in Full Load. Note thatthe speed is already ajusted in the route input file!Ballast =[4 5 6]; % indices of legs when ship is in BallastZone1 = [1 6]; % indices of legs when ship is sailing in Zone1Zone2 = [2 3 4 5]; % indices of legs when ship is sailing in Zone2for i=1:length(Full)Route.Leg(Full(i)).Loading='Full';endfor j=1:length(Ballast)Route.Leg(Ballast(j)).Loading= 'Ballast';endfor k=1:length(Zone1)Route.Leg(Zone1(k)).WindScatter=WindZone1;

endfor l=1:length(Zone2)Route.Leg(Zone2(l)).WindScatter=WindZone2; end%%% Calculationswarning offallOperation='Constant_Speed';Route = Calculate_SailForceOnRoute(Route,Kite);Route =Calculate_SailPowerOnRoute(Route,ShipFull,ShipBallast, 'TypePropeller','CPP','TypeOperation',Operation);Route = Calculate_PowerSaving(Route, ShipFull,ShipBallast, 'TypePropeller','CPP');

Route = Calculate_FuelSaving(Route, ShipFull,ShipBallast, 'TypePropeller','CPP','TypeOperation',Operation);Routes=[Routes Route];end

%% Store the calculation for all seasons in one Result structureResult.Kite = Kite;Result.ShipFull = ShipFull;Result.ShipBallast = ShipBallast;Result.Routes= Routes;ResultConstantSpeed=Result;%% Post Process

Plot_Saving(Seasons,Result)- o0o -

Documents

Extract of Report Risk Cost Benefit Wind Propulsion - 20130614