Calorific Value of HFO and MDO Comparison Report

7/29/2019 Calorific Value of HFO and MDO Comparison Report

1/17

Our Reference

2004/0036

Date

17. September 2005(revised edition)

On behalf of

Thermo King Corp.314 West 90th StreetMinneapolis, MN 55420-3693

Clients Reference

Titel

Determination of energy cost

of electrical energyon board sea-going vessels

by

Dr.-Ing. Yves Wild

Expert Opinion

Location of the company: Hamburg

Registered at Amtsgericht

Hamburg HR B Nr. 53854

Managing Director: Dr.-Ing. Yves Wild

File: Y:\GMBH\2004-0036 Energy Cost\05-09-17 2004-0036 Report.doc

Bank account:

Deutsche Bank Hamburg

BLZ: 200 700 24

Account no.: 6429716 00

Financial Authority Hamburg-Altona

Tax no.: 02/895/05008

VAT ID no.: DE 158 712 034

Address: Elbchaussee 1

D-22765 Hamburg

Germany

Refrigeration Engineering Consultancy

Marine Engineering Expert Opinions

System Engineering Measurements

W i l dIngenieurbro GmbH

Dr.-Ing. Yves

Telephone: +49 40 390 70 65Mobile: +49 172 410 18 26

Fax: +49 40 390 24 75

Email: [email protected]

Web: www.DrWi ld.de


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Ref.-Nr.: 2004/0036Client: Thermo King Corp.Titel: Determination of energy cost of electrical energy on board sea-going vessels W i l d

Ingenieurbro GmbH

Dr.-Ing. Yves

File: Y:\GMBH\2004-0036 Energy Cost\05-09-17 2004-0036 Report.doc

Content

1 Scope of this report ..........................................................................................1

2 Introduction .....................................................................................................13 Cost factors to be considered............................................................................2

3.1 Fuel oil consumption .................................................................................23.1.1 Nominal fuel oil consumption .............................................................3

3.1.1.1 Theoretical background ...............................................................33.1.2 Effective fuel oil consumption (example)...............................................63.1.3 Development of bunker oil prices ........................................................7

3.2 Lub oil consumption ................................................................................103.2.1 Nominal lub oil consumption ............................................................103.2.2 Effective lub oil consumption (example)..............................................11

3.2.3 Lub oil prices....................................................................................113.3 Efficiency of alternator .............................................................................114 Cost calculation .............................................................................................125 Summary.......................................................................................................14


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File Y:\GMBH\2004-0036 Energy Cost\05-09-17 2004-0036 Report.doc Page 1

1 Scope of this report

This report is given on behalf ofThermo King Corp.314 West 90th StreetMinneapolis, MN 55420-3693

The following question shall be answered by an independent expert:

- What is the cost per kWh electrical energy on board sea-going vessels?

The undersigned has been contacted by Mr. Steve Bryant (Thermo King USA) and Mr.

Dermott Crombie (Thermo King Europe) in October 2004 in order to discuss the scope

of the evaluation. During the Intermodal Exhibition 2004 in Copenhagen the issuing

of a formal report has been requested.

A first edition of this report has been issued in February 2005. Due to the significant

increase of bunker prices during 2005 a revised edition has been issued in September

taking into consideration the current price levels.

2 IntroductionOn board of sea-going vessels the electrical energy has to be produced by on-board

alternators. These alternators are mainly driven by diesel engines or by a PTO (Power

Take Off) from the propeller shaft. Sometimes also other energy sources are used by

installing for example exhaust gas turbines or steam turbines (the steam being

produced with exhaust gas heat). However, the vast majority of vessels is equipped

with diesel generators only.

The following investigation therefore only considers electrical power generation bymedium-speed 4-stroke diesel engines or slow-speed 2-stroke diesel engines (main

engine) with shaft generator.

On modern container vessels the vessels internal power demand is approx. 600 kW

to 1,200 kW depending on the ships size. The main consumers are pumps, fans and

A/C systems. Beside this internal power demand the power consumption of reefer

containers has a significant impact on the overall power consumption. For example

the Monte-class vessels of Hamburg-Sd (built 2004 / 2005 at Daewoo) are


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equipped with 1,365 plugs for reefer containers and have an installed diesel

generator capacity of approx. 15 MW.

Thermo King as an important manufacturer of refrigeration aggregates for reefer

containers claims to offer significant energy savings with their MAGNUM unit in

comparison to competitors products. In order to determine the cost savings that go

along with the energy savings this study here shall determine the specific cost for the

electrical energy on board of ships.

3 Cost factors to be considered

The cost for the electrical power generation can be divided into the direct cost(consumables) and the indirect cost (investment, maintenance).

Investment cost are not taken into consideration in this study because it is difficult to

determine any savings that might be achievable by the installation of smaller diesel

generators in case of having a fleet of low power consumption reefer containers.

Maintenance cost is also not taken into consideration because here, too, it is difficult to

determine any savings if the power consumption of reefer containers is reduced. It

sometimes even might be worse to run diesel engines at lower load thus resulting inhigher maintenance needs.

Therefore only the direct operating cost that are caused by the consumables

fuel oil

and

lubrication oil.

are analysed in this study.

3.1 Fuel oil consumption

Fuel oil consumption has the greatest impact on operating cost of diesel generators.

Therefore the fuel oil consumption of diesel engines will be addressed in more detail

below.


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3.1.1 Nominal fuel oil consumption

3.1.1.1 Theoretical background

Heat of combustion, specific energy or calorific value, is a measure of the energy

content of the fuel. It decreases as density, sulphur, water and ash content increase.

Specific Energy is not controlled in the manufacture of fuel except in a secondary

manner by the specification of other properties.

The energy that is stored in fuels is expressed by the calorific value. When burning

mineral oils not only CO2 is produced but also water vapour. The net calorific value

only specifies the energy that can be used without the condensation heat of this water

vapour. It is therefore applicable for diesel engines. In modern house-hold boilers also

the water is condensed so that in this case the gross calorific value is used.

Net specific energy can be calculated with a degree of accuracy acceptable for normal

purposes from the equation

[ ] )449.2240.9(01.0)(01.01)10167.310802.8704.46( 326 wssawQn ++++=

[MJ/kg]1

with = the density at 15 C [kg/m]

w = the water content [mass-%]

a = the ash content [mass-%]

s = the sulphur content [mass-%]

The net calorific value of marine diesel oil (MDO) and marine gas oil (MGO) is

42,700 kJ/kg, for intermediate fuel oils (IFO) and heavy fuel oils (HFO) it is approx. in

the range from 39,000 to 41,000 kJ/kg. An average of 40,000 kJ/kg can be assumed

for IFOs / HFOs thus resulting in an increase of the specific fuel consumption of

6.75 % in comparison to MDO.

When burning fuel in a diesel engine the thermal efficiency determines the amount of

mechanical energy at the shaft of the engine in relation to the energy in the fuel. Table

1 shows the calculation of the specific fuel consumption. Modern slow-speed 2-stroke

diesel engines as used as main engines on todays cargo vessels reach a specific fuel

1 See ISO 8217:1996 Annex A - Informative


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consumption of approx. 165 g/kWh (when running on MDO) which is equivalent of a

thermal efficiency of slightly more than 50 %. Medium-speed 4-stroke engines as used

as diesel generators on board of vessels can reach a thermal efficiency of up to 45 %(or approx. 185 g/kWh). High-speed 4-stroke engines (like often used in mobile

power packs) only reach approx. 220 250 g/kWh or approx. 35 40 % thermal

efficiency.

Specific fuel consumption per mechnical kWh (at motor shaft)

168,6 gr/kWh 25% 30% 35% 40% 45% 50% 55% 60%

42.700 kJ/kgK 337,2 gr/ kWh 281,0 gr/ kWh 240,9 gr/ kWh 210,8 gr/ kWh 187,4 gr/ kWh 168,6 gr/ kWh 153,3 gr/ kWh 140,5 gr/ kWh








39.000 kJ/kgK 369,2 gr/ kWh 307,7 gr/ kWh 263,7 gr/ kWh 230,8 gr/ kWh 205,1 gr/ kWh 184,6 gr/ kWh 167,8 gr/ kWh 153,8 gr/ kWhNetcalorificvalueo

fthefuel

Thermal efficiency of diesel engine

Table 1: Specific fuel consumption per mechanical kWh depending on the thermal efficiency of theengine and the net calorific value of the fuelSpecific fuel consumption per electrical kWh (at generator output)

177,5 gr/kWh 25% 30% 35% 40% 45% 50% 55% 60%

42.700 kJ/kgK 355,0 gr/kWh 295,8 gr/kWh 253,6 gr/kW h 221,9 gr/kW h 197,2 gr/kWh 177,5 gr/kWh 161,4 gr/kWh 147,9 gr/kWh









Thermal efficiency of diesel engine

Netcalorificvalueofthefuel

Table 2: Specific fuel consumption per electrical kWh (at 95 % alternator efficiency) depending onthe thermal efficiency of the engine and the net calorific value of the fuelUnder part-load condition the specific fuel consumption is increasing significantly. This

increase is higher when operating as generator (constant speed) than as propulsion

engine (propeller curve) (see Fig. 1).

Fig. 2 shows the influence of the engine speed on the specific fuel consumption. In

general the lowest specific fuel consumption is reached at approx. 85 90 % load and

at low engine speed.


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Fig. 1: Specific fuel consumption on the generator and the propeller curve2

Fig. 2: Specific fuel consumption on the generator curve at different speeds3Since diesel generators mainly operate in part load condition the real average fuel

consumption is more than the nominal fuel consumption as specified by the engine

manufacturers.

2 Source: Illies, Kurt: Handbuch der Schiffsbetriebstechnik, 2. Edition 1984, page 6003 Source: Illies, Kurt: Handbuch der Schiffsbetriebstechnik, 2. Edition 1984, page 600

Load

Generator curve(constant speed)

Propeller curve(variable speed)


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3.1.2 Effective fuel oil consumption (example)

In order to determine the real life fuel consumption of auxiliary diesel generators on-

board data of a 2,000 TEU container vessel (built 1992) has been analysed. This

vessel has been chosen because the diesel generators were running on MDO (Marine

Diesel Oil) with a separate fuel oil counter for the auxiliary diesel engines. Furthermore

there have been kWh-counters installed for each generator measuring the produced

electrical energy. Based on this information the average fuel consumption per

(electrical) kWh has been calculated.

The auxiliary engine data has been:

Diesel Generator #1 + #3:

Engine type: MAN B&W 7L28/32

Nominal electrical power: 1,292 kW @ 720 rpm / 60 Hz

Diesel Generator #2:

Engine type: MAN B&W 5L28/32

Nominal electrical power: 928 kW @ 720 rpm / 60 Hz

92 NB 94 NB 95 NB 99 NB 100 NB 101 NB 102 NB Average

Start 25.07.2003 12:00 18.10.2003 12:00 29.11.2003 12:00 18.05.2004 12:00 27.06.2004 12:00 06.08.2004 12:00 18.09.2004 12:00

End 05.08.2003 12:00 29.10.2003 12:00 10.12.2003 12:00 27.05.2004 12:00 09.07.2004 12:00 18.08.2004 12:00 29.09.2004 12:00

Hours time diff. -3 h -3 h -2 h -4 h -4 h -4 h -4 h

Total hours 261 h 261 h 262 h 212 h 284 h 284 h 260 h

kWh Start 19.150.700 kWh 19.949.900 kWh 20.156.000 kWh 21.375.800 kWh 21.683.800 kWh 22.049.800 kWh 22.463.300 kWh

kWh End 19.343.900 kWh 20.008.600 kWh 20.330.200 kWh 21.421.000 kWh 21.803.800 kWh 22.221.100 kWh 22.610.300 kWh

kWh Generated 193.200 kWh 58.700 kWh 174.200 kWh 45.200 kWh 120.000 kWh 171.300 kWh 147.000 kWh







kWh Total 272.000 kWh 310.900 kWh 469.600 kWh 171.800 kWh 319.900 kWh 338.200 kWh 291.700 kWh 2.174.100 kWh

MDO used 60,4 t 70,8 t 120,5 t 43,1 t 85,8 t 81,8 t 68,0 t 530,4 t

specific fuelconsumption

222,1 g/kWh 227,7 g/kWh 256,6 g/kWh 250,9 g/kWh 268,2 g/kWh 241,9 g/kWh 233,1 g/kWh 244,0 g/kWh

Diesel

generator#3

Analysis

Voyagedata

Voyages

Diesel

generator#1

Die

sel

genera

tor#2

Table 3: Determination of the average fuel consumption per (electrical) kWh from on-board data ofa 2,000 TEU container vessel


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Table 3 shows the analysis of the on-board data for seven northbound voyages (with

reefer containers on board) and the calculated specific fuel consumption. The specific

fuel oil consumption varied from 221.1 g/kWh to 268.2 g/kWh. The average valuewas 244.0 g/kWh. The measured value is therefore about 25 % higher than the value

specified by the engines manufacturer (185 g/kWh mechanical or ~190 g/kWh

electrical). The higher consumption can be explained by the low average load of the

engines (when running) which was only between 42.8 % and 48.7 % instead of the

desirable 85 % MCR.

It has to be highlighted that the values measured here are specific fuel consumptions

for the operation with MDO. When operating on IFO with a lower calorific value the

fuel consumption will increase accordingly (see Table 2) to an average of

260.5 g/kWh (with a variation from 236.0 g/kWh to 286.3 g/kWh).

3.1.3 Development of bunker oil prices

After a stabilisation of bunker oil prices between 1988 and 2000 there is a quite

steady upward trend in the bunker oil prices since 2000 (see Fig. 3). While the

increase of the prices of MDO and MGO already started in early 2003 the prices for

HFOs remained quite stable until end 2004. Since then the price for HFOs almost

doubled within 10 months from approx. US$ 150 per ton in December 2004 to

US$ 300 per ton in September 2005.

Bunker oil prices for IFO 380 today reached a level of over US$ 300.- per ton

throughout the world with peak prices at Japan exceeding US$ 370.- per ton. Analysts

today do expect that the oil price will stay high or increase even more due to the

strong demand for oil products from China.

The price levels of lower quality fuels (IFOs / HFOs) and higher quality fuels (MDO /

MGO) in direct comparison at Rotterdam are shown in Fig. 4 and Fig. 6. While

IFO 180 is only approx. 10 15 US$/ton more expensive than IFO 380, MDO at

approx. US$ 600.-/ton is almost 2-times as expensive as IFO 380 (or US$ 300 more

per ton). For this reason most ship-board diesel engines today run on HFOs / IFOs.

Only in some special areas with high environmental regulations the operation on

MDO might be of advantage (e.g. the Baltic Sea). Marine Gas Oil (MGO) is even

more expensive. For electrical power generation MGO is mainly used in mobile power

packs that can be placed on deck in case of a shortage of ship-own electrical power

generation plant.


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Monthly Bunker Prices (380 cst)

0 $/t

50 $/t

100 $/t

150 $/t

200 $/t

250 $/t

300 $/t

350 $/t

1973

1974

1975

1976

1977

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2000

2001

2002

2003

2004

2005

2006

Date

BunkerPrice

CristobalFos

Fujairah

Genoa

Houston

Japan

Los Angeles

Philadelphia

Rotterdam

Singapore

Monthly Bunker Prices (180 cst)

0 $/t

50 $/t

100 $/t

150 $/t

200 $/t

250 $/t

300 $/t

350 $/t

1973

1974

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2005

2006

Date

BunkerPrice

CristobalFos

Fujairah

Genoa

Houston

Japan

Los Angeles

Philadelphia

Rotterdam

Singapore

Monthly Bunker Prices (MDO)

0 $/t

100 $/t

200 $/t

300 $/t

400 $/t

500 $/t

600 $/t

700 $/t

1973

1974

1975

1976

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2006

Date

BunkerPrice

Cristobal

Fos

Fujairah

Houston

Japan

Los Angeles

Philadelphia

Rotterdam

Singapore

Monthly Bunker Prices (MGO)

0 $/t

100 $/t

200 $/t

300 $/t

400 $/t

500 $/t

600 $/t

700 $/t

1973

1974

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2000

2001

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2003

2004

2005

2006

Date

BunkerPrice Cristobal

Fujairah

Genoa

Rotterdam

Singapore

Fig. 3: Long term monthly bunker prices for different fuel oils4

Monthly Bunker Prices at Rotterdam

0 $/t

100 $/t

200 $/t

300 $/t

400 $/t

500 $/t

600 $/t

1973

1974

1975

1976

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2004

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Date

BunkerPrice

MGO

MDO

180CST

380CST

Fig. 4: Long term monthly bunker prices at Rotterdam54 Source: Clarkson Research Studies 20055 Source: Clarkson Research Studies 2005


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Weekly Bunker Prices (380 cst)

0 $/t

50 $/t

100 $/t

150 $/t

200 $/t

250 $/t

300 $/t

350 $/t

400 $/t

04.

01.2

002

05.

03.2

002

04.

05.2

002

03.

07.2

002

01.

09.2

002

31.

10.2

002

30.

12.2

002

28.

02.2

003

29.

04.2

003

28.

06.2

003

27.

08.2

003

26.

10.2

003

25.

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003

23.

02.2

004

23.

04.2

004

22.

06.2

004

21.

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004

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10.2

004

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004

17.

02.2

005

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005

17.

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005

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08.2

005

15.

10.2

005

14.

12.2

005

Date

BunkerPrice

Cristobal

FosFujairah

Genoa

Houston

Japan

Los Angeles

Philadelphia

Rotterdam

Singapore

Weekly Bunker Prices (180 cst)

0 $/t

50 $/t

100 $/t

150 $/t

200 $/t

250 $/t

300 $/t

350 $/t

400 $/t

04.

01.2

002

05.

03.2

002

04.

05.2

002

03.

07.2

002

01.

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002

31.

10.2

002

30.

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002

28.

02.2

003

29.

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003

28.

06.2

003

27.

08.2

003

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003

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005

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005

Date

BunkerPrice

Cristobal

FosFujairah

Genoa

Houston

Japan

Los Angeles

Philadelphia

Rotterdam

Singapore

Weekly Bunker Prices (MDO)

0 $/t

100 $/t

200 $/t

300 $/t

400 $/t

500 $/t

600 $/t

700 $/t

800 $/t

04.0

1.

2002

05.0

3.

2002

04.0

5.

2002

03.0

7.

2002

01.0

9.

2002

31.1

0.

2002

30.1

2.

2002

28.0

2.

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29.0

4.

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28.0

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27.0

8.

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26.1

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25.1

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23.0

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23.0

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22.0

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21.0

8.

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20.1

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19.1

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2004

17.0

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18.0

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17.0

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16.0

8.

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15.1

0.

2005

14.1

2.

2005

Date

BunkerPrice

CristobalFos

Fujairah

Houston

Japan

Los Angeles

Philadelphia

Rotterdam

Singapore

Weekly Bunker Prices (MGO)

0 $/t

100 $/t

200 $/t

300 $/t

400 $/t

500 $/t

600 $/t

700 $/t

800 $/t

04.0

1.

2002

05.0

3.

2002

04.0

5.

2002

03.0

7.

2002

01.0

9.

2002

31.1

0.

2002

30.1

2.

2002

28.0

2.

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29.0

4.

2003

28.0

6.

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27.0

8.

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26.1

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25.1

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2003

23.0

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23.0

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16.0

8.

2005

15.1

0.

2005

14.1

2.

2005

Date

BunkerPrice Cristobal

Fujairah

Genoa

Rotterdam

Singapore

Fig. 5: Short term weekly bunker prices for different fuel oils6

Weekly Bunker Prices at Rotterdam

0 $/t

100 $/t

200 $/t

300 $/t

400 $/t

500 $/t

600 $/t

700 $/t

04.

01.

2002

05.

03.

2002

04.

05.

2002

03.

07.

2002

01.

09.

2002

31.

10.

2002

30.

12.

2002

28.

02.

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29.

04.

2003

28.

06.

2003

27.

08.

2003

26.

10.

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25.

12.

2003

23.

02.

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23.

04.

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22.

06.

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21.

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10.

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17.

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17.

06.

2005

16.

08.

2005

15.

10.

2005

14.

12.

2005

Date

BunkerPrice

MGO

MDO

180CST

380CST

Fig. 6: Short term weekly bunker prices at Rotterdam76 Source: Clarkson Research Studies 20057 Source: Clarkson Research Studies 2005


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3.2 Lub oil consumption

The second largest consumable of diesel engines is the lubrication oil. Depending on

the engine type the lub oil systems are different:

- Medium-speed 4-stroke engines only use circulation lub oil which also

lubricates the cylinder liners. Here the lub oil consumption usually depends

on the load of the engine, thus it is measured in g/kWh.

- Slow-speed 2-stroke engines use cylinder oil for direct lubrication of the

cylinder liner and circulation lub oil for the crank case and cross head

lubrication. The cylinder lub oil consumption usually depends on the load of

the engine, thus it is measured in g/kWh, while the circulation lub oil

consumption mainly depends on the number of revolutions and is therefore

usually expressed as kg / cylinder / day.

3.2.1 Nominal lub oil consumption

Table 4 shows the specific lub oil consumption for some 4-stroke and 2-stroke diesel

engines. When assuming that the 2-stroke engines will be operated at 90 % MCR the

circulation lub oil consumption of 7 11 kg/cyl/day can be transferred to approx.0.06 0.09 g/kWh. This means that the circulation lub oil consumption is only

approx. one tenth of the cylinder lub oil consumption.

Type Manufacturer Engine series Speed Power

Guangzhou Diesel 230 series 750 - 900 rpm 891 - 1,408 kW

Guangzhou Diesel 300 series 500 - 600 rpm 550 - 607 kW

Guangzhou Diesel 320 series 400 - 525 rpm 971 - 2,426 kW

MAN B&W L27/38 800 rpm 2,040 - 3,060 kW

MAN B&W L28/32 775 rpm 1,320 - 3,920 kW

MAN B&W L58/64 400 - 428 rpm 7,800 - 12,510 kW

MAN B&W K90MC 71 - 94 rpm 8,840 - 54,840 kW 0.7 - 1.2 g/kWh 7 - 10 kg/cyl/day

MAN B&W K98MC-C 94 - 104 rpm 24,840 - 79,940 kW 0.7 - 1.2 g/kWh 7.5 - 11 kg/cyl/day

Specific lub oil consumption

(manufacturer's data)

1.0 g/kWh

1.8 g/kWh

1.2 g/kWh

0.5 - 0.8 g/kWh

0.8 g/kWh

4-Stroke

Medium

Speed

2-Stroke

Slow Speed

1.5 g/kWh

Table 4: Specific lub oil consumption for some diesel engines as per manufacturers data


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3.2.2 Effective lub oil consumption (example)

In order to verify the manufacturers data the lub oil consumption of a 2,000 TEU

container ship has been analysed8. Table 5 shows the result of the analysis. In case of

cylinder oil of the main engine and circulation oil of the diesel generators the lub oil

consumption was less than specified by the manufacturer. Only the consumption of the

circulation lub oil of the main engine was approx. 60 % higher than specified.

However, the main engine circulation lub oil system has the lowest overall

consumption so that this discrepancy is of minor importance.

All in all the manufacturers data seem to be quite reliable.

Engine Maker / Type Lub oil systemManufacturer's

dataMeasured data

Cylinder lub oil 1.4 g/kWh 1.347 g/kWh

Circulation lub oil 6.0 kg/cyl/day 9.706 kg/cyl/day

Diesel GeneratorsMAN B&W

L28/32Circulation lub oil 1.6 g/kWh 1.328 g/kWh

Main EngineWrtsil New Sulzer

RTA 76

Table 5: Comparison between manufacturers and measured data for the specific lub oilconsumption of a 2,000 TEU container ship over a period of approx. one year

3.2.3 Lub oil prices

Lubrication oil prices can vary significantly depending on the specification of the oil.

Typical prices at the end of 2004 were approx. US$ 700.- to US$ 900.- per 100 litres.

Assuming a density of approx. 900 kg/m the price is approx. US$ 780.- to

US$ 1,000.- per ton.

Since the strong increase of oil prices in 2005 it is assumed that lub oil prices now

increases by approx. 50 % to approx. US$ 1,200.- to US$ 1,500.- per ton.

3.3 Efficiency of alternator

The efficiency of the alternator is the ratio between the electrical power at the

generator and the mechanical power of the diesel engine.

MechanicalAlternatorElectrical PP =

8 Same vessel as for the specific fuel oil consumption of the diesel generators


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Usually the efficiency of the alternator is around 95 %.

If a PTO (power take off) from the propeller shaft is used there usually a gear box is

installed to increase the alternator speed. In this case the mechanical efficiency of the

gear box has to be taken into consideration, too.

MechanicalAlternatorGearboxElectrical PP =

The efficiency of the gear box can be assumed to be approx. 97 %, so that the overall

efficiency of gear box and alternator would be 92.15 %.

4 Cost calculation

Based on the above explained relations the specific cost calculation per electrical kWh

can be made up as shown in Table 6. The example calculation is based on the use of

MDO (as can be seen from the heating value) at a price of US$ 600.- per ton. The

specific fuel consumption is set to be 246.5 g/kWh. The overall specific cost then add

up to approx. 15 ct/kWh in this case. The lub oil consumption is only making up

approx. 1.3 % of the overall cost while the main cost factor is the fuel oil. When using

HFOs / IFOs this proportion will increase to approx. 2.5 %.

600 $/t

42,7 MJ/kg

11,9 kWh/kg

36%95%

34,2%

234,2 g/kWh

246,5 g/kWh

Overall specific fuel cost 4,109 ct/MJ14,791 ct/kWh

1300 $/t

1,50 g/kWh1,58 g/kWh

0,205 ct/kWh

14,996 ct/kWh

Specific fuel consumption (electrical power)

Spec. lub oil cost (electrical power)

Specific fuel Cost

Overall specific cost

Spec.lub oil consumption (mechanical power)

Lub oil cost

Overall efficiency

Efficiency of alternatorThermal efficiency of diesel engine

Lower heating value

Specific fuel consumption (mechanical power)

Spec.lub oil consumption (electrical power)

Table 6: Cost calculation (yellow fields are input fields)


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Table 7 shows the specific cost when varying the specific fuel consumption and the fuel

oil price.

Thermal

Efficiency

Specific Fuel

Consumption100 $/t 200 $/t 300 $/t 400 $/t 500 $/t 600 $/t 700 $/t 800 $/t 900 $/t

25% 355,0 gr/kWh 3,8 ct/kW h 7,3 ct/kW h 10,9 ct/kW h 14,4 ct/kW h 18,0 ct/kW h 21,5 ct/kW h 25,1 ct/kW h 28,6 ct/kW h 32,2 ct/kW h



28% 317,0 gr/kWh 3,4 ct/kWh 6,5 ct/kW h 9,7 ct/kWh 12,9 ct/kWh 16,1 ct/kW h 19,2 ct/kW h 22,4 ct/kWh 25,6 ct/kWh 28,7 ct/kW h


















46% 192,9 gr/kWh 2,1 ct/kWh 4,1 ct/kWh 6,0 ct/kWh 7,9 ct/kWh 9,9 ct/kWh 11,8 ct/kWh 13,7 ct/kWh 15,6 ct/kWh 17,6 ct/kWh










other relevant input data: Lower heating value 42,7 MJ/kg Specific lub oil consumption 1,50 gr/kWh

Efficiency of alternator 95% Lub oil price 1300 $/t

Specific fuel consumption is related to electrical kWh at alternator output

Efficiency

ofdieselengine

Specific Electrical Energy Cost on Ships

Fuel Oil Price

Table 7: Calculated specific cost (per kWh electrical energy) depending on the thermal efficiency ofthe diesel engine and the fuel oil price


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5 Summary

The results of the cost calculations are shown in Fig. 7. Taking into consideration thefour main potential ways of generating electrical power on board ships the following

areas as show in Fig. 7 can be separated:

Cost of Electrical Power

0,0 ct/kWh

5,0 ct/kWh

10,0 ct/kWh

15,0 ct/kWh

20,0 ct/kWh

25,0 ct/kWh

30,0 ct/kWh

35,0 ct/kWh

100 $/t 200 $/t 300 $/t 400 $/t 500 $/t 600 $/t 700 $/t 800 $/t 900 $/t

Bunker Price

SpecificCost

350,0 gr/kWh340,0 gr/kWh330,0 gr/kWh320,0 gr/kWh310,0 gr/kWh300,0 gr/kWh290,0 gr/kWh

280,0 gr/kWh270,0 gr/kWh260,0 gr/kWh250,0 gr/kWh240,0 gr/kWh230,0 gr/kWh220,0 gr/kWh210,0 gr/kWh200,0 gr/kWh190,0 gr/kWh180,0 gr/kWh170,0 gr/kWh160,0 gr/kWh150,0 gr/kWh

HFO / IFO operationof diesel generators

MDO operationof diesel generators

HFO / IFO operation

of main engine with

shaft generator

Specific fuel

consumption related

to electrical kWh

MGO operation

of power packs

Fig. 7: Calculated specific cost (per kWh electrical energy) depending on the specific fuelconsumption (per electrical kWh) of the diesel engine and the fuel oil priceMGO operation of mobile diesel generators (power packs) with a specific fuel

consumption varying from 280 to 330 g/kWh and fuel oil prices between US$ 600 to

US$ 700 per ton. The resulting specific cost will range from approx. 17.0 ct/kWh to

23.0 ct/kWh.

MDO operation of diesel generators with a specific fuel consumption varying

from 210 to 260 g/kWh and fuel oil prices between US$ 600 to US$ 700 per ton. The

resulting specific cost will range from approx. 12.5 ct/kWh to 18.5 ct/kWh.

HFO/IFO operation of diesel generators with a specific fuel consumption varying

from 240 to 290 g/kWh (due to lower calorific value) and fuel prices between

US$ 300 to US$ 400 per ton. The resulting specific cost will range from approx.

7.5 ct/kWh to 12.0 ct/kWh.


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HFO/IFO operation of main engine with shaft generator with a specific fuel

consumption varying from 190 to 220 g/kWh (due to lower calorific value and gear

box but better efficiency of the engine and operation at optimum load) and fuel pricesbetween US$ 300 to US$ 400 per ton. The resulting specific cost will range from

approx. 6.0 ct/kWh to 9.0 ct/kWh.

Hamburg, the 17th September 2005

(this document has been transmitted by emailand is therefore not signed)

Dr.-Ing. Yves WildOfficially appointed andSworn expert for RefrigerationChamber of Commerce, Hamburg

Calorific Value of HFO and MDO Comparison Report

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