Economics of Steam Traction
for the
Transportation of Coal by Rail
Chris Newman
Beijing, China
Economics of Modern Steam Traction in Transportation of Coal by Rail
Name: Chris Newman
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Professional Engineer specializing in
materials handling and transportation
21 years in Australian grain handling industry and
15 years in China, including10 years as technical
consultant on $1 billion World Bank grain storage and rail
transportation project;
A leading member of “5AT Project” that aims to build a hew high
speed locomotive as a “modern steam” demonstrator;
Since 2004 has undertaken several studies on the economics of
steam traction for coal haulage and has written and presented
papers on the subject.
Economics of Modern Steam Traction in Transportation of Coal by Rail
Synopsis
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Steam traction was never fully developed before its eclipse by
diesel power in the mid 20th century;
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The development of steam traction was continued through the
second half of the 20th century by the late L.D. Porta and
several of his disciples, with a doubling of the thermal
efficiency of “classic” steam traction.
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The economics of steam traction for coal haulage from mines
to port or to point of use, appear much better than diesel or
electric traction in developing countries.
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The economics of “modern steam” traction appear especially
promising over the longer term.
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Future development of steam traction could see efficiency
levels approaching those of diesel traction.
Economics of Modern Steam Traction in Transportation of Coal by Rail
Presentation Summary
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Preliminaries
Introduction to Steam Traction
“Modern Steam” Advancements
Loco Performance Comparisons
Railway Operation
Rolling Stock Requirements
Cost Comparisons
Environmental Considerations
Local Community Benefits
Conclusions
TOTAL
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4 pages
3 pages
9 pages
10 pages
15 pages
15 pages
23 pages
12 pages
1 page
5 pages
97 pages
Economics of Modern Steam Traction in Transportation of Coal by Rail
Part 1
Introduction to Steam Traction
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Technology dates from 1803 during the time of the Industrial
Revolution in Britain;
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Technology developed empirically over 150 years with
inadequate understanding of scientific principles;
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1950s-designed steam locomotives were slower, less efficient,
less reliable and more polluting than they need have been;
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Steam’s ability to operate without adequate maintenance meant
that it did operate with inadequate maintenance;
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Steam’s old fashioned image plus “good enough” engineering
standards made the diesel option appear modern and attractive
Economics of Modern Steam Traction in Transportation of Coal by Rail
Introduction to Steam Traction
Inside a Locomotive
• Fuel burned in firebox creates high pressure steam in boiler.
• Superheated steam drives pistons (on both sides of loco) backwards and forwards.
• Connecting rods transmit piston forces to cranks that cause the driving wheels to rotate
Economics of Modern Steam Traction in Transportation of Coal by Rail
Introduction to Steam Traction
Steam’s Image
• Whilst steam’s image declined
in post-war years, it
successfully powered the
world’s railways for 125 years:
• Steam locos hauled
prodigious loads in the USA.
• When replaced with diesels,
two or three locos had to be
substituted for one steamer.
Economics of Modern Steam Traction in Transportation of Coal by Rail
Part 2 - “Modern Steam” Advancements
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Thermodynamic theories first put to use by French engineer
André Chapelon in the 1930s.
Chapelon’s designs achieved Power / weight ratios of
>23 kW/tonne and outperformed contemporary electric traction.
All developments were done on locomotive rebuilds.
Economics of Modern Steam Traction in Transportation of Coal by Rail
“Modern Steam” Advancements
L.D. Porta – Argentinean Engineer (1922-2003)
• Took over steam development when
Chapelon retired;
• At age 24, rebuilt a locomotive that equalled
Chapelon’s best power/weight ratio;
• Director of Argentine’s National Technology
Institute from 1960 to 1982;
• Pioneered several important advancements
in steam traction.
Economics of Modern Steam Traction in Transportation of Coal by Rail
“Modern Steam” Advancements
Porta’s Advancements include:
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Improved coal combustion (reducing fuel
consumption and emissions);
Improved exhaust system;
Increased steam temperature;
Improved lubrication;
Improved water treatment;
Reduced steam leakage;
Improved insulation;
Improved adhesion;
Reduced maintenance costs.
Economics of Modern Steam Traction in Transportation of Coal by Rail
“Modern Steam” Advancements
Porta’s Achievements: Rio Turbio Railway
• 255km coal railway from
mine to port;
• Narrow gauge (750mm)
• Poor track quality –
light rail, no ballast;
• Max grade 0.3%;
• Tight curvature;
• Low grade coal for
locomotives.
• 18 tonne wagons with high
rolling resistance.
Economics of Modern Steam Traction in Transportation of Coal by Rail
“Modern Steam” Advancements
Porta’s Achievements: Rio Turbio Railway
• 48 tonne locos built by
Mitsubishi in 1956 and 1963
• Power Output increased from
520 kW to 900 kW by Porta
modifications;
• Ash clinkering problems overcome;
• 1700 tonne trains routinely hauled
(tested to 3000 tonnes);
• Very high mileages between
overhauls.
Economics of Modern Steam Traction in Transportation of Coal by Rail
“Modern Steam” Advancements
Porta’s Legacy
Porta’s theories have been adopted in:
•…. South Africa by David Wardale;
•…. Argentina by Shaun McMahon;
•…. Australia and Russia by Phil Girdlestone;
•…. Argentina, Paraguay and Cuba by Porta himself.
Wardale’s “Red Devil” --- rebuild of
SAR 1950s Krupp-designed Class 25.
Achieved 60% increase in power, 40%
reduction in specific coal consumption.
Economics of Modern Steam Traction in Transportation of Coal by Rail
Porta’s Legacy (continued)
The 5AT – “Second Generation Steam”
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Conceived by David Wardale;
First new steam loco design to adopt Porta’s developments;
Designed for high speed operation - 200kph max, 180 kph continuous;
Target – tour and cruise trains in UK and Europe;
Fundamental Design Calculations completed;
Currently in final planning stage;
2008 launch planned to seek investment funding;
Design is readily adapted for freight haulage (using smaller wheels).
Economics of Modern Steam Traction in Transportation of Coal by Rail
“Modern Steam” Advancements
The 8AT
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Uses same boiler, cylinders, cab, tender and motion as 5AT;
1.325 m dia. driving wheels give 192 kN drawbar tractive force;
Max power - 2100 kW at drawbar at 120 km/h; 1800 kW at 80 km/h;
Starting tractive force – 192 kN at the drawbar;
21 tonne axle load (including ballast) to control slipping;
Able to haul 3200 tonne coal trains at >80 km/h on level track.
Economics of Modern Steam Traction in Transportation of Coal by Rail
Steam Traction Haulage Capacity
American 2-8-0 locomotive (c.1912) of similar size and “tractive effort” to the 8AT, but
with no superheat, low boiler pressure and journal bearing, hauling 6,500 tonnes (net?)
Coal Transportation in Indonesia
The Steam Option
_______________________________________________
Part 3 – Haulage Capabilities
Alternative Traction Types
used in Cost Comparisons
Chinese SS-3 4320 kW Electric Loco
Chinese DF4-D 2940 kW Diesel Loco
Chinese QJ 2600 kW Steam Loco
8AT 2100 kW Modern Steam Loco
Economics of Modern Steam Traction in Transportation of Coal by Rail
Principal Data for Alternative Traction Types
Loco Type
QJ
Steam
8AT
Steam
Diesel
DF4-D
Electric
SS-3
Wheel Arrangement
2-10-2
2-8-0
Co-Co
Co-Co
2600
2100
2940
4320
Max Speed (km/h)
80
100
100
100
Loco Weight excluding tender (tonnes)
134
96
138
138
Axle Loading (tonnes)
20.5
21
23
23
Adhesive Weight (tonnes)
100.5
84
138
138
Starting Wheel Rim Tractive Effort (kN)
287
206
480
490
Continuous Wheel Rim TE at 20km/h
244
130
385
385
Required Starting Friction Coefficient
0.29
0.25
0.36
0.36
Max Power Output kW (wheel rim)
Economics of Modern Steam Traction in Transportation of Coal by Rail
Performance Data for Alternative Traction Types (3)
SS-3 and DF4-D Performance Graphs
Tractive Force vs. Speed
Economics of Modern Steam Traction in Transportation of Coal by Rail
Performance Data for
Alternative Traction
Types (1)
QJ Performance Graphs
Tractive Force vs. Speed
over a range of cut-offs and
steaming rates
Economics of Modern Steam Traction in Transportation of Coal by Rail
Performance Data for Alternative Traction Types (2)
8AT Performance Graphs
Maximum Tractive Force and Power vs. Speed
Economics of Modern Steam Traction in Transportation of Coal by Rail
Summary of Speed vs. Drawbar TE Characteristics for Traction Options
Drawbar Tractive Effort values in kN, Power values in kW
QJ1
8AT2
SS-33
DF4-D
Speed
TE
Power
TE
Power
TE
Power
TE
Power
0
271
0
192
0
474
0
481
0
10
267
741
180
500
474
1318
417
1158
20
244
1353
163
906
401
2228
387
2149
30
216
1804
139
1161
277
2308
371
3094
40
176
1954
117
1301
209
2319
360
4002
50
146
2021
100
1389
165
2297
291
4047
60
121
2021
91
1515
136
2266
243
4051
70
102
1980
84
1626
114
2223
207
4017
80
85
1886
77
1711
99
2192
178
3964
Note 1: For QJ locomotives, the TE and Power values are estimated from the Speed-TE curves supplied by China
National Railways at steaming rate of 75 kg/hr/m2.
Note 2: In order to base the 8AT’s performance on the same assumption as the Chinese locos, its calculated
maximum drawbar tractive effort values have been reduced in the same proportion as those of the QJ resulting from
the adoption of a 75 kg/h/m2 steaming rate instead of its maximum of 95 kg/hr/m 2. Thus the 8AT’s estimated TE and
power values have been reduced progressively from zero at low speeds up to 20% at 80 km/h.
Note 3: SS-3 figures in italics have been reduced (by estimate) to keep its wheel-rim power below its rated power.
Economics of Modern Steam Traction in Transportation of Coal by Rail
Comparison of Formulae for Determining
Specific Rolling Resistance of Freight Stock
Economics of Modern Steam Traction in Transportation of Coal by Rail
Chinese Formulae for Specific Rolling Resistance of Wagons
Loaded Wagons: RR = 0.92 + 0.0048V + 0.000125V2 N/tonne;)
) where V is speed in km/h.
Empty Wagons : RR = 2.23 + 0.0053V + 0.000675V2 N/tonne;)
Gradients: RG = 10 x G N/tonne where G is the gradient in %;
Curvature: RC = (600/r) x LC/LT when LC < LT or RC = (600/r) when LC>LT,
where r = the curve radius in metres, LC = the curve length and LT = the train length.
Based on these formulae and the speed/traction force values already derived, it is easy to
calculate the steepest gradient that a locomotive will be able to climb at constant speed
with any given load using the formula:
(TE DB  RR  WT )
G
10  (WT  WL )
Where TEDB is the drawbar tractive effort of the locomotive.
Economics of Modern Steam Traction in Transportation of Coal by Rail
Max Gradient at Constant Speed over range of Train Loads
for QJ class locomotive operating at 75 kg/m2/hr steaming rate.
Speed
Km/h
Gross Train Weight
dbTE
on
level
track
Specific
Train
Resist'ce
kN
N/tonne
5
275
9.3
2.26
1.57
1.19
0.95
0.79
0.67
0.58
0.56
10
267
9.6
2.19
1.51
1.15
0.92
0.76
0.64
0.55
15
255
10.0
2.08
1.44
1.09
0.87
0.72
0.61
20
244
10.5
1.98
1.37
1.03
0.82
0.68
25
228
11.0
1.84
1.27
0.95
0.76
30
212
11.5
1.70
1.17
0.88
35
194
12.2
1.54
1.05
40
177
12.9
1.39
45
160
13.6
50
146
55
tonne
tonne
tonne
tonne
Tonne
tonne
tonne
tonne
tonne
tonne
tonne
1000
1500
2000
2500
3000
3500
4000
4100
5000
6000
7000
0.45
0.36
0.30
0.55
0.43
0.34
0.28
0.52
0.51
0.40
0.32
0.26
0.57
0.49
0.48
0.38
0.30
0.24
0.62
0.52
0.45
0.43
0.34
0.27
0.21
0.69
0.57
0.47
0.40
0.39
0.30
0.23
0.19
0.78
0.62
0.50
0.42
0.35
0.34
0.26
0.20
0.15
0.94
0.70
0.54
0.44
0.36
0.30
0.29
0.22
0.16
0.12
1.25
0.84
0.62
0.48
0.38
0.31
0.26
0.25
0.18
0.13
0.09
14.4
1.11
0.74
0.54
0.41
0.33
0.26
0.21
0.20
0.14
0.10
0.06
134
15.3
1.00
0.66
0.48
0.36
0.28
0.22
0.18
0.17
0.11
0.07
0.04
60
122
16.3
0.90
0.59
0.42
0.31
0.23
0.18
0.14
0.13
0.08
0.04
0.01
65
113
17.3
0.81
0.52
0.36
0.26
0.19
0.14
0.11
0.10
0.05
0.01
-0.01
70
103
18.3
0.72
0.45
0.31
0.22
0.15
0.11
0.07
0.07
0.02
-0.01
-0.04
75
93
19.5
0.63
0.38
0.25
0.17
0.11
0.07
0.04
0.03
-0.01
-0.04
-0.06
80
85
20.6
0.55
0.33
0.20
0.13
0.07
0.04
0.01
0.00
-0.04
-0.06
-0.08
Climbable Gradient at Given Load and Speed - %
Economics of Modern Steam Traction in Transportation of Coal by Rail
Train Haulage Estimates for Steam, Diesel an Electric Traction
Old Steam
Mod St
Diesel
Electric
Loco Type
QJ
8AT
DF4-D
SS-3
Loco Weight (including tender)
200
170
138
138
2200*
1700*
2940
4320
Max Design Speed (km/h)
85
100
100
100
Max Continuous Speed with 3,000 t train
85
85
100
100
Max Continuous Speed with 3,500 t train
85
80
100
100
Max Continuous Speed with 4,000 t train
80
70
95
100
Max Continuous Speed with 5,000 t train
70
60
75
100
Max Continuous Speed with 6,000 t train
65
(55)
70
100
Max Continuous Speed with 7,000 t train
60
-
65
100
Max Continuous Speed with 8,000 t train
(55)
-
60
90
Max Continuous Speed with 9,000 t train
-
-
55
78
Max train weight for 80km/h on level track1
4,100
3,200+
4,700
8,700
Stalling (5 km/h) Grade for Max Train Size
0.56%
0.48%
0.91%
0.41%
Sustainable Speed on 0.5% grade (km/h)
17
-
27
-
Train (inc loco weight) / Loco Weight Ratio
21.5
19.8
36.5
66.2
Train Weight / Loco Power Ratio (inc loco)
1.96
1.98
2.07
2.12
Max train wt for 20km/h on 1.0% grade (t)
2000
1300
3600
3400
Estimated Max start-able gross train wt (t)
7800
5500
>10000
>10000
Power Rating kW (wheel rim)
* Note: The QJ delivers 2600 kW at full boiler output; the 8AT should produce 2100 kW at the drawbar at full power
Economics of Modern Steam Traction in Transportation of Coal by Rail
Speed-Power Comparison between Traction Types
Speed vs. Power Curves
4500
4000
3500
SS-3
Power (kW)
3000
DF4-D
8AT
2500
QJ
2000
1500
1000
500
0
0
10
20
30
40
50
Speed (km/h)
60
70
80
90
Economics of Modern Steam Traction in Transportation of Coal by Rail
Acceleration/Speed/Time Comparison between Traction Types
Time vs. Speed Curves at Design Loads
Speed vs. Acceleration Curves at Design Load
0.10
90
SS-3 (6230t)
DF4-D (4650t)
0.09
80
8AT (3162t)
QJ (3720t)
70
0.07
SS3 (6230t)
Speed (km/h)
60
0.06
0.05
0.04
DF4-D(4650t)
QJ (3720t)
40
0.03
30
0.02
20
0.01
10
0.00
0
20
40
60
8AT (3162t)
50
0
80
0
Speed (km/h)
200
400
600
800
1000
Time (secs)
Time vs. Distance
50
40
Distance (km)
Acceleration (m/s/s)
0.08
30
SS-3 (6230t)
DF4-D (4650t)
8AT (3162t)
QJ (3720t)
20
10
0
0.0
10.0
20.0
30.0
-10
Time (mins)
40.0
50.0
60.0
Economics of Modern Steam Traction in Transportation of Coal by Rail
Part 4
Railway Operation
Basic Premises
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Single purpose, single route railway only for transporting coal from
a mine site to an export terminal;
No connecting routes; no non-coal traffic;
Simple 24 hour per day “merry-go-round” train rotation;
Single line operation with passing loops;
Trains loaded and unloaded as soon as they arrive at the loading
and unloading stations;
Locomotives remain attached to their trains including during
routine servicing.
Economics of Modern Steam Traction in Transportation of Coal by Rail
Railway Operation
Basic Premises for Idealized
Synchronized System
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Passing loops are equidistant from one another;
Trains all travel at the same speed (50km/h average);
Full trains will arrive at passing loop at the same time as an empty
train coming the other way;
Trains depart from the loading and unloading stations immediately
after the arrival of the arrival train coming from opposite direction;
Time interval between trains remains constant = twice the time
taken to travel between passing loops.
Economics of Modern Steam Traction in Transportation of Coal by Rail
Railway Operation
Typical Train Movement Diagram
Average Travel Speed 50 km/h
Economics of Modern Steam Traction in Transportation of Coal by Rail
Railway Operation
Loading System Schematic Diagram
Economics of Modern Steam Traction in Transportation of Coal by Rail
Railway Operation
Unloading System Schematic Diagram
Economics of Modern Steam Traction in Transportation of Coal by Rail
Railway Operation
Passing Loop Schematic Diagram
Economics of Modern Steam Traction in Transportation of Coal by Rail
Railway Operation
Basic Premises for Idealized
Synchronized System
Time interval between trains remains constant = twice the time it
takes to travel between passing loops, or ti = 2 x dL÷ V
(where ti = time interval, dL distance between loops and V is the average train speed)
Minimum load in each train = target hourly throughput (t/h) x time
interval between trains, or Wt = Th x ti (where Wt is train weight and Th is
the target hourly throughput).
Thus the minimum train capacity Wt = Th x 2 x dL ÷ V. In other
words, it is determined by the train speed and the distance between passing
loops.
Economics of Modern Steam Traction in Transportation of Coal by Rail
Railway Operation
Basic Premises for Idealized
Synchronized System
Basic principle is:
• more passing loops allow the operation of smaller trains;
thus
• Smaller locomotives (hauling smaller trains) require more passing
loops to deliver the same quantity of coal.
thus
• large trains hauled by electric traction will require fewer passing
loops than shorter trains hauled by 8ATs.
Economics of Modern Steam Traction in Transportation of Coal by Rail
Railway Operation
Estimating Ideal Train Capacities
We have minimum train capacity Wt = Th x 2 x dL ÷ V.
If target annual throughput = 20 million tonnes per year, this equates to
62,500 tonnes per day over a 320 day year.
Assume the railway operation is only 75% efficient, then target daily
throughput = 83,333 tonnes per day or Th = 3472 t/h x 24 hours.
Thus if the railway length is 100 km, V = 50 km/h and there are 4 passing
loops, the distance between loops, dL = 20 km from which can be calculated
the minimum train capacity Wt = 3472 x 2 x 20 / 50 = 2778 tonnes.
If we assume the use of Chinese C70 wagons with a gross weight of 93
tonnes and tare weight of 23 tonnes, we can deduct that the train needs 40
wagons with a gross weight of 3720 tonnes and net weight of 2800 tonnes.
We can thus use the maximum train loads for each locomotive type to
determine the number of passing loops required for each type (see next slide).
Economics of Modern Steam Traction in Transportation of Coal by Rail
Railway Operation
Estimating Optimum Train Sizes to deliver 83,333 tonnes per day
in Chinese C70 wagons (93 tonnes gross, 23 tonnes tare)
Item
units
QJ
8AT
DF4
SS3
Max Haulage Capacity from Slide 26
Tonne
4,100
3,200*
4,700
8,700
Equiv net capacity with 70t net 23t tare wagons
tonne
3,086
2,409
3,538
6,548
Minimum required trains per day
No.
27
34.6
23.6
12.7
Max distance between trains at 50km/h
Km
44.4
34.7
50.9
94.3
Max distance between passing loops
Km
22.2
17.3
25.5
47.1
Theoretical number of passing loops in 100 km
No.
3.50
4.77
2.93
1.12
Actual minimum number of passing loops
No.
4
5
3
2
Minimum number of trains in transit
No.
5
6
4
3
Distance between passing loops
Km
20.0
16.7
25.0
33.3
48
40
60
80
2,778
2,315
3,472
4,630
40
34
50
67
Train Arrival Frequency
Required net tonnes per train
Minimum number of 70 t wagons
mins
Tonne
No.
Actual train load (net)
tonne
2,800
2,380
3,500
4,690
Actual train weight (gross)
Tonne
3,720
3,162
4,650
6,231
%
91%
99%*
99%
72%
Percentage of loco capacity required
Note: Calculated 8AT haulage capacity is 3700 t. Hence a 3162 t load may be no more than 85% of its capacity.
Economics of Modern Steam Traction in Transportation of Coal by Rail
Railway Operation
Train Movement Diagram
SS-3 Electric Traction with two passing loops
Economics of Modern Steam Traction in Transportation of Coal by Rail
Railway Operation
Train Movement Diagram
DF4-D Diesel Traction with three passing loops
Economics of Modern Steam Traction in Transportation of Coal by Rail
Railway Operation
Train Movement Diagram
QJ Steam Traction with four passing loops
Economics of Modern Steam Traction in Transportation of Coal by Rail
Railway Operation
Train Movement Diagram
8AT Steam Traction with five passing loops
Economics of Modern Steam Traction in Transportation of Coal by Rail
Railway Operation
Train Control (Signalling)
•
Make use of the constant train frequency to create a regular
system of train operation that requires rescheduling only in
emergencies;
•
Use standard safety systems such as track circuiting interlocked
with passing loop crossings fitted with run-away sidings (or catchpoints) to prevent trains meeting in opposite directions.
•
Fit each locomotive with GPS system to allow a Central Train
Control (CTC) to monitor each train position and send radio
instructions to each train operator to adjust speed for coordinating
passing operations and for maintaining schedules.
•
GPS positioning system to be linked to the track-circuit
interlocking system.
•
On-board “cab signalling” with no line-side signals.
Economics of Modern Steam Traction in Transportation of Coal by Rail
PART 5
Estimating Rolling Stock Requirements
Process:
•
The train movement diagrams (above) demonstrate that the
minimum number of trains (and locomotives) in transit = the
number of passing loops plus 1.
•
Further trains and locos need to be added to take account of:
o loading and unloading operations;
o Locomotive servicing;
o Locomotive and wagon maintenance;
o Breakdowns and emergencies.
Economics of Modern Steam Traction in Transportation of Coal by Rail
Estimating Rolling Stock Requirements
Estimating Target Loading and Unloading Rates
Requires a time-study taking into account:
• Transit time from main line to loading/unloading point;
• Time for administrative and safety checks;
• Time for refuelling, watering and servicing locomotives;
• Other non-productive time requirements.
Deducting the sum total of these times from the train
arrival/departure frequency allows target loading/unloading
rates to be calculated:
Economics of Modern Steam Traction in Transportation of Coal by Rail
Estimating Rolling Stock Requirements
Estimating Target Train Loading Rates
Activity
units
QJ
8AT
DF4
SS3
Net Train Capacity
tonne
2,800
2,380
3,500
4,690
Train Arrival Frequency
mins
48
40
60
80
Arrival checks and documentation
mins
3
3
3
3
Travel round 1.6 km balloon loop @ 20km/h
mins
5
5
5
5
Position train under loading chute
mins
1
1
1
1
Time to move train clear of loading chute
mins
1
1
1
1
Refill tender water tank
mins
8
6
-
-
Dispatch checks and documentation
mins
inc
inc
3
3
Time available for train filling
mins
30
24
47
67
Required Coal Loading Rate
t/h
5,600
6,000
4,450
4,200
Economics of Modern Steam Traction in Transportation of Coal by Rail
Estimating Rolling Stock Requirements
Loco Coaling and Watering Facility
• Locos will require coaling and watering at least once each 200km
round trip.
• Loco coal should be the best quality available from mine to
guarantee best performance.
• Main coaling facility should be located at (but separate from)
Coal Loading Station.
Economics of Modern Steam Traction in Transportation of Coal by Rail
Estimating Rolling Stock Requirements
“Scaled” schematic diagram of Train Loading Station
Economics of Modern Steam Traction in Transportation of Coal by Rail
Estimating Rolling Stock Requirements
Unloading Station
More complex than loading system because of the need to take
account of the unloading method (rotary or bottom dump) and also
locomotive servicing requirements.
• Steam traction will require ash removal, lubrication, sand refilling
etc. at least once per 200 km round trip, and may need refuelling,
rewatering and ash removal at each end of the line.
• Diesels will need refuelling and servicing every 2 or 3 round trips.
Time available for unloading wagons may thus be very short, requiring
high unloading rates that may be unachievable with a rotary unloader
(limited to ~7,000 t/h max).
Thus it may be necessary to have two (or more) trains at the unloading
station at any time – see next slide.
Economics of Modern Steam Traction in Transportation of Coal by Rail
Estimating Rolling Stock Requirements
Unloading Sequence
Max loco servicing time available – 38 mins
Economics of Modern Steam Traction in Transportation of Coal by Rail
Estimating Rolling Stock Requirements
Loco Servicing
For unload sequence shown in previous slide, loco is serviced while still
connected to its train. This will require specially designed servicing facility
incorporating the following components:
Economics of Modern Steam Traction in Transportation of Coal by Rail
Estimating Rolling Stock Requirements
• If servicing time > 38 minutes, then it is better for
locos to be serviced in workshop;
• This requires detaching locos from trains, and
recoupling them after servicing;
• Reconnected trains need to be brake-tested before
departure, which can take 30 to 60 minutes.
• Following sequence illustrates how this might be
done.
Economics of Modern Steam Traction in Transportation of Coal by Rail
Estimating Rolling Stock Requirements
Unloading Sequence with locos serviced in workshop
Economics of Modern Steam Traction in Transportation of Coal by Rail
Estimating Rolling Stock Requirements
From similar sequence diagrams drawn for each traction type, the
following deductions can be made:
Minimum Number of Locos and Trains Required to Operate Railway
Item
Units
QJ
8AT
DF4
SS3
Required number of passing loops in 100 km
unit
4
5
3
2
Minimum number of trains in transit
unit
5
6
4
3
Required train capacity (net)
tonne
2,800
2,380
3,500
4,690
Required train capacity (gross)
tonne
3,720
3,162
4,650
6,231
Minimum number of locos/trains at loading station
unit
1
1
1
1
Minimum train loading rate
t/h
5,600
6,000
4,450
4,200
Loco detached for servicing at unload station
unit
no
no
no
No
Required rotary unloader capacity
t/h
1x5000
1x5000
1x5000
1x7000
Number of trains at unloading station
unit
2
2
2
1
Number of locos at unloading station
unit
2
2
2
1
Available time for loco servicing
mins
43
35
50
25
Economics of Modern Steam Traction in Transportation of Coal by Rail
Estimating Rolling Stock Requirements
Additional locomotive requirements to cover maintenance can be
estimated from maintenance frequency, maintenance downtime, and
annual mileage of locomotives.
Annual mileage is calculated as follows:
Units
QJ
8AT
DF4
SS3
Number of wagons per train
Unit
40
1
1
1
Loco standing time at loading station
Mins
48
40
60
80
Number of locos at unloading station
unit
2
2
1
1
Loco standing time at unloading station
Mins
96
80
60
80
Travel time on line (both ways)
Mins
120
120
120
120
Total turnaround time for each loco
hours
6.4
6.0
6.5
7.1
Number of round trips per day per loco
unit
3.8
4.0
3.7
3.4
Distance travelled by each loco per day
km
750
800
738
675
Annual mileage for each locomotive
km
240,000
256,000
236,000
216,000
Economics of Modern Steam Traction in Transportation of Coal by Rail
Estimating Rolling Stock Requirements
Servicing requirements are as follows (from Chinese manufacturers):
Annual mileage for each locomotive
km
240,000
256,000
236,000
216,000
Major overhaul period
km
250,000
500,000
700,000
1,200,000
15
15
15
15
83,333
125,000
233,333
400,000
6
6
6
6
22,500
24,000
30,000
40,000
2
2
2
2
Time to complete major overhaul
Intermediate overhaul period
Time to complete major overhaul
Scheduled maintenance period
Time to complete scheduled maintenance
days*
km
days*
km
days*
Number of major overhauls per year
unit
0.96
0.51
0.34
0.18
Time under major overhauls per year
days*
14.4
7.9
4.4
2.7
unit
1.92
1.54
0.68
0.36
Time under intermediate overhauls
days*
11.5
9.2
3.5
2.2
Scheduled maintenances per year
unit
10.67
10.67
6.86
4.86
Time under scheduled maintenance
days*
21.3
21.3
11.9
9.7
Total time under maintenance per year
days*
47.3
38.2
19.8
14.6
Percentage of time under maintenance
%
15%
12%
6%
5%
Percentage of loco fleet under maintenance
%
15%
12%
6%
5%
Number of locos to cover maintenance
theory
1.18
1.08
0.43
0.23
Number of locos to cover maintenance
actual
2
2
1
1
Intermediate overhauls per year
* The estimated times for overhauls and scheduled maintenance are based on 24 hour per day operation, and have been increased above
Chinese time estimates. These times will increase if working days are shorter.
Economics of Modern Steam Traction in Transportation of Coal by Rail
Estimating Rolling Stock Requirements
Summary of Loco Requirements
Minimum number of trains in transit
unit
5
6
4
3
Minimum number of locos/trains at
loading station
unit
1
1
1
1
Number of locos at unloading station
unit
2
2
2
1
Number of locos to cover maintenance
actual
2
2
1
1
Stand-by locos to cover breakdown etc§
est’d
3
3
2
1
Total Loco Fleet Required
unit
13
14
10
7
§ The number of standby locomotives is based on subjective judgement, taking into
account the difference between the actual number of locos provided to cover
maintenance and the theoretical number that are required.
Economics of Modern Steam Traction in Transportation of Coal by Rail
Estimating Rolling Stock Requirements
Summary of Wagon Requirements
Number of trains in transit
unit
5
6
4
3
Number of trains at loading station
unit
1
1
1
1
Number of trains at unloading station
unit
2
2
2
1
Number of trains to cover maintenance
est’d
1
1
1
1
Total number of trains required
unit
9
10
8
6
Number of wagons per train
unit
40
34
50
67
Total Wagon Fleet Required
unit
360
340
400
402
Note:- Longer trains require more wagons. This is because individual wagons spend
more time idle waiting for their (longer) trains to unload.
At $75,000 per wagon, the cost difference between the cost of the wagon fleets for
diesel and 8AT steam traction is around $4.5 million - a “hidden” saving for steam.
Other hidden savings from smaller (steam hauled) trains include lower drawgear loads
and lower rail and flange wear on curves.
Economics of Modern Steam Traction in Transportation of Coal by Rail
PART 6
Locomotive Cost Comparisons
1. Estimate capital cost (including locomotive infrastructure
requirements), and amortization period;
2. Estimate annual maintenance costs;
3. Estimate labour costs associated with loco operation & servicing;
4. Estimate water costs for steam locos, including treatment;
5. Estimate fuel consumption and compare with recorded data;
6. Estimate fuel costs.
Economics of Modern Steam Traction in Transportation of Coal by Rail
Locomotive Cost Comparisons
Estimating Capital Costs
•
•
•
•
•
•
•
Steam loco fuelling and servicing facilities – estimated price $4 million;
Diesel loco fuelling and servicing facilities – estimated price $2 million;
Electric loco servicing facilities – estimated price $1 million;
Electrical infrastructure - $530,000 per km (from Chinese data)
QJ cost including reconditioning and shipping ~ $0.4 million (quoted)
DF4-D and SS-3 cost including shipping ~ $1.25 million (quoted)
8AT steam loco (built in China or similar) ~ $2.5 million (estimated)
Note: Estimate unit cost of 8AT locomotives includes a margin to cover
the cost of design, building and testing of a prototype loco.
Economics of Modern Steam Traction in Transportation of Coal by Rail
Locomotive Cost Comparisons
Estimating Capital Costs
Capital Cost and Depreciation Estimates
units
QJ
8AT
DF4
SS3
Electrical infrastructure cost
$m
61.3
Servicing infrastructure cost
$m
4.0
4.0
2.0
1.0
Number of locomotives required
unit
13
14
10
7
Cost per locomotive
$m
0.40
2.5
1.25
1.25
Cost of locomotive fleet
$m
5.20
35.0
12.0
8.40
Depreciation period for infrastructure
years
25
25
25
25
Depreciation period for locos
Years
10
25
25
25
Amortized cost of infrastructure
$m/year
0.160
0.160
0.080
2.493
Amortized cost of locomotives
$m/year
0.520
1.400
0.480
0.360
Total Amortization Cost of Traction
$m/year
0.680
1.560
0.560
2.829
Economics of Modern Steam Traction in Transportation of Coal by Rail
Locomotive Cost Comparisons
Estimating Loco Maintenance Costs
Maintenance Schedules for Chinese Locomotives
Item
Major Overhaul Period
Major Overhaul Cost
Intermediate Overhaul Period
Intermediate Overhaul Cost
Regular Maintenance Period
Regular Maintenance Cost
QJ Steam
DF4 Diesel
SS3 Electric
250,000 km or 3 yrs
700,000 km or 6 yrs
1,200,000 km or 10
yrs
$45,000 (2006)
$200,000 (1997)
$250,000 (1997)
83,000 km or 1 yr
250,000 km or 2 yrs
400,000 km or 3 yrs
$25,000 (2006)
$50,000 (1997)
$65,000 (1997)
22,500 km (assumed)
30,000 km or 3 mths
40,000 km or 6 mths
$5000 (assumed)
$10,000 (1997)
$12,000 (1997)
Economics of Modern Steam Traction in Transportation of Coal by Rail
Locomotive Cost Comparisons
Estimating Loco Maintenance Costs
Proposed Maintenance Schedules for 8AT Locos
Major Overhaul Period
Major Overhaul Cost
Intermediate Overhaul Period
Intermediate Overhaul Cost
Regular Maintenance Period
Regular Maintenance Cost
500,000 km or 3 yrs
$50,000
125,000 km or 1 yr
$25,000
24,000 km
$5,000
8AT maintenance frequencies are based on the mileages achieved by the
Porta-modified RFIRT locomotives operating in Argentina (see next slide).
Costs are based on quoted maintenance costs for Chinese steam locos.
Economics of Modern Steam Traction in Transportation of Coal by Rail
Reliability Record from Rio Turbio Railway’s Locos
that incorporated some (minor) Porta improvements
• 480,000 km before main (white metal)
bearings needed replacing = 180 million
revolutions of the 850mm dia driving wheels;
• 70,000 km between tyre profiling = 26 million
revolutions;
• No superheater replacements in 500,000 km
despite high steam temperatures (>400oC);
• No boiler tube replacement in 400,000 km
(apart from tubes damaged during installation);
• No boiler repairs in 400,000 km of service;
• Piston rod packings lasted 400,000 km (150 million
revolutions);
• Max steam leakage 1.7% of max evaporation after
70,000 km.
Economics of Modern Steam Traction in Transportation of Coal by Rail
Locomotive Cost Comparisons
Estimating Loco Maintenance Costs
units
QJ
8AT
DF4
km
250,000
500,000
700,000
1.2m
$
45,000
50,000
230,000
287,500
km
83,000
125,000
233,000
400,000
$
25,000
25,000
57,500
74,750
km
22,500
24,000
30,000
40,000
Regular maintenance cost
$
5,000
5,000
11,500
13,800
Average loco km per year
km
111,000
123,000
115,200
123,400
Major maintenance cost / loco / year
$
19,900
12,300
37,800
29,600
Interm’t maintenance cost / loco / year
$
16,600
16,500
14,200
11,500
Regular maintenance cost / loco/ year
$
24,600
25,700
44,100
42,600
Total maintenance cost / loco / year
$
61,100
54,500
96,200
83,700
Major overhaul frequency
Major overhaul cost
Intermediate overhaul frequency
Intermediate overhaul cost
Regular maintenance frequency
SS3
Number of locos in fleet
unit
13
14
10
7
Total cost of maintenance per year
$m
0.795
0.763
0.962
0.586
Economics of Modern Steam Traction in Transportation of Coal by Rail
Locomotive Cost Comparisons
Estimating Labour Costs
(associated with locomotive operation and servicing)
•
•
•
•
•
•
•
•
Each operating steam loco will require 2 operators or “enginemen”;
Each operating diesel and electric loco will require 1 operator;
“Old steam” traction will require 8 people for locomotive servicing duties;
“Modern steam” traction will require 4 people for locomotive servicing
duties;
Diesel traction will require only 2 servicemen at the servicing depot;
Electric traction will require 6 servicemen, including 2 at the servicing
depot and one linesman in each section of track between passing loops;
No allowance is made for maintenance personnel whose costs are
included maintenance cost estimates.
Operating and servicing personnel will cost $5,000 per annum.
Economics of Modern Steam Traction in Transportation of Coal by Rail
Locomotive Cost Comparisons
Estimating Labour Costs
(associated with locomotive operation and servicing)
units
QJ
JS
SY
8AT
DF4
SS3
Labour shifts per day
3
3
3
3
3
3
Crew members per loco
2
2
2
2
1
1
Number of locos in operation
8
9
16
9
7
5
48
54
96
54
21
15
8
8
8
4
2
6
Total servicing crew
24
24
24
12
6
18
Total labour requirement
72
78
120
66
27
33
$
5,000
5,000
5,000
5,000
5,000
5,000
$m
0.360
0.390
0.600
0.330
0.135
0.165
Total loco crew
Servicing crew per shift
Unit labour cost per annum
Labour cost per annum
Note: $5000 p.a. wage rate is generous for developing countries
Economics of Modern Steam Traction in Transportation of Coal by Rail
Locomotive Cost Comparisons
Estimating Water Costs
(steam locos only)
• Assumed water cost - $0.30 per tonne;
• Assumed water treatment cost - $1.00 per tonne (based on UK
costs)
• QJ performance curves used to estimate water consumption
based on the steaming rate required to maintain the horsepower
outputs derived fr coal consumption estimates.
• 8AT consumption figures are conservatively estimated to be 80%
those of an equivalent size Chinese loco (JS type) hauling the
same load.
Economics of Modern Steam Traction in Transportation of Coal by Rail
Locomotive Cost Comparisons
Estimating Water Consumption
For Loaded Journey
Item
Gross train weight
Units
QJ
JS
8AT
tonne
3,720
3,162
3,162
Wheel rim TE at 50 km/h (see note)
kN
119
101
-
Wheel rim power at 50 km/h
kW
1,653
1,403
-
Steam consumption per hour per m2
kg
59
66
-
Heating surface area (excluding superheater)
m2
255.3
213
-
kg/hr
15,063
14,058
-
h
2.0
2.0
2.0
tonne
30
28
22
Steam production
Journey time over 100 km railway
Steam consumption
Note: The wheel rim TE values include a 100% load factor applied to train rolling
resistance values on straight level track to account for grades and curvatures.
Economics of Modern Steam Traction in Transportation of Coal by Rail
Locomotive Cost Comparisons
Estimating Water Consumption
For Empty Journey
Item
Units
Empty train weight
tonne
Wheel rim TE at 50 km/h (see note)
QJ
JS
8AT
920
782
782
kN
85
73
-
Wheel rim power at 50 km/h
kW
1,181
1,014
-
Steam consumption per hour per m2
kg
43
46
-
Heating surface area (excluding superheater)
M2
255.3
213
-
Steam production
kg/hr
10,978
9,798
-
Journey time over 100 km railway
h
2.0
2.0
-
Steam consumption
tonne
22
20
16
Note: The wheel rim TE values include a 100% load factor applied to train rolling
resistance values on straight level track to account for grades and curvatures.
Economics of Modern Steam Traction in Transportation of Coal by Rail
Locomotive Cost Comparisons
Estimating Annual Water Costs
Item
Units
QJ
JS
8AT
Steam consumption Loaded Journey
tonne
30
28
22
Steam consumption
tonne
22
20
16
Total water consumption per round trip
tonne
52
48
38
7,143
8.403
8,403
371,863
400,941
320,753
Number of round trips per year
Total Water Consumed
unit
tonne
Water cost including treatment
$/t
1.30
1.30
1.30
Total Water Cost including treatment
$m
0.483
0.521
0.417
Economics of Modern Steam Traction in Transportation of Coal by Rail
Locomotive Cost Comparisons
Estimating cost per kWh of energy output
for each traction type
Assumptions:
• Coal used is the NAR value for Lumut BA70 coal with NAR calorific value
of 6500 kg/kcal.
• Calorific value for diesel is an industry average of 10,200 kg/kcal;
• Representative drawbar thermal efficiencies used for each traction type;
• “Fuel consumption” of electric loco = kWh consumed ÷ kWh supplied;
• Electrical losses from the point of supply to the loco drawbar = 20%;
• Unit cost for electric power $0.08 per kWh and $700 per tonne for gas oil;
• Ex-mine coal price = $20 per tonne.
Note: Export coal price is not used because it includes costs of loading,
transportation, storage, blending, loading onto ship, plus profit, which do not apply
to coal used for locomotive fuel.
Economics of Modern Steam Traction in Transportation of Coal by Rail
Locomotive Cost Comparisons
Estimating cost per kWh of energy output
for each traction type
Units
Energy Conversion Factor
QJ
8AT
DF4
SS3
kcal/kW-h
860
860
860
-
Max Drawbar Thermal Efficiency
%
8%
15%
30%
-
Assumed Drawbar Thermal Efficiency
%
6%
10%
25%
80%
Fuel Calorific Value
Kcal/kg
6,500
6,500
10,200
Fuel Consumption
Kg/kWh
2.205
1.323
0.337
1.250
$/t
$20
$20
$700
$0.08
US cents
4.41
2.65
23.61
10.00
Fuel Cost per tonne
Cost of Fuel per kW-h of loco’s output
-
Economics of Modern Steam Traction in Transportation of Coal by Rail
Locomotive Cost Comparisons
Estimating Fuel Consumption for each traction type
Assumptions:
• Train rolling resistance calculated using Chinese formulae - viz:
RRF = 0.92 + 0.0048V + 0.000125V2 N/tonne for full wagons and
RRE = 2.23 + 0.0053V + 0.000675V2 N/tonne for empty wagons .
• At average train speed = 50 km/h, RRF = 15 kN/t and RRE = 42.6 kN/t;
• Arbitrary 100% “Load Factor” added to allow for trains stopping, starting,
climbing hills, braking when descending, and negotiating curves.
Economics of Modern Steam Traction in Transportation of Coal by Rail
Locomotive Cost Comparisons
Estimating Fuel Consumption for Loaded Journeys
Units
Gross train weight
Tonne
QJ
8AT
DF4
SS3
3,720
3,162
4,650
6,231
Specific rolling resistance full train
N/t
15
15
15
15
Rolling resistance (level track)
kN
55.8
47.5
69.8
93.5
Load factor for curves and grades
%
100
100
100
100
Rolling resistance (curved track)
kN
111.7
94.9
139.6
187.1
Power consumed overcoming resistance
kN-km/h
5,584
4,746
6,980
9,353
Power consumed overcoming resistance
kW
1,511
1,319
1,939
2,599
Kg/kWh or kW/kWh
2.205
1.323
0.337
1.250
kg/h or kWh/h
3,421
1,745
654
3,248
kg/km or kWh/km
68.4
39.4
13.1
65.0
t or kWh
6.84
3.94
1.31
5,500
18.39
11.04
2.81
10,426
Specific fuel consumption
Fuel consumption rate for loaded journey
Fuel consumption for loaded journey
Fuel consumed on loaded journey
Fuel consumption per million tonne-km
tonne/106 t-km
Note: Fuel consumption figures per 106 t-km are consistent with
Chinese statistical data – see next slide.
Economics of Modern Steam Traction in Transportation of Coal by Rail
Comparative figures - Steam vs. Diesel
from China National Railways
Year
Available
locos per
day
Train Gross
mT-km
(106 t-km)
Loco
Failures per
106 t-km
Av. Fuel
Consumption
per 106 t-km
(tonne)
Unit Price of
Fuel
($US/tonne)*
Fuel Cost of
Traction
$US/106 t-km
Steam
Diesel
Steam
Diesel
Steam
Diesel
Steam
Diesel
Steam
Diesel
Steam
Diesel
1987
5,317
3,282
770,009
750,090
3.0
11.0
11.09
2.59
24
367
267
951
1995
3,061
6,224
268,998
1,435,365
3.4
16.8
13.74
2.43
24
367
331
893
1999
1,013
7,825
32,475
1,682,046
0
13.1
20.66
2.62
24
367
497
962
2003
-
8,585
-
1,384,996
-
7.0
-
2.54
24
367
-
993
Notes: These figures are taken from official statistics of the Operating Department of
China’s National Railway, as published by State authorities in March 2004.
* “Unit Price of Fuel” figures do not include contemporary fuel costs;
2003 costs are used for comparative purposes (converted at RMB 8.3 per USD).
Economics of Modern Steam Traction in Transportation of Coal by Rail
Locomotive Cost Comparisons
Estimating Fuel Consumption for Empty Journeys
Units
Tare weight of empty train
QJ
8AT
DF4
SS3
T
920
782
1,150
1,541
Specific rolling resistance empty train
N/t
42.6
42.6
42.6
42.6
Load factor for curves and grades
%
100
100
100
100
Rolling resistance (curved track)
kN
78.4
66.7
98.1
131.4
Power consumed overcoming resistance
kW
1,090
926
1,362
1,825
kg/km or kWh/km
48.1
24.5
9.2
45.6
t or kWh
4.81
2.45
0.92
4,560
52.24
31.34
7.99
29,614
Fuel consumption for empty journey
Fuel consumed on empty journey
Fuel consumption per million tonne-km
tonne/106 t-km
Economics of Modern Steam Traction in Transportation of Coal by Rail
Locomotive Cost Comparisons
Estimating Fuel Costs per Annum
Units
QJ
8AT
DF4
SS3
Annual Tonnage Throughput
m.t
20
20
20
20
Distance hauled
km
100
100
100
100
2,000
2,000
2,000
2,000
Total net million tonne-km per year
m.t-m/y
Gross wagon weight
t
93
93
93
93
Net wagon weight
t
70
70
70
70
Ratio gross to net tonnes
-
1.33
1.33
1.33
1.33
Total million tonne-km per year (full)
m.t-km/y
2,657
2,657
2,657
2,657
Fuel consumption per million tonne-km
t or kWh
18.39
11.04
2.81
10,426
Total fuel consumed hauling full trains
t or kWh
48,871
29,322
7,474
27.7m
Total million tonne-km per year (empty)
m.t-km/y
657
657
657
657
Fuel consumption per million tonne-km
t or kWh
52.24
31.34
7.99
29,614
Total fuel consumed hauling empty trains
t or kWh
34,330
20,598
5,250
19.5m
Total fuel consumed - full and empty trains
t or kWh
83,201
49,921
12,725
47.2m
20
20
700
0.08
1.664
0.998
8.907
3.773
Cost of Fuel per tonne or kWh
Cost of Fuel per year of operation
$
$m
Economics of Modern Steam Traction in Transportation of Coal by Rail
Locomotive Cost Comparisons
Comparison of Overall Costs per Annum
Units
QJ
8AT
DF4
SS3
Amortized Cost of Locos and
servicing infrastructure:
$m
0.680
1.560
0.560
2.829
Total cost of maintenance per year
$m
0.795
0.763
0.962
0.586
Labour cost per year
$m
0.360
0.330
0.135
0.165
Total water cost including treatment
$m
0.483
0.417
nil
nil
Total fuel cost per year
$m
1.664
0.998
8.907
3.773
Total Operating Cost per Year
$m
3.983
4.069 10.564
7.353
Cost per tonne of freight hauled
$/t
0.20
0.20
0.53
0.37
$/mt-km
1,991
2,034
5,282
3,676
Cost ratio compared to QJ option
%
100%
102%
265%
185%
Cost difference compared to QJ
$m
-
0.085
6.581
3.370
Cost per million-net-tonne-km
Notes: 1: Electrical costs exclude maintenance of electrical infrastructure;
2: Extra capital cost of 8AT vs. diesel will be recovered within 3½ years.
3: 8AT costs are likely to be lower than those assumed in this study
Economics of Modern Steam Traction in Transportation of Coal by Rail
Locomotive Cost Comparisons
Sensitivity of Cost Assumptions on Cost Comparisons
Annual costs in $ million, taken from spreadsheet analysis
QJ
8AT
DF4
SS3
Calculated Operating Cost per Year from Table 21
3.983
4.069
10.564
7.353
Doubling of labour costs to $10,000 p.a.
4.343
4.398
10.699
7.518
Doubling of water cost to $2.60 per tonne
4.466
4.486
10.564
7.353
Doubling steam locomotive maintenance costs
4.777
4.831
10.564
7.353
Doubling steam loco and infrastructure capital cost
4.662
5.682
10.564
7.353
Doubling steam locomotive fuel cost (to $40 per t)
5.646
5.067
10.564
7.353
50% increase in price of diesel (to $1050 per t)
3.983
4.069
15.018
7.353
Notes: 1: Even with $25 per tonne “carbon tax”, the 8AT would remain cheaper than
other options (see later slide).
2: Diesel costs very sensitive to fuel prices, because they are largest component.
Diesel traction costs are likely to escalate much more rapidly than steam’s.
Economics of Modern Steam Traction in Transportation of Coal by Rail
Part 7
Environmental Considerations
1.
2.
3.
4.
CO2 emissions
Smoke emissions
Other considerations
Positive considerations
Economics of Modern Steam Traction in Transportation of Coal by Rail
Environmental Considerations
Carbon Emissions
• Coal-burning steam locos will inevitably generate more CO2 than diesels,
because of coal’s higher carbon content and steam’s lower thermal
efficiency;
• Coal-burning “modern steam” traction cannot compete with diesel in
terms of carbon emissions;
• A recent study by Brian McCammon has produced estimates of “carbon
dioxide equivalent” footprints for different traction types – see next slide:
Economics of Modern Steam Traction in Transportation of Coal by Rail
Environmental Considerations
Comparison of CO2-e Emission between Traction Types
when hauling a 2800 tonne train at 45 km/h over 100 km, taken from report by Brian McCammon
Item
Units
Fuel
Old Steam
Mod Steam
Electric
Sub-bituminous Coal
Diesel
Fuel Oil
Drawbar efficiency (assumed)
%
6
10
23
25
Average drawbar power (estimated)
kW
932
932
932
932
Drawbar energy output
kW-h
2071
2071
2071
2071
Energy input
kW-h
34,518
20,711
9,005
8,282
Energy input
GJ
124.3
74.6
29.8
32.4
Fuel net calorific value
MJ/kg
20.9
20.9
20.9
42.7
Mass of fuel burned
Tonne
5.6
3.4
1.5
0.6
Direct Emissions Factor
kg CO2-e/GJ
92.8
92.8
92.8
82.6
Fugitive Emissions Factor
kg CO2-e/GJ
1.9
1.9
1.9
11.8
Total Emissions Factor
kg CO2-e/GJ
94.7
94.7
94.7
94.4
tonnes of CO2-e
11.8
7.1
3.1
2.8
Total Emissions per tonne of fuel burned
t-CO2-e/t fuel
2.11
2.11
4.33
2.11
Total Emissions per tonne-km of haulage
gm - CO2-e
42.0
25.2
11.0
10.1
Total Emissions per unit of energy output
kg(CO2)/db-kWh
5.70
3.42
1.37
1.19
Total Emissions
Notes: 1: “CO2-e” = “CO2 equivalent”. Includes equivalent weight of CO2 of other greenhouse gases such as nitrous oxide and methane that
are released in the mining, processing, transportation and burning of the fuels;
2: Efficiency of electric traction includes power station and transmission losses as well as the railway’s local losses in the power distribution
system and locomotive.
Economics of Modern Steam Traction in Transportation of Coal by Rail
Environmental Considerations
Effects of a $25 CO2 Emissions Charge on Traction Costs
Fuel Consumption
Assumed cost of fuel
Units
QJ
8AT
DF4
SS3
Kg/kWh
2.205
1.323
0.337
1.250
20
20
700
0.08
$/t or $/kWh
CO2-e per tonne of fuel
t-CO2-e/t
2.11
2.11
4.33
2.11
CO2-e per tonne tax rate
$/t CO2-e
25
25
25
25
Carbon tax charge
$/t of fuel
53
53
108
53
$ per t or $ per kWh
73
73
808
0.10
16.04
16.04
27.26
13.01
Effective fuel cost (including tax)
Cost of energy input (including tax)
cents per kWh
Economics of Modern Steam Traction in Transportation of Coal by Rail
Environmental Considerations
Effects of a $25 CO2 Emissions Charge on Traction Costs
Units
QJ
8AT
DF4
83,201
49,921
12,725
47.2m
73
73
808
0.10
$m
6.053
3.632
10.284
4.908
Total Amortization Cost of Locos and infrastructure:
$m
0.680
1.560
0.560
2.829
Total cost of maintenance per year
$m
0.795
0.763
0.962
0.586
Labour cost per year
$m
0.360
0.330
0.135
0.165
Total water cost including treatment
$m
0.483
0.417
nil
nil
Total Operating Cost per Year
$m
8.371
6.701
11.941
8.488
Cost per tonne of freight hauled
$/t
0.42
0.34
0.60
0.42
$/mt-km
4,186
3,351
5,971
4,244
Total fuel used per round trip (from Table 20)
t or kWh
Cost of Fuel per tonne or kWh (from Tbl 24a)
$
Cost of Fuel per year of operation
SS3
From previous cost table:
Cost per million-net-tonne-km
Cost ratio compared to QJ option
%
-
80
143
101
Cost difference compared to QJ
$m
-
-1.669
3.570
0.116
Note: 1: the 8AT is still clearly cheaper than all other traction options.
2: By the time a $25 per tonne carbon tax is applied to developing countries, the cost of oil is likely to
have risen substantially.
Economics of Modern Steam Traction in Transportation of Coal by Rail
Environmental Considerations
Comparison of CO2-e Emission between Traction Types
when hauling a 2800 tonne train at 45 km/h over 100 km, taken from report by Brian McCammon
Item
Units
Fuel
Old Steam
Mod Steam
Electric
Sub-bituminous Coal
Diesel
Gas Oil
Drawbar efficiency (assumed)
%
6
10
23
25
Average drawbar power (estimated)
kW
932
932
932
932
Drawbar energy output
kW-h
2071
2071
2071
2071
Energy input
kW-h
34,518
20,711
9,005
8,282
Energy input
GJ
124.3
74.6
29.8
32.4
Fuel net calorific value
MJ/kg
20.9
20.9
20.9
42.7
Mass of fuel burned
Tonne
5.6
3.4
1.5
0.6
Direct Emissions Factor
kg CO2-e/GJ
92.8
92.8
92.8
82.6
Fugitive Emissions Factor
kg CO2-e/GJ
1.9
1.9
1.9
11.8
Total Emissions Factor
kg CO2-e/GJ
94.7
94.7
94.7
94.4
tonnes of CO2-e
11.8
7.1
3.1
2.8
Total Emissions per tonne of fuel burned
t-CO2-e/t fuel
2.11
2.11
4.33
2.11
Total Emissions per tonne-km of haulage
gm - CO2-e
42.0
25.2
11.0
10.1
Total Emissions per unit of energy output
kg(CO2)/db-kWh
5.70
3.42
1.37
1.19
Total Emissions
Notes: 1: “CO2-e” = “CO2 equivalent”. Includes equivalent weight of CO2 of other greenhouse gases such as nitrous oxide and methane that
are released in the mining, processing, transportation and burning of the fuels;
2: Efficiency of electric traction includes power station and transmission losses as well as the railway’s local losses in the power distribution
system and locomotive.
Economics of Modern Steam Traction in Transportation of Coal by Rail
Environmental Considerations
Smoke Emissions
• Steam locos in good condition do not normally emit large quantities of
“nuisance” smoke when operating;
• Modern steam locos with GPCS fireboxes should emit less smoke
because of more complete combustion;
• Smoke nuisance is normally limited to large locomotive storage sheds
when located near residential areas. Not likely to be a problem for a
railway with only 12 locos operating 24 hours a day (i.e. not put into
storage at night).
Economics of Modern Steam Traction in Transportation of Coal by Rail
Environmental Considerations
Smoke Emissions
• Chinese locos are renown for
smoke-free operation.
• Diesels are not smoke-free
Economics of Modern Steam Traction in Transportation of Coal by Rail
Environmental Considerations
Other Considerations
• Ash disposal;
• Treatment of high pH water disposal after boiler washes;
• Disposal of waste lubricant disposal before overhauls;
• Controlling coal dust during refuelling operations;
• Controlling coal smoke inside workshop buildings.
Economics of Modern Steam Traction in Transportation of Coal by Rail
Environmental Considerations
Positive Considerations
•
Steam engines can generate carbon-neutral power through combustion
of any form of bio-fuel (solid or liquid). Steam engines (stationary or
mobile) have commonly burned carbon-neutral fuels including wood
and agricultural waste products like bagasse and rice husks;
•
McCammon’s research shows that a coal-fired 8AT will produce only 2½
times more CO2 than diesel or electric traction. Further development
will see its carbon footprint reduced much further;
•
Improvements can only be achieved through investment in research
and development. Re-establishment of steam traction for coal haulage
may provide an incentive for further development of the technology.
Economics of Modern Steam Traction in Transportation of Coal by Rail
Potential Development Path for
Modern Steam Traction
Further development opportunities include:
• Pulverized coal for improved combustion and automated firing;
• Steam Condensing;
• Steam Turbine Generator with Electric Drive;
• Regenerative Braking.
Benefits will include:
• Lower manning levels (competitive with diesel traction)
• Thermal Efficiencies >20% (competitive with diesel traction)
• Lower carbon emissions (competitive with diesel traction).
Economics of Modern Steam Traction in Transportation of Coal by Rail
Potential Development Path for
Modern Steam Traction
“Garratt” formation with central boiler, twin engine units and end-cabs
Economics of Modern Steam Traction in Transportation of Coal by Rail
Part 8
Benefits of adopting Steam Traction
to Local Communities
1.
Tourism Opportunities: Steam locos attract tourists;
2.
Employment Opportunities: Steam employs more people
both for operating and servicing;
3.
Business Opportunities: Steam parts can be made by
local manufacturers. So too can locomotives, offering a
export possibilities to other coal producing countries .
Economics of Modern Steam Traction in Transportation of Coal by Rail
Part 9
Conclusions
1.
Steam traction is a technically viable option for freight haulage, especially
where gradients are not steep;
2.
Steam traction is (by a substantial margin) the most cost-competitive option
for haulage of coal where coal and labour costs are low;
3.
Steam’s cost advantage is insensitive to large changes in cost assumptions;
4.
Diesel’s costs are highly sensitive to increases in fuel costs which are likely
to occur in the future;
5.
Modern steam offers the lowest operating costs, and its cost advantage will
increase as fuel and labour costs rise.
6.
Steam’s cost advantage is enhanced by the smaller wagon fleet that is
needed, and by haulage of shorter trains;
7.
Further study is needed in some areas to more clearly define the design
requirements for a steam-driven railway system (see next slide).
Economics of Modern Steam Traction in Transportation of Coal by Rail
Conclusions
Recommendations for Further Study
1.
Railway’s Efficiency: If the assumed efficiency (75%) is too high, it will affect
train sizes, loops siding spacing, and rolling stock requirements (but not
enough to affects steam’s cost supremacy);
2.
Fuel and Water Consumption need more detailed analysis based on the
actual grades and curvature of the railway. If locos have to be refuelled at
both ends of the line, then the project design needs to allow for
transportation of loco fuel to the unloading station.
3.
Flow Properties of Export Coal must be undertaken if any consideration is
given to use of bottom-dump wagons. The type of wagon and unloading
system affects the turn-around time of trains and therefore the locomotive
(and wagon) fleet requirements.
4.
Locomotive Servicing needs more detailed analysis to determine servicing
times that can be reliably achieved. Servicing time affects the turn-around
time of trains and therefore the loco fleet numbers.
Economics of Modern Steam Traction in Transportation of Coal by Rail
Conclusions
Supplementary Recommendations
1.
Ruling Gradient of Railway: It is strongly recommended that where
economically practical, the ruling gradient of any steam operated
railway should not exceed 0.5% (1 in 200). Because of their limited
adhesion, steam locomotives do not climb well.
2.
Coal Quality: The calculations in this study imply that locomotive fuel
consumption is directly related to the CV of the fuel. Whilst this is
true in theory, in practice fuel consumption increases exponentially
as coal quality declines. It is of utmost importance that the best
available coal (high CV; low ash; high volatiles; low moisture; lump
coal with few fines) be reserved for locomotive fuel.
Economics of Modern Steam Traction in Transportation of Coal by Rail
Conclusions
New Steam Locos can be built in 21st Century
Switzerland
UK
South Africa
End
Sincere thanks to:
•
•
•
•
Malcolm Cluett (Australia)
Brian McCammon (New Zealand)
Alan Fozard and John Hind (UK)
Hugh Odom (USA)
Feb 2008