The document evaluates the energy efficiency of railway transportation compared to electric and diesel vehicles, highlighting the advantages of electric traction in terms of energy recovery and reduced power demand. It provides a detailed comparison of electric and diesel locomotives, emphasizing the superior performance and efficiency of electric trains. Moreover, it points out the significant potential for energy savings and environmental benefits through the increased electrification of railway lines.

1. How energy efficient really is
railway transportation?
Stefan Fassbinder
Deutsches Kupferinstitut
Am Bonneshof 5
D-40474 Düsseldorf
Tel.: +49 211 4796-323
Fax: +49 211 4796-310
sfassbinder@kupferinstitut.de
stf@eurocopper.org
www.kupferinstitut.de
www.leonardo-energy.org

2. The German Copper Institute, DKI, is
the central information and advisory
service dealing with all uses of copper
and copper alloys.
We offer our services to:
 Commercial companies We can be contacted by:
 The skilled trades  post
 Industry  phone
 R & D institutes  fax
 Universities  e-mail
 Artists and craftsmen  internet
 Students  online database, or
 Private individuals  personally

3. Does electricity boost mobility?
Electric cars are
• technically not feasible for long distances,
• economically not viable for short distances.
To charge up a laptop PC
• costs 1 cent for electricity from the socket.
• The battery costs 90 € and survives 1000 duty cycles.
• This means:
10 times higher energy price while battery powered!
With big units for vehicles the factor still is around 3.
The »tank« of an electric car
• costs 3000 €/l, converted to energy equivalent diesel
• weighs 30 kg/l
} fuel quantity (ηD = 30%, ηE = 90%)
• and is over and done with after 1000 … 3000 fillings.

4. But still the trade press
wanted it yet another time:
»Market introduction of electric cars to
start in 2011«

5. Comparison: Citroën C-Zero Citroën C1
(electric) (petrol engine)
Length 3480 mm 3430 mm
Width 1475 mm 1630 mm At least one thing is
Height 1792 mm 1470 mm certain:
Empty mass 1195 kg 925 kg
Payload 255 kg 265 kg  These vehicles are
Luggage volume 166 l 139 l really comparable.
Turning circle 9.0 m 9.5 m  This is a real electric
Drive back front car in its own right!
Gears (forward) 1 5
 Only the payback –
Power rating 49 kW 50 kW
even without fuel tax
Top speed 130 km/h 157 km/h
– takes 469,000 km!
Acceleration 15.9 s 13.7 s
Cruising range 150 km 760 km  This corresponds to
CO2 emissions 100 g/km 107 g/km 3,000 charging
Energy costs 2.20 €/100 km 6.90 €/100 km cycles – the end of
Purchase price 35,165 € 13,120 € the battery lifetime…

6. Electricity does boost mobility!
If only there is a way to bring the power into the vehicle
Electric motors
• have their highest torque at standstill:
No disengaging, no gearchange, no torque converter
required,
• provide a considerable short-term overload capability:
Higher acceleration than the power rating would let you
suppose,
• do not have any no-load consumption during standstill,
rolling or braking,
• offer the opportunity to feed back energy during braking
(motor = generator),
• and their primary fuel is totally flexible (fossil, nuclear,
hydro, wind – just mix as you like!).

7. So it is not a miracle
if railway companies prefer
electric traction!
Characteristic data of 16.7 Hz railways
Electricity system of DB AG
in D-A-CH
Installed Energy
Type of power plant DB AG ÖBB SBB
capacity production
Vapour 42.2% 66.0% Employees 240242 42893 27822
Hydro 11.0% 10.0% Passengers 1919Mio. 200Mio. 332Mio.
Railway grid
Rotating convertor 34.3% 14.6% total 33862km 11000km 3011km
Electronic convertor 11.9% 9.4% electrified 19300km 8200km 3011km
share
Total 3.2GW 11.0TWh/a of lines 57% 75% 100%
Sum of all electric vehicles 22.4GW (700%) of transport 85% 100%
volume
56% of DB lines are
… since the energy electrified. These 56% carry
“consumption” of an electric 85% of all traffic.
locomotive can be negative! However …

8. …what about the other 15%?
e. g. the
612 series?
• Engine power rating: 2*560 kW = 1120 kW
• Smart and convenient:
Tilting technique, air conditioning
• Maximum permissible speed: 160 km/h
• Fuel consumption: 1.7 l/km (for one, not 100 km!)

9. What about diesel locomotives?
• On a series 232 diesel locomotive (6 axles, 120 t,
2,200 kW, max. 120 km/h) at a constant speed of
120 km/h a consumption of 3 l/km was measured.
• (for good resons railway companies reference the fuel consumptions to
one kilometre, not to 100 kilometres!)
• There have not been any new diesel locomotives for decades.
• There are old diesel locomotives with new engines.
•BR 232 “Ludmila” is then >40%.
The engine efficiency BR 220 “Taiga Drum”
• But what„s the use of this if the engine is idling for >90% of its operating
time?
• And if a DB technician explains: “Diesel locomotives hamper the traffic
when circulating on an electrified line!” …
• …and if a railway trade journal reports the electrification of a line no
longer than 22 km had already cut the circulation time by 5 minutes?
„Elektrischer Betrieb bei der Deutschen Bahn im Jahre 2009“. „eb“ Elektrische Bahnen & Verkehrssysteme 1-2/2010, p.19

10. However, the 101 series electric loco
(4 axles, 84 t, 220 km/h) provides a
motor power rating of 6,600 kW!
Note: It„s electricity that wakes trains up!

11. This explains it:
800kW/t
Inverse trends!
600kW/t
Power density of reciprocating
combustion engines
Power density →
400kW/t Power density per size of
respective electric motors
200kW/t
Power rating →
0kW/t
1kW 10kW 100kW 1000kW 10000kW 100000kW

12. The parameters responsible for
the energy demand are
(at ≈200 km/h): of a car of a train factor
(4…5 seats)(450 seats) 100
Mass 1.5 t 450 t 300
Coefficient of staticare a means of mass transportation! 0.3
Note: Trains friction ≈1 0.28…0.35
Coefficient of rolling friction ≈2% <2‰! 0.1
Resulting: some good reasons railwaykN
Note: For Rolling friction force 0.3 companies give rolling
9 kN 30
Power demand resulting from as per kW figures!
friction coefficients this 15 mille 450 kW 30
as a share of power rating 15% 7% 0.5
Air friction force 1.5 kN 30 kN 20
Power demand resulting from this 85 kW 1550 kW 18
as a share of power rating 85% 23% 0.27
Total power demand 100 kW 2000 kW 20
as a share of power rating 100% 30%! 3.3

13. Now what are the other
70% of power good for?
Compared to a car, a train has:
- A very great mass.
- Significantly less static friction
(steel on steel rather than rubber on asphalt).
+ Significantly less rolling friction
(steel on steel rather than rubber on asphalt).
+ Significantly less air friction (since the train
travels “in its own windshade”, so to say).

14. On rails even a »Unimog« universal
miniature lorry can haul 1000 t!
Though not at a particularly high speed

15. Worth noting:
The top speed
of a car is usually of a railway vehicle
the highest is usually the
possible highest
speed, limited by permissible
the available speed.
engine power.

16. With a great deal of good will
66kW 6,6MW
we will now requirement car anda train
Power let a car with IC
•55kW kW engine and (very tight) space for
66 P (car) 
5,5MW
P (IC train) 
•44kW
4 passengers travel at 4,4MW
•33kW km/h, P (car)
200 3,3MW
P (IC train)
while a train with a drive power rating of
22kW 2,2MW
• 6,600 kW offers plenty of space to
•11kW passengers (including toilets, a
400 1,1MW
bistro, …). At a travelling speed of 0,0MW
0kW
v 
• 200 km/h50km/h requires: 150km/h 200km/h
0km/h
this 100km/h

17. But a car accelerates faster?
100%
90% v/vmax 
80%
70% Well, initially process the
Acceleration yes, but
train has a lot of reserves!
car and train (0 … 200 km/h)
60%
50%
40%
Car acceleration v/vmax
30%
IC train (10 carriages) v/vmax
20%
10%
0%
0km 1km 2km 3km 4km 5km s 
6km 7km 8km

18. Quiz question 1:
How far will an ICE2 express
train of the 402 series continue to roll
unbraked in a flat area when suddenly
the power fails at a speed of 230 km/h?
Answer 1:
The test was not carried out all through
to the end. After 32 km the train was still
rolling at 120 km/h!

19. Quiz question 2:
How fast will a railway carriage
become when you let it roll down a
decline of 5‰ (just 0.5%!)?
Answer 2:
Note: For some good reasons railway
companies give inclines and declines
According to technical documents by as
per mille Bahn AG
Deutsche figures! it will (finally) reach
a speed of 44 m/s ≈ 160 km/h (after
1 hour of rolling)!
A street car would simply just stall and not roll at all!

20. Quiz question 3:
Why is it that in a train repair
hall which can be opened at both ends
it is not allowed to leave both gates
open at the same time?
Answer 3:
Because the wind might blow the
locomotoves out of the hall!

21. So let’s just accelerate a
200km/h
fully occupied street car
v 
to 200 km/h, disengage
150km/h
and see what will
happen…
100km/h
Mass: Train rolls kg
2000
Train rolls
Train brakes
Car rolling out
Rolling friction coefficient: Car rolling out
50km/h
2%
Car rolling out
Front surface area: 2 m²
cx value:
0km/h 0.37
2km s 
Engine power: 1km
0km
105 kW 3km

22. Adapting the scale to the train:
200km/h
Rolling and braking:
v 
Express train (10 carriages)
versus car
150km/h
100km/h
Train rolls
Train brakes
Car rolling out
50km/h
s 
0km/h
0km 5km 10km 15km 20km 25km

23. Adapting the scale to the train:
200km/h
Rolling and braking:
v 
Express train (10 carriages)
versus car
150km/h
100km/h
Train rolls
Train brakes
Car rolling out
50km/h
t 
0km/h
0s 120s 240s 360s 480s 600s

24. Hauling force and power
IC fast train with DB's 101
300kN series locomotive and 6MW
9 carriages
250kN 5MW
Hauling force 
Power 
200kN 4MW
150kN 3MW
Required hauling force
Required power
100kN 2MW
50kN 1MW
Speed 
0kN 0MW
0km/h 50km/h 100km/h 150km/h 200km/h

25. Hauling force – 80% left?
IC fast train with DB's 101
300kN series locomotive and 6MW
9 carriages
250kN 5MW
Hauling force 
Power 
200kN 4MW
150kN 3MW
Required hauling force
Available hauling force
100kN 2MW
Required power
50kN 1MW
Speed 
0kN 0MW
0km/h 50km/h 100km/h 150km/h 200km/h

26. Power – 70% left?
IC fast train with DB's 101
300kN series locomotive and Power limit 6MW
9 carriages
250kN 5MW
Static friction limit 
Hauling force 
Power 
200kN 4MW
150kN 3MW
Required hauling force
Available hauling force
100kN 2MW
Required power
Available power
50kN 1MW
Speed 
0kN 0MW
0km/h 50km/h 100km/h 150km/h 200km/h

27. Not while running uphill!
IC fast train with DB's 101
300kN series locomotive and 9 6MW
carriages running up
Power 
250kN an 18.5‰ incline
5MW
Hauling force 
When it becomes steeper
200kN than that the top speed 4MW
cannot be held any more
150kN 3MW
100kN 2MW
Required hauling force
50kN Available hauling force
1MW
Required power
Available power
0kN 0MW
0km/h Speed 
50km/h 100km/h 150km/h 200km/h

28. At 300 km/h, however …
300kN 8MW
ICE3 high speed railcar
of DB's 403 series 7MW
250kN
… the demand does 6MW
F 
200kN increase rapidly  5MW
150kN 4MW
P 
Required hauling force
3MW
100kN Available hauling force
Required power 2MW
50kN Available power
1MW
v 
0kN 0MW
0km/h 100km/h 200km/h 300km/h

29. The ultimate train concept
330km/h ICE3 high speed railcar 0,75m/s²
a 
300km/h of DB's 403 series
270km/h 0,60m/s²
240km/h
210km/h 16 out of 32 axles driven 0,45m/s²
180km/h
v 
by a 500 kW motor each
150km/h provide optimal
0,30m/s²
120km/h acceleration and
90km/h energy recovery
60km/h 0,15m/s²
Speed
30km/h Acceleration
s 
0km/h 0,00m/s²
0km 5km 10km 15km 20km 25km

30. The ultimate train concept
330km/h ICE3 high speed railcar 0,75m/s²
a 
300km/h of DB's 403 series
270km/h 0,60m/s²
240km/h
210km/h 16 out of 32 axles driven 0,45m/s²
180km/h
v 
by a 500 kW motor each
150km/h provide optimal
0,30m/s²
120km/h acceleration and
90km/h energy recovery
60km/h 0,15m/s²
Speed
30km/h Acceleration
t 
0km/h 0,00m/s²
0s 60s 120s 180s 240s 300s 360s

31. Also you have to accelerate the train to
the desired travelling speed of 300 km/h
(83.3 m/s) first in order to run that fast
With a 4% supplement for rotating masses and an efficiency
of 87%, measured at the pantograph, this makes about
520 kWh for one single acceleration from 0 to 300 km/h.
With the DB tariff of 9 c/kWh this costs approximately 47 €!
It would be pretty sad to get nothing of this back at all.
Counted with an efficiency of 87% again, you can retrieve
75% during brakage – if all goes well.
2
m 450,000kg m
Wkin * v² * 83.3 1.56 *109 Nm 1.56GJ 434kWh
2 2 s

32. Bad outlook for the diesel
Electric traction turns out to be far superior:
• Power density and dynamic behaviour are outstanding.
• 9% of all electricity consumed by locomotives in Germany
has been used once before by another locomotive and fed
back again into the supply system.
• Usually this works only with water (or e. g. copper!) but
never ever with coal, gas and oil.
• The share will continue to grow, since by and large more
and more old electric locos without feedback capability are
being replaced with modern power electronic ones.
• But we will still have to wait for a long time to see a diesel
engine coming around that, when braking, sucks up fumes
and converts them back into fresh air and fuel.

33. Electric power speeds us up!
• For 2009, DB„s department for Energy Cost Management
gives an average circulation of 347,620 km for each of their
145 locomotives of the 101 series.
• The average consumption is ≈17 kWh/km (including
electricity the locomotive has fed into the train for heating
the carriages and for ancillary supplies).
• This yields an electricity cost of half a million Euros per
year.
• The purchase price of the 101 series is around 3 million
Euros.
• So for the power consumption of a locomotive„s 30-year-
long life you could buy in 5 complete locomotives!
• 9% of energy fed back saves 1.2 million Euros per loco
during 30 years!

34. Or let’s have a look at
suburban transportation
The regional train from Aachen to Dortmund
travels about 160 km far, calling 22 times.
Its top speed is 140 km/h.
If it went all through non-stop, it would consume
only 800 kWh for overcoming the friction.
But accelerating 22 times costs 1600 kWh!
So this is 2/3 of the overall energy consumption!
Hence, in theory about 3/4 out of 2/3, say half of the
energy, could be recovered, but unfortunately …

35. Or let’s have a look at
suburban transportation
… according to DB Regio the real rate of recovery
is only 10% in this business unit!
And now what to do? What’s the deficiency?

36. Hence DB’s plans for the
coming decades are:
• Increase the share of inverter
locos from 47% (2009) to 100%: 10% → 20%
• Improve control infrastructure –
no more odour of hot brakes: 20% → 50%
• Replace all Loco-and-carriage
trains with railcars: 50% → 60%
• Railcars are lighter and hence use less energy
• The dispersed drive expands the opportunities
for energy recuperation

37. Not fragile …
Stock of drive vehicles with DB AG
4000
3500
Number 
Drive vehicles with feedback capability
3000 Tap changer regulated drive vehicles
2500
2000
1500 Tap changer operated vehicles
1000 have no longer been commissioned
500 already since 1985, but still…
0
2007 2009 2010 Year  2011

38. If you see a tap-changer
controlled locomotive today
then it is most likely to be 36 years old.
In case of the 110 series, for
instance, this vehicle must be between
42 and 54 years old!
And it still keeps on running …

39. Old tap-changer vehicles
still on duty with DB AG
Stock BR supplied 2007 2009 2010 2011 Age
Locomotives 103 1972 to 1974 3 3 3 37a to 39a
Tap changer regulated drive vehicles
DB Long 113 1962 to 1963 115 2 3 3 48a to 49a
Distance 115 1962 to 1964 28 19 17 47a to 49a
110 1957 to 1969 109 88 64 42a to 54a
111 1975 to 1984 225 225 224 27a to 36a
Locomotives Legacy to 1993
112 1992 from 1115 89 89 89 18a to 19a
DB Regio
114 the GDR
1990 to 1992 40 39 38 19a to 21a
143 railways1990
1984 to 556 520 487 21a to 27a
Railcars 420 1969 to 1994 189 167 163 17a to 42a
205
DB Regio 450 4 4 4
Locomotives 140 1957 to 1973 172 74 81 38a to 54a
DB Schenker 151 1973 to 1975 648 163 140 133 36a to 38a
Rail (freight) 155 1974 to 1984 219 195 185 27a to 37a
Sums Locomotives 1877 1606 1395 1324 33a 36a 40a
resp. Railcars / integr. trains 205 193 171 167 17a 30a 42a
mean values Total 2082 1799 1566 1491 25a 33a 41a

40. Now what„s up with
the 44% of lines
without a trolley wire?
• There is a diesel railcar standing at the railway station. There are 2
engines mumbling under no-load conditions inside it – and are being
cooled, while an oil heater fuelled with diesel fuel at the price of diesel
fuel is heating the passenger cabin.
• The railcar starts. The engines raise their voices a little bit.
• Only above some 30 km/h … 60 km/h the full power can be transmitted
to the rails: Now the engines hum a bit more vigorously – for about one
minute. Then the top speed has been reached. About 30% of the
engine rating suffice to sustain a constant speed of 160 km/h.
• But very soon we are approaching the next station. The railcar is kept
rolling for several minutes, the engines disengage, mumbling calmly.
• Then the railcar brakes. The engines rev up – just to dissipate the
heat from the hydraulic braking system via the engine radiators!
Is this a concept for the future? – Or rather a makeshift solution?

41. But wasn‘t there something else?
Oh, right: The 515 series!
• Accumulator-operated railcars
have been in use since 1907!
• for 40 years, from 1955 to 1995, well over 220
motor vehicles of the 515 series have been in use:
• Power rating 2*150 kW
• Maximum speed 100 km/h
• 10 t … 16 t of lead accumulators
• Capacity 352 kWh … 602 kWh
• Cruising range 300 km

42. Mental experiment:
A modern re-issue
• Today„s Li ion accumulators provide 4 times the
energy density of the old lead acid batteries, so:
• you can double the capacity while halving the
mass.
• Doubling the capacity doubles the cruising range
to about 600 km.
• halving the weight along with the use of modern
inverter technique with generative brakage im-
prove the performance (min. 140 km/h) and the
comfort (e. g. air conditioning).

43. Comparing a hypothetical electric
battery railcar to a street car
Tesla Electric
Roadster railcar
Energy capacity 55 kWh 1100 kWh
Energy demand 200 Wh/km 2000 Wh/km
Energy demand per seat 100 Wh/km 10 Wh/km
cruising range 350 km 600 km
Battery mass 0.45 t 9t
as share of the vehicle 36% 12%
Battery price 45.000 € 900.000 €
as share of conv. vehicle 50% 25%

44. How much really is the
electricity from the battery?
Battery price: 900.000 €
Life time: 3000 cycles
Energy capacity: 1100 kWh
So in effect the power from the battery costs:
Electricity taken from trolley wire 90 €/MWh
Charge cycle / conversion losses +10 €/MWh
Night tariff rebate -10 €/MWh
Wear of the accumulator battery +270 €/MWh
Electricity cost from the battery 360 €/MWh

45. Comparison to the existing
series 612 diesel railcar
Diesel railcar Batt. railcar
Primary energy demand 20 kWh/km <6 kWh/km
Secondary energy demand 17 kWh/km 2 kWh/km
(1.7 l/km)
Net energy price 1.03 €/l 0.09 €/kWh
Energy price from the battery – – – 0.36 €/kWh
Net energy cost 1.80 €/km 0.18 €/km
Energy cost incl. battery – – – 0.72 €/km
At 250,000 km/a 450,000 €/a 180,000 €/a
During a 30 years„ life 13,500,000 € 5,400,000 €

46. Comparison to the existing
series 612 diesel railcar
The comparison is biased?
It is, but towards which side?
Note:
• The battery railcar will need at least 2 new
batteries during its 30-year service life
But:
• Diesel driven trains require 3 times as much
maintenance costs as electric trains do
So there is scope enough for 2 new batteries!

47. Alternative 1: Accumulator
railcar with pantograph
Local trains often leave
the city centres on
electrified lines and turn
off onto the seconday
lines only a bit later on.
Here the vehicles could
• be charged up during ride
• in part be driven as conventional electric railcars
with pantograph (»pop-up hybrid«)
• and thus require only a fraction of the (expensive)
battery capacity.

48. Alternative 2:
Hybrid diesel railcars
Do not confuse with the principle of the diesel-
electric locomotive! Since this is an electric locomotive lugging around
its own power plant.
• With the hybrid railcar, however, the diesel engine has only some 10%
of the electric power (e. g. a 66 kW car engine instead of 2*315 kW
railway engines).
• For the diesel engine is always running at the optimal point of operation
(rated speed and power) instead of idling ≈90% of its time.
• Also the generator rating is only 10% that of the electrical traction
power.
• The battery provides 90% or bears 110%, respectively, of the electrical
traction power during acceleration and brakage, respectively.
• Continuous heat generation. Combined heat and power generation
replaces the oil heater.
• Facilitates combination with alternative 1.

49. Hybrid diesel railcars – also
for long-distance fast trains?
Just take a trip from Berlin to Copenhagen!
There they are using up the unfortunate series 605 now.
• These railcars are equipped with diesel-electric drives, so
these already avail of electric drive motors and inverters.
• These trains arose on the platform of the 415 series 5-
carriage electric railcar!
• They had been withdrawn from service for several years.
• They were offered abroad for sale, but nobody wanted
them.
• One of the reasons given for the latter two points are high
fuel costs.
So why not convert these trains first?

50. Series 605 – ICE without pantograph
Just consider:
• Here the train does not run very fast and rarely stops.
• Still the fuel consumption lies around 3 l/km!
• This costs around 1800 € per single trip.
• For this alone 7 full-charge or 45 low-cost ticket passengers
will have to be sitting on the total of 195 seats.
• Whereas the major share of the easement is electrified!
• And for one hour the train is not travelling at all but is
standing on a ship.
So why not
• remove 3 of the 4 diesel engines and generators,
• replace them with accumulator batteries,
• possibly add a pantograph and a transformer
• but in any case reduce the fuel consumption by 1 l/km
• and save about 600 € of fuel cost on one trip?

51. Summary and conclusions
• Electric railway drives clearly outperform diesel
engines.
• At the same time electric railway drives are way more energy efficient
than diesel traction is.
• SBB operate 100% electrically – nothing left to do.
• E. g. DSB are 27% electrified – need for action!
• DB AG operate 85% electrically – this is fine so far.
• For the remaining 15% a re-introduction of battery operated railcars
based on modern lithium ion cells should be considered. 40 years of
good experinece even with lead acid accumulators support this idea.
• The economic viability of electric cars lies about 10 times further
away from reality than that of the battery operated railway vehicle!
The German Department of Technology and the EU Commission
should urgently take this into consideration with their energy efficiency
support programmes.