This document discusses energy conservation opportunities in railway coach lighting and air conditioning. It begins by introducing the electric loads in coaches and the need for lighting and air conditioning. It then describes the unique design challenges of air conditioning in coaches compared to buildings. The document outlines different coach classification systems and existing air conditioning and power supply arrangements. It evaluates the merits and limitations of various power supply systems and discusses the potential for improving lighting efficiency through use of more efficient bulbs and fixtures. In summary, the document performs an analysis of energy use in railway coaches and identifies technical approaches that could reduce energy consumption and costs.

1. Energy conservation in lighting and air-conditioning
of Railway coaches
MAULANA AZAD NATIONAL INSTITUTE OF
TECHNOLOGY, BHOPAL
DEPARTMENT OF ENERGY

2. contents
• Introduction
• Classification of train services.
• Different supply systems and their
comparison
• Different lighting systems and energy
consumption patterns
• References

3. Introduction
• Electric loads in railway coaches
• Need and concept of train lighting
• Need of air conditioning
• History and present state of art

4. Difference between air conditioning in
commercial and residential buildings and
railway coaches
• Equipments should be highly reliable, light
weight
• Available power is to be utilized
• Lesser space for air circulation
• Rapidly changing ambient conditions
• Excessive vibration

5. Contd…
• Exposure to direct sun
• Dusty atmosphere
• Flying ballast may hit the equipment
• Vandalism and abuse
• Safety of passenger and trains
• Restricted time available for maintenance

6. Systems of available air
conditioning plants
1. Roof mounted type
plants -
air conditioning plants
on the roof

7. 2. Under slung type plant
air
conditioning plants at
under frame of bogie.

8. Classification of train services
• A broad classification
1.Broad Gauge All air conditioned
coaches(rajdhani/shatabdi/garib rath exp.)
2. Broad Gauge AC and non AC coaches
(different mail and express trains)
3. Broad Gauge Non AC coaches (other
trains)
4. Meter Gauge AC and non AC coaches

9. Depending upon berth capacity
• I-AC
• II-AC
• III-AC
• Sleeper
• General

10. Depending upon power supply
arrangement
• End On Generation System (EOG)
• Self Generating System (SGU)
• Mid On Generation System (MOG)
• Head On Generation System (HOG)

11. End On Generation System
• Power fed at 750 volts from two generator
car attached at both ends having two DG
sets of 336 KW rated capacity
• Supply to the coaches is through two
independent feeders, each designed for a
maximum 250 amperes.
• In the coaches 750V, 3 phase AC is stepped
down to 415V through 415kVA delta/star
transformer

12. •All AC plants and WRA work on 415V,
whereas pantry car equipment work on 230V.
.With present system of EOG, a max. of 6
coaches can be fed through one DG set under
peak load condition
.A 24V Emergency battery of 90 Ah capacity
has been provided on the under frame along
with a battery charger to supply emergency
lights in the coach in the case of power failure

13. Merits an Demerits of EOG system
• MERITS:---
• System is independent of mode of traction
• Elimination of bulky batteries and alternators
reduce dead weight and maintenance
• System has high reliability due to cent percent
standby system
• High capacity power cars are developed, each
giving 2500kVA

14. • DEMERITS:---
• Cost of energy is almost double due to
higher fuel cost
• Noise and smoke pollutions
• Voltage drop
• Commercial space reduced
• Requirement of more staff to operate and
maintain

15. Self Generation System
• Power is derived from the alternator mounted on
the bogie transform of the coach, driven by the
axle through ‘V’ belt drive.
• The 3 phase output from the alternator are brought
out by means of conduit to the box of rectifier cum
regulator suspended from under frame to give
output of 18KW at 130V DC.

16. Contd..
• Rectifier regulator may be transistor controlled or
magnetic amplifier type,and the facility exists for
controlling the DC o/p voltage, usually set at
128V,the setting has to be chosen to suit a
particular service by field trials
• One alternator set per AC plant is fitted in the
SGU type AC coaches, each coach has two plants

18. Battery set
• The DC output from the two alternators are
paralleled with the 110V battery set of 800A-hr
capacity which consists of 56 lead acid cells
connected in series, housed in two battery boxes
mounted on under frame of AC coaches of BG
• On the MG AC sleeper the battery consists of 5
cells/3cells mono block construction arranged in 3
boxes in a row
• During stationary or when coach is running at
speed less than MFO, the entire load is met by this
battery set.

19. Contd..
s.no. Type of AC coach No. of sets and Relevant IS
capacity of specificatio
battery n
1 BG AC 2-tier sleeper 1 set of 800Ah IS:6848
2 BG AC chair car 1 set of 800Ah IS:6848
3 BG AC composite 1 set of 800Ah IS:6848
4 BG AC I class 1 set of 525Ah IS:6848
5 MG AC 2-tier 1 set of 450Ah IS:6848
sleeper

20. Pre cooling through external supply
• Charging and pre cooling of coach is done by
external supply, by means of battery charger of
200A rating mounted on the coach under
frame.two numbers of 415V, 3phase AC pre
cooling sockets are provided diagonally on end
walls of each bogie
• Battery charger consists of a transformer and
simple diode bridge rectifier, secondary of
transformer is provided with taps to give 104 to
140V DC

21. Merits of SGU system
• Independent of mode of traction
• Higher flexibility in rake formation
• Each coach is self sufficient in generation
• Depending upon usage ,can be designed for
required capacity

22. Demerits of SGU system
• Poor efficiency-57%
• Higher weight affects the speed potential-not
suited above 110 kmph
• Poor reliability-no standby for battery and
alternator
• Maintenance and monitoring of batteries,
alternator,axle–pulley, belts etc. needed-as
subjected to vibrations continuously
• Fluctuations in illumination and air(of fans)-due to
variation in voltage during generation and non
generation periods

23. Mid on Generation Type
• Supply is obtained at 110V through one
power car in the center having 230 kVA
DG sets
• Used for trains having frequent stops
• These are being progressively replaced by
MEMU and DMU

24. Merits of MOG system
• Most suitable for slow moving passenger
trains on branch line
• Centralized control in all coaches
• Reduced maintenance as AC lights and fans
are used, also because no bulky batteries
• Higher reliability due to cent percent
standby

25. Demerits of MOG system
• Noise and smoke pollution
• Electrical staff required to operate and
maintain the car
• Commercial space equivalent to one power
car reduced

26. Head on Generation System
Under this head on generation scheme
power can be taken either directly from
OHE through a separated pantograph
mounted on power car or through hotel load
winding already provided in some of three
phase electric locomotive e.g. in M/s ABB
make

27. Present status of HOG
• In Europe HOG system is already in use for
supplying hotel load
• In India Saptagiri Express (12 coaches-9 second
class sitting, 1 AC chair car and 2 SLR) of SR
operating 2 pairs of daily services between
electrified Chennai and Tirupati since 1981is a
train set where power supply for lighting load of
35 KW to the rack is derived from AMO converter
of electric locomotive

28. Merits of HOG system
• Centralized power distribution for hotel
load
• Pollution free and cheaper power
• As compared to SG high reliability, reduced
dead weight and maintenance
• Commercial space not wasted
• Improved haulage capacity of long
trains,best suited for LHB type coaches

29. Demerits of HOG system
• Power interruption of short durations
• Require rake integrity like EOG
• Fitness of OHE for multiple raised
pantograph, safe inter distance between
pantograph need to be specified

30. Control panels
• DC control panel
• AC control panel
• Temperature control panel
• Wiring:--By means of multi stranded PVC
insulated copper cables to specification
ICF/Elect./857. Terminal boards are of fire
retardant FRP material

32. Energy conservation
• One unit of energy saved at user
end is more than two units
produced

33. proposed areas of energy
conservation
• Replacement of incandescent lamps by fluorescent
tube lights/CFL and HPMV lamps by HPSV/metal
halide lamps
• Natural light and ventilation should be used up to
maximum extent
• Provision of electronic ballast and fan regulators
• Use of capacitors for power factor correction

34. • Automation of pumps to reduce pumping
hours
• Provision of frictionless foot valves with
pumps
• Checking and control leakage of
compressed air and liquid
• Minimum number of joints bands in
air/water pipe lines

35. • Maintenance of equipments to ensure high
efficiency
• Use of energy efficient air-conditioning
system
• Use of high capacity generator cars for
reduction in HSD oil consumption
• Switching off generator cars at terminal
stations

36. • Increase in use of non conventional sources
of energy
• Use of electronic energy meter
• Train the users for energy conservation
• Train and award staff for energy
conservation measures
• Energy audit through expert agencies

37. Use of flush type lamps
• Improved illumination-lumen level almost
doubled.
• For the same illumination level one 20W
tube is used instead of two 20W tubes.
• Saving in operational cost.

38. Saving in energy by using improved light fittings
Average light points in an AC coach 24
Wattage of double tube light fitting 40
Wattage of single tube light fitting 20
Saving in watt per point 20
Saving per coach(24x20) in watts 480
Average days of working of coach per year 313
Average working hours of light / coach / day 24
Saving per coach per year in kWh units 3600

41. Energy saving by provision of fluorescent tube light
fittings in place of incandescent lamps
Average light points in a non AC coach 21
Wattage of incandescent lamps 40
Wattage of fluorescent tube light 20
Saving in watt per point 20
Saving per coach(24x20) in watts 480
Average days of working of coach per year 313
Average working hours of light / coach / day 14
Saving per coach per year in kWh units 1840
Total saving per year for 3851coaches in 70,85,840
kWh units