SFC - Specific Fuel Consumption
Indicator of Fuel economy
Measured in terms of Tonne KMs
Definition: Amount of fuel consumed per unit of work done.
Measured both for the Engine and the Total formation of the Train.
Lower the SFC, the Better the Fuel Economy.
The unit of SFC for Engine is Grams/bhp hour. Grams represent Quantity of Fuel, whereas bhp hour (brake horsepower) represents work done. .
At present, the SFC of ALCO Engine is 155 Grams and of GM Engine 150 Grams (Approx.)
ALCO stands for American Locomotive Company
GM stands for General Motors
For the locomotive, the SFC of the engine can be calculated by measuring time to calculate the Horse Power output in terms of BHP.Hr for a specific amount of fuel consumption while the engine is put on load during load box test.
This is more accurate in order to calculate engine efficiency, because output of the engine is measured at the crankshaft, neglecting all other losses of the locomotive.
There is a second method of calculating SFC, in which the amount of work done is measured in terms of Tonne Km. This is more practical because here the total losses incurred in the locomotive/ formation of train are taken into consideration for calculating the SFC.
The unit used is in liters/ 1000 GTKM. (GTKM means KM earned with the gross tonnage hauled including the weight of the locomotive).
As train resistance, air resistance and other parasitic loads of locomotive/ train varies at different speed ranges, so SFC of the locomotive is calculated with respect to its service.
Calculated per 1000 GTKMs
SFC = HSD oil in Liters / 1000 GTKMs
HSD Liters represent Quantity of Fuel, whereas 1000 GTKM represent work done.
HSD stands for High-Speed Diesel
GTKMs -Gross Tonne KMs - KMs earned with the Gross Tonnage hauled (incl: of Weight of Locomotive & Rolling Stock )
NTKMs - KMs earned with the Net tonnage hauled (excl: Weight of Locomotive & Rolling Stock)
Indian Railways -SFC (Approx)
SCR - 2017-18- SFC
SFC for Shunting services - not calculated
SEC - Specific Energy Consumption
For Traction - SEC - Specific Energy Consumption = Used KWH / 1000 GTKMs
Amount of Electricity (in KWH - Kilowatt hours) consumed per unit work (1000 GTKMs done
Engine: The amount of electricity (in KWH - Kilowatt-Hour) consumed per unit work done.
Over the last few years, Railways have been able to improve upon Specific Energy Consumption (SEC) by about 19% through various energy conservation initiatives.
For electric locomotives, there are mainly 3 modes of service for which GTKM earning is recorded to calculate SFC.
The figures of SECs (Approx), accordingly are:
SEC-EMU = 40 KWH./ 1000 GTKM
SEC-Pass = 20 KWH./ 1000 GTKM
SEC-Goods = 8 KWH/ 1000 GTKM
The figures represented by electrical department is entirely rhetoric. Because for EMUs for recording energy consumption the energy meter is not available with the locomotive and the figures are purely based on assumption.
For passenger and goods service locomotives, although an energy meter is available figures are manipulated.
For locomotives in shunting service GTKM earning can’t be recorded, hence it is not calculated.
Both SFC and SEC units are used in the Fuel budgeting of Diesel and Traction.
Factors that affect SFC
Other factors P.Way, Signaling, Operating facilities
Steps were taken to bring fuel efficiency
Arresting any leakages.
Application of Fuel Kit
High performance & high capacity turbo supercharger
Improved Air Cooler
Improved Piston and Piston ring
Use of Multigrade oil
Minimum inventory in RCDs - From 15 days to 5 days
Use of B-5 blended HSD - 5 % Bio Diesel
Fuel pattern - Cheaper RCDs are fuelling more to Diesel Locomotives to avoid fuelling at costlier RCDs
Withdrawn overaged WDMs Locomotives from mainline services
DPC - Driving Power Car of DEMU train - Conversion to dual-fuel i.e., Diesel + CNG
Auxiliary Power Unit - introduced in Diesel Locomotives - for automatic shutting down of Diesel Locomotives while standing idle.
CReDI - Common Rail electronic Direct Injection - Developed & Fitted in Diesel Locomotives
Developing alternative fuel systems like Traction, Solar Power to reduce the consumption of Diesel.
IROAF - Indian Railways Organization of Alternate Fuels, Chennai - Developing the alternative fuel.
The performance of Loco Pilots is being monitored regularly.
Monitoring of idling of Locomotives has been started through REMMLOT - Remote Monitoring and Management of Locomotive and Trains fitted in Locomotives.
All overaged Broad Guage Diesel Mixed Traffic Engines (WDM2) locomotives have been withdrawn from mainline service.
Retro-fitment of Microprocessor control system in diesel Locomotives have been executed to achieve fuel efficiency.
Miller cycle-based turbochargers and Variable Turbine Geometry (VTG) Turbochargers have been developed for ALCo locomotives to achieve fuel efficiency.
Indian railways have planned for 1000 MW of solar power plants by 2020-21 with 500 MW at railway rooftops for non-traction use and 500 MW land-based for mostly in traction use.
The solar power from land-based plants shall be mostly used in train operations.
IROAF is implementing the provision of Solar Panels on the rooftop of coaches and Brake Vans of freight trains for taking up part of hotel load (electric lighting and fans load).
In Goods train, Solar Panels on a trial basis have been fitted on the rooftop of 50 Nos. Guard Brake Vans.
In passenger Trains, Solar panels on a trial basis have been fitted on the rooftop of 06 Nos. Trailer Coaches of Diesel Electric Multiple Units (DEMU).