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Evaluating choice of traction option for a sustainable Indian Railways
Transportation Research Part D 33 (2014) 135–145
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Transportation Research Part D journal homepage: www.elsevier.com/locate/trd
Evaluating choice of traction option for a sustainable Indian Railways Mohita Gangwar a,⇑, Sachinder Mohan Sharma b,1 a b
FORE School of Management, B-18, Qutub Institutional Area, New Delhi 110016, India Ministry of Railways, Railway Board, New Delhi 110002, India
a r t i c l e
i n f o
Keywords: Railways Climate change Social Sustainable
a b s t r a c t The transport sector is a major contributor of carbon emissions in India. As railways are the most environment-friendly mode of transport we look at the spearheading role of Indian Railway (IR) in bringing about the modal shift from road and airways to rail with a holistic perspective considering India’s development stage and resource situation. India being an emerging economy, faces many other social and developmental challenges, which have to be incorporated in assessing the viability of the solutions. In order to assess the total impact of the transportation sector a ‘wells to wheels’ approach needs to be adopted to quantify the emissions from the production to distribution and final usages alongside its impact to the competing societal goals utilizing the same resources. This study focuses on evaluating IR’s critical policy decision towards providing efficient transport i.e. the choice of traction. It is inferred that until such time the fuel mix of power production in India remains the same, i.e. coal dominated and there is a shortage of electricity in the country, the accumulated carbon footprints of running electric locos will be higher. There should be a judicious mix of both the tractions to achieve a balance in environmental efficacy, sustainability and equity. Ó 2014 Elsevier Ltd. All rights reserved.
Introduction India is home to about one third of the world’s population and is confronted with various social and economic issues like poverty alleviation, provision of electricity and clean drinking water to the people. To meet the above goals India needs to grow @7–8% for the next two decades and this implies commensurate energy requirements that have to be met in a sustained manner. There is pressure on the scarce financial resources for these competing and often conflicting demands as against the additional expenditure for low carbon strategies. As India is a developing country and the resources are limited the impact of choice of traction also affects the electricity dynamics of the country which is woven to the social and economic development of other sectors. In this paper, the option of choice of traction for IR has been assessed with respect to technical, economic and societal perspectives for India.
⇑ Corresponding author. Tel.: +91 11 41242424. 1
E-mail addresses: [email protected], [email protected] (M. Gangwar), [email protected] (S.M. Sharma). Tel.: +91 9868648788.
http://dx.doi.org/10.1016/j.trd.2014.08.025 1361-9209/Ó 2014 Elsevier Ltd. All rights reserved.
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Global emission scenario In 2009, India signed the Major Economic Forum (MEF) declaration and agreed for voluntary emission cuts and in 2010, an expert group was set up to guide India on a path of a low carbon economy. At the international level, India has been instrumental in development of the climate change norms and rules and in 2010, it accounted for 20% of all the Clean Development Mechanism (CDM) projects registered worldwide under the United Nations Framework Convention on Climate Change (UNFCC). Being an emerging economy and with the increase in its energy requirements its emission of Green House Gases (GHG) are likely to go up in the future. Although the per capita CO2 emissions in India are amongst the lowest in the world, yet during the period 1990–2004 emissions have grown by 97% (Sengupta, 2012, 9). Inspite of all the initiatives India ranks 155 out of 178 countries based on the environmental performance index 2014(EPI). This indicator has various sub indicators like health impacts, air quality, water and sanitation, water resources, agriculture, forest, fisheries, biodiversity and habitat and climate and energy. If we look specifically at the climate and energy indicator which assesses mitigation action and access to energy relative to a country’s level of economic development, India is ranked 104. China which has far higher emission levels and growth rate is ranked 21 and this shows that India needs to do a lot in this direction of cleaner and sustainable development (University, 2014) (see Fig. 1). Transport and climate change Growing usage of transport is causing long term damage to the climate. It is leading to an average increase in the production and consumption of fossil fuels. Oil is the dominant fuel for transportation and road transport consumes 81% of the total energy used in the transport sections (WBSCD, 2001). The transport sector contributes 23% towards global CO2 emissions. Out of this Asia accounted for 19% of the emissions in 2006 and this was expected to increase to 30% by 2030 (Regmi and Hanaoka, 2011). About 76% of the CO2 emissions from a car are caused by fuel usage, 9% from manufacturing and the balance 15% from losses in the fuel supply chain, as has been indicated by Potter (2003). The freight carried by road, which typically account for half of the traffic transported by road, is the largest contributor for environmental pollution and this is followed by use of cars by individuals. The aviation sector is far more polluting as it discharges GHG’s directly into the atmosphere; however, the traffic carried by this sector is limited. These sectors, however, are growing faster than the other modes thereby worsening the situation (Chapman, 2007). In order to assess the total impact of the transportation sector a ‘wells to wheels’ approach has been adopted to quantify the emissions from the production to distribution and final usages (Johansson, 2003; Mizsey and Newson, 2001; Weiss et al., 2000). Indian carbon emissions scenario-sector wise In India, the power sector generates about 38% of the carbon emissions (Fig. 2) as most of the electricity generating plants are coal and gas based. It is expected that the energy mix in the power production will remain the same even in 2020 and
Fig. 1. Comparative Emission Statistics Source: IEA statistics 2013.
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there will be a net shortage of electricity in the country (Parekh, 2011). Fuel usage in transportation including road, aviation, navigation and Railways resulted in about 142 MT of CO2 equivalent emissions accounting to 7% of the total GHG in 2007 (Parekh, 2011, 17). Amongst all modes, roads emitted 87% of the total GHG and Railways only 5%. As compared to 1994 the emissions in the transport sector have grown at a Compounded Annual Growth Rate (CAGR) of 4.5% as against 3.52% across all sectors combined. It is therefore clear that there is a need to reduce the carbon emissions from the transportation sector and it is here that the Railways can play a major role. If we look at the emissions generated by various modes of transport we notice that railways are perhaps the least polluting. In 2007 rail carried 518 MT in freight transport and generated only 3 MT of CO2 road carried 812 MT of traffic and generated 66 MT of CO2, which is about 14 times more. On the passenger side these modes were comparable (see Fig. 3).
Indian transport scenario During 2007–08, the rail and the road transport sector together carry about 87% of the freight traffic and about 90% of the passenger traffic in India. There has been a consistent fall in the share of the rail traffic and it has been estimated that this sub optimal ratio has caused a loss of about 385 Billion rupees to the Indian economy which is about 16% of the total transport cost (Planning commission of India 2014). The major challenges faced by the transport sector include heavy congestion on roads and their poor quality, poor road infrastructure in rural areas, financial constraints faced by railways, urbanization and road congestion in metros and poor and inefficient port and airport infrastructure (Bank n.d.). India has a road network spanning 41.09 million km which is perhaps the largest in the world. This has increased tenfold since independence. In terms of quality this ranks 85th in the world as only about half the roads are paved. The national highways constitute only 1.7% of the network but carry 40% of the total road traffic. Only 24% of the highways have four lanes and meet international standards The most suitable mode of transport in terms of environmental impact is the waterways but in India the total navigable length of the inland waterways is about 14,500 km. They geographically do not cover all the states and are concentrated only in the states of West Bengal, Goa and Kerala. It is estimated that about 0.1% of the freight cargo in NTKM (Net Tonne Kilo Meters) is carried using the waterways possibly due to the reason that only about 9200 km is fit for use by mechanized crafts (Ministry of Shipping, n.d.). The passenger traffic by air was about 162 million passengers in 2011–12 and the total freight carried has increased at a CAGR of 9.2% in the last 11 years and was about 2.28 million tonnes in 2012.The air traffic density which is defined as 1000 passengers per million urban population in India is about 72 as compared to 2896 in the USA. India has one aircraft per 2.89 million population and this mode of transport is not sustainable for domestic movement (Planning commission of India 2014). To understand the current share of modal traffic we can look at the historical perspective of the transportation sector in India. It is evident from the following table that the market share of rail freight transport has been reducing from 89% in 1950–51 to 30.8% in 2007–08.The majority of this traffic has shifted to the roadways. About 88% of the traffic carried by the Railways consists of bulk commodities like coal, iron ore, cement, food grain, fertilizer, POL, etc. (Banerjee, 2009, 63). Transport being a derived demand and is linked to the growth of the economy or GDP. Based on an elasticity factor of 1.25 for railways growth potential as compared to the country’s GDP, IR has achieved only 0.79 between 1970–71 and 2008–09 (Banerjee, 2009, 5). This perhaps explains the real modal shift towards roadways in India. It may be inferred from an emissions perspective that there is a need for bringing about a modal shift from road to rail. The shift to road is attributable to the fact that the railways were not able to build the infrastructure and provide the service. At the same time there was a substantial growth in the road sector which provided a viable means of transport.
Fig. 2. Source: Parekh (2011).
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Fig. 3. Source: Parekh (2011).
Even in a rail freight or passenger journey the end mile is to be undertaken by road and this is a cause of concern for the customer. The solution to these challenges lie bringing about policy interventions to facilitate a modal shift towards railway systems. An oft adopted policy intervention technique is to administer indirect taxation to make car ownership costly, charge congestion taxes, etc. These schemes are, however, unpopular amongst the masses and may face societal and political resistance. Other intervention schemes like increased dematerialization (reduction of material resources needed per unit of GDP) by carrying out life cycle costing and extended manufacturer’s responsibilities may face implementation issues and might not be very successful. Other innovative strategies to make road vehicles less polluting include improvement in vehicle design and use of non fossil fuels and hybrid car.
Indian Railways status Indian Railway is the largest railway network under a single management in the world. It reaches the underserved and remote areas of India and brings them into the national mainstream of development. Each day its 1.4 million strong work force runs 19,000 trains which carry nearly 20 million passengers and 2.5 million tonne of freight goods making it the lifeline of India. This is about 30% of the freight traffic and 19% of passenger traffic of the country and IR depends heavily on energy obtained by burning of fossils fuels (see Fig. 4). The trains either are run by burning diesel or by electricity produced in coal
Fig. 4. Source: Banerjee, White Paper on Indian Railways (2009).
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Fig. 5. Source UIC (2005).
based thermal power plants. The more we burn fossil fuels for production of energy, the more we pump green house gasses mainly carbon dioxide, methane and nitrous oxide into the atmosphere. The Vision 2020 document is perhaps the first attempt by IR in recognizing carbon mitigation as a corporate objective. It intends to achieve this by critically reviewing the carbon footprints of its projects and striving for energy efficiency in its operations (Banerjee, Vision 2020, 2009). Efforts need to be made to increase the share of rail transport viz-a-viz roads. The choice of traction for railroads is a critical policy decision. Globally, countries have evolved their own strategies either to run diesel locomotive hauled trains, or to run electric locomotive hauled trains that draw power from the overhead traction wires. While on one hand, countries like US and Canada have been predominantly retained diesel traction on its major routes; European countries like Switzerland, France, Germany, etc. that have surplus electricity, are importers of oil and have smaller networks have been on the forefront of electrification of their rail routes. Although for UK, as per their policy statement the case of network wide electrification has been kept in abeyance because the case depends on the decline of carbon foot printing of electric generation and low carbon, self powered trains, neither of which can be forecasted at present (Hope, 2010). The graph below shows the percentage of network electrified in various European countries (see Fig. 5). Transport is a challenging sector and does not respect administrative boundaries and therefore decisions are contested across administrative frontiers (Marsden and Rye, 2010). Continuing fiscal and resource pressures, new rail technologies, and environmental consciousness are forcing the railways to reconsider the policies. However, major investments should be made after a clear and accurate portrayal of the full costs of each mode because it has long term implications. Full costs also include the social costs and environment cost. Although it is universally accepted that electric traction is more appropriate for climate change consciousness its implications in Indian conditions are little understood. As mentioned by Baker et al. the earlier climate change models do not sufficiently capture how transport is embedded in people’s social and economic relationships and how they are likely to shift with changing transport provision (Baker et al., 2010). Our research tries to address these aspects in the Indian Railway scenario. Technical considerations for choice of traction IR today has a fleet of about 9000 locomotives, with approximately 4500 each of diesel and electric type, for running its mainline services on the broad gauge network. The fuel bill for IR is about Rupees157K million with 100K million being spent for diesel and the balance for electric energy (I. Railways, ASS 2011–12, 2012).Presently 35% of the freight and 51% of the passenger traffic is hauled by diesel locos and the rest by electric locos (Railways, Year Book 2011–12, 2012). Before we evaluate the option of traction for IR from an economic perspective, we can compare the relative merits and de merits of both the
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electric and diesel locos from a technical perspective on the following technical parameters: technology, efficiency, operational flexibility, pollution, maintenance and line capacity. Technology Electric locos are lighter and have fewer moving parts as compared to diesels and are therefore easier to maintain. The lightness makes them more track friendly but the additional weight gives the diesel locos higher tractive effort or the ability to start heavier trains. The modern diesels of IR have switched over faster to the highly efficient AC–AC transmission and IGBT (integrated gate bipolar transistor) based technology. These modern diesels more than match the electrics in speed and haulage. In fact, the WDG4 diesel loco with 4500 hp is the only loco on IR, which can start a 5300 T trainload on a gradient of 1:150. Recently a 5500 hp diesel locomotive has also been developed with higher speed potential. Similarly the electric locos have been modified for higher adhesion and thus a higher starting load capability. For the same weight, the diesels can haul 10% higher loads. In terms of speed the electric WAP7 with 6000 hp and with a speed potential of 200 kmph is superior for passenger operations (R. I. Railways, 2001). Efficiency Diesels burn the fuel to produce energy, which is then transformed into electric energy for traction purposes. The efficiency of modern diesels used by IR is about 35%. The Loco to Grid efficiency of an electric loco is 98%. However, as per the ‘Well to Wheel’ approach we need to consider the total efficiency of the electric engine from the power plant to the wheels to compare the two on a level platform. Most of the power plants in India are coal fired and operate at efficiencies of about 30–35%. By the time this electricity reaches the locomotive there are further 10% of transmission losses and 2% losses in the locomotive. Thus, the total efficiency is in the range of 28–30% for electric traction. It can be inferred that on a wells to wheel approach the diesels are marginally more efficient in terms of energy use. Operational flexibility The major advantage of diesel locos is that they can work seamlessly under all conditions and all terrains whereas the electrics can only run in the electrified sections. The requirement of changing locomotives causes delays to trains. The capital cost of laying the OHE is substantial, every 10 km of wired route is equal to the cost of an electric loco. Apart from this any disruption in the grid supply affects the train operation instantaneously. In addition, the capacity of the OHE limits the number of trains that can work in a section due to network effects. The wires are also exposed to adverse weather conditions and require additional maintenance during snowfall; rains etc. spoil the appearance of the surroundings and are prone to theft. The height of these wires also places restrictions on the Maximum Moving Dimensions (MMD) on the rail network and inhibits the increase in height of the freight and passenger cars, leading to loss in carrying capacity for the same length of train. An operational limitation is moving trains where the wired territory ends as matching diesel locomotives have to be provided and this leads to sub-optimal utilization of locomotives. Also there is a need for providing power blocks for the maintenance of the over head equipment and this may reduce the line capacity of the section and any blockage in a section directly affects the throughput if the section is heavily used. The main limitation of a diesel engine is that they have to be fuelled at regular intervals in contrast to electric locos, which can work without any refueling delays. Elaborate arrangements have to be made for moving and storing the fuel for diesel locos. The electrics on the other hand have independence from any such infrastructure. If we compare in terms of sources of power, they can run on electricity produced from any source like coal, gas, diesel, renewable etc. and this is extremely useful for energy security as we move towards renewable energy sources for electricity generation. Diesels are wedded to diesel fuel, however in recent times bio diesel from various sources is also used to blend with the diesel. Pollution The diesel loco, which is a primary producer of electricity, generates black smoke and higher noise as compared to an electric loco (see Fig. 6). On the other hand, the visible pollution from an electric loco is missing. However, the pollution occurs at the electricity generation site i.e. the source – the electricity power plant. The Research wing of IR has carried out a study comparing the pollution from diesel loco and thermal power plants as most of the energy for electric traction in India is obtained from them. The study highlights that the major pollutants from diesel locomotives include only NOx and particulate emissions whereas the major pollutants from thermal power plants include suspended particulate matter (SPM), oxides of nitrogen (NOx), sulfur dioxide (SO2) and ash (Kathpal, 2006). The modern Diesel locos complying to US Environmental Protection Agency (EPA) Tier1 norms are 12% better in particulate emissions and 77% in SO2 emissions (RDSO Railways, 1996). However, the electric traction is more useful for operation in tunnels and underground areas usually for suburban traffic where pollution poses major challenge. The diesel locos also consume about 11 times more lubricating oil than the electrics which is a source of pollution and higher maintenance costs (I. Railways, ASS 2011–12, 2012).
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Fig. 6. Source: www.irfca.org (n.d.).
Maintenance (electric v/s diesel loco) The electric locos have longer schedule periodicity and touch the base shed after 90 days. However, separate trip sheds are required for attention after every trip. Normally diesel locos touch the base shed after 60 days but do not require any attention in between. The modern diesels being produced by IR require touching the home shed after 90 days and are comparable to the electrics. Manpower ratio(number of maintenance staff per loco) for diesel locos is about 5.75 as compared to 4.31 for the electric locos (I. Railways, Indian Railways, 2012). The modern diesel locomotives work with an availability of 91% as compared to the conventional diesels and electric locos which have a target based on 81% availability. Constraint of line capacity If we analyze the Line capacity utilization, which is the ability of the same network to handle more trains or throughput, theoretically, it is expected that line capacity shall improve with electrification of the section. Factually, if we look at the running time of trains after electrification it is evident that the speeds have not gone up and trains are detained for new reasons like traction change i.e. change from diesel to electric locos and vice versa. Line capacity can only increase with seamless movement of trains by using diesel locos or further electrifying the adjoining routes till the originating/terminating stations. In many cases it becomes essential to run diesel under wire for operational flexibility and so the full benefit of electrifying a section is not reaped. Total electrification is not a feasible option because it will expose IR to more risk and make it more vulnerable to traffic disruption. In many cases, the capacity decreases because of additional maintenance blocks requirement during which period the movement of trains is restricted. So, IR has not been able to realize the actual benefit of throughput increase. A viable method of improving the line capacity is by reducing the differential in speeds of passenger and freight trains as these use the same tracks for their operation. The passenger trains on IR move at average speeds of about 55 kmph whereas the speed of freight trains is about 25 kmph. This speed differential on the same track results in loss of line capacity as freight trains have to make way for the time tabled passenger trains. This can be mitigated by right powering of the freight trains by providing higher horsepower locomotives or by double heading the locomotives (use of two locomotives in a multiple unit formation). Another option is to run the passenger trains in shadow blocks i.e. one after the other so that there is no speed differential between subsequent trains. This is however not practical as the punctuality of passenger trains is about 84% and the schedule of the passenger trains have to be devised keeping the needs and preferences of the passengers. The above argument shows that both the diesel and electric locos are technically comparable in their performance and so the decision on the choice of traction is not clear-cut. Economic assessment of choice of traction The operational cost of diesel and electric traction is based on statistics published by the Railways. GTKM (Gross Train Kilo Meters) is the gross load of the train including the weight of the locomotive in tones multiplied by the distance in kilometers. SFC (Specific Fuel Consumption) for diesel locos and is measured in liters of diesel consumed divided by the GTKM in thousands. Similarly the SEC is the Specific Energy Consumption for electric locos and is measured by dividing the electric energy consumed by the GTKM in thousands. Whereas the calculation for diesels is based on actual, the calculation for electrics is an empirical approximation as the energy consumed is common for passenger and freight service and has to be apportioned accordingly. The calculations of traction costs include the fuel, lubricating oil, maintenance of locomotives and maintenance of the Over Head Equipment costs. On the basis of the calculations based on the published
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figures of the Annual statistical Statement of 2010–11, it is evident that electric traction is cheaper in fuel costs by Rs. 0.1 million for every 2 million GTKM’s of traffic hauled equally divided between passenger and freight. Similarly, it is marginally cheaper in lubricating oil consumption but it is costly to operate electric locos and maintain the OHE. However, based on the total GTKM’s of the section as well as its length a complete analysis is conducted. Since fuel, costs are most important their fluctuation has a severe impact on the Rate of Return over 30-year life cycle of the electrification proposal. So on purely financial considerations it may be prudent to run trains on electric traction in case the level of traffic exceeds a minimum threshold level that offsets the initial capital expenditure in electrification of the tracks. Societal considerations for assessment of the choice of traction As mentioned in the studies on the Global Sustainability scenario the social values are centered on a community with strong emphasis of enhancing social equity and protecting the environment (Jaroszweski et al., 2010). Therefore, the climate change initiatives have to be evaluated with respect to their impact on the society. In our analysis we consider the societal considerations in addition to the economic, technological and ecological perspective (Neil Adger et al., 2009). We have adopted a scenario-based approach. The IPCC (2001) describes the scenario as: ‘‘A plausible and often simplified description of how the future may develop, based on a coherent and internally consistent set of assumptions about key driving forces (e.g. rate of technology change, prices) and relationships (Working Group, 2001).’’
If we look at India’s power scenario, in 2011–12 India’s generating capacity was 788 BkWh yet about 300 million citizens did not have electricity. This comprised about 6% of urban population and the balance is rural. The Central electricity authority (CEA) of India has estimated that the base load shortage is about 10.3% and peak load about 12.3% for the year 2011–12. Apart from this India has perhaps the highest T&D loss in the world amounting to about 24% (Power, 2012). If we assume that the economy will grow at 8% and all efforts are made to achieve energy efficiency, the demand in 2020 will be about 1715 BkWh. To make good this shortfall India will need to add capacity @20,000 kWh per year however in the recent years the increase has been about 10,000 kWh per year. It is therefore likely that this shortage will continue in the future and the current fuel mix with coal as the dominant fuel, for producing this electricity will remain (Parekh, 2011). As per estimates IR consumes only about 2% of this electricity for Traction purpose (Committee, 2012). It receives an uninterrupted supply and pays for what it receives i.e. the T&D losses are borne by the utilities. It can be inferred that in case IR did not use electric traction this would have resulted in lesser shortage and electricity available to the industry and agriculture. Industry and agriculture on the other hand for their consumption are using less efficient diesel engines to generate electricity. So this argument can be understood in terms of rail electrification contributing to dieselization of the industry, agriculture and domestic sector where inefficient diesel generator sets are providing the electricity at double the cost and increased pollution. Thus, in electricity constrained scenario in India, electrification of IR will lead to dieselization of other sectors. If we look at the oil situation in India, about 70% of the fuel requirement in India is met through imports. Domestic Diesel Consumption has been enjoying a subsidy by the government. However, in January 2013 the subsidy on diesel for the bulk consumers like Indian Railways has been withdrawn which has made diesel expensive by about 20%. Fuel costs contribute towards 18% of the revenue expenditure of Indian railways and this increase has shifted the economics of traction in favor of electrification. However, as mentioned earlier the forced dieselization of agriculture and domestic sector translates into increased flow of subsidies from the Government to the agricultural and industrial sector at the cost of Indian Railways. In addition, if we look at the transport sector in India, the share of rail transport has reduced whereas the transport sector per se has increased thereby increasing diesel consumption at lower subsidized rates. Carrying the argument further to the concept of equity, it translates into contributing to non-availability of basic electricity to rural India at the cost of rail travel. In view of this, the electrification of railway should be coordinated and linked to the electrification of the country and a careful prioritization of sectors for electricity distribution in case of a capacity constrained electricity generation has to be undertaken. The resilience of the network in case of an accident is an important factor to be considered in this evaluation. This can be interpreted as the time taken to restore the operations after disruption. In an electrified section, the restoration after an accident takes a longer time as the catenaries’ (over head wires which carry the electric power) have to be slewed to make place for the breakdown cranes to function. This takes an additional 45 min before and after the restoration and requires extra work force and coordination to do this task. In case of damage to the over-head equipment or the masts, the time and costs can be higher. As far as the passengers are concerned, it means higher time delay costs and decrease in the throughput as all the traffic is blocked on the route. An important element for sustainable development scenario is the need to manage effectively long term threats to security of energy supply by reducing the exposure to the risk of supply disruptions by a combination of diversification and demand reduction (Turton, 2006). In the present case when there is a grid failure it brings the operation to a halt. This total dependence on electrification can expose the railway to sabotage as well. Thus, an electrified network is less resilient and
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Fig. 7. Scenario analysis for IR Electrification decision.
Fig. 8. Ref: Limited (2007).
vulnerable. The network becomes more resilient if certain numbers of diesel locomotives are run by diversifying the traction portfolio (see Fig. 7). The business as usual with a judicious mix of diesel and electric traction can help solve the anomalies. The proposed systems consists of running a few scheduled passenger trains on diesel and also freight trains above a certain threshold limit on diesel even after electrification of the section. There is high volatility in energy consumption for electrified sector. Railways traction electric energy charges are calculated in three parts. Railways ascertain a maximum contract demand in kilo Volt Amperes for each substation based and pay a minimum guaranteed amount for the maximum demand (MD) in Rupees per KVA. There is a penalty if the demand goes over and so railways take a liberal view while ascertaining the requirement. The graph below shows the fluctuation in the demanded quantity over a three year period for a typical substation. Similar fluctuations are noted in a 24 h cycle daily as the trains run vary from day to day. Apart from this an energy usage charge per unit is paid for the actual energy consumed. There is a penalty if power factor falls below a specified value. Billing Demand is therefore a certain percentage of contract demand or the actual MD whichever is higher. Excess over Contract Demand and corresponding units of energy is usually charged at higher tariff (see Fig. 8). The combination of diesel and electric traction can be used in such a way that the volatility of electric traction consumption is reduced. The peaks in the requirements can be pruned down close to the average daily demand by running a few diesel trains at those particular times to reduce the electrical load, thereby lowering the maximum contracted demand of electricity. Another advantage would be that in case of power disruption the availability of diesel locomotives in the section will help in early restoration of operations, thus making it more resilient (see Fig. 8). Indian railways action towards reducing carbon footprints As part of its Vision 2020, IR is committed to take up its mission of setting challenging targets for carbon productivity and to devise a road map to achieve the same in a cost effective manner. It intends to make its operations environment enhancing by over compensating the environmental damage caused by its transport activities by adopting green technologies. IR has already taken up manufacture of efficient locomotives, lighter coaches and wagons, energy audits, use of regenerative braking in suburban trains, setting up of windmill and biodiesel plants, adopting CNG for transport and stationary applications etc. IR is also using its influence to make its vendors, partners and its own units more eco friendly and climate compliant with exacting standards (Banerjee, Vision 2020, 2009). In order to have a modal shift IR has to overcome the bottlenecks in its infrastructure on these routes so as to improve their line capacity or develop alternate routes to serve the traffic needs. Indian Railways carries 55% of the freight traffic and 60% of the passenger traffic on the golden quadrilateral linking the cities of Delhi, Mumbai, Chennai and Kolkata (CRIS n.d.).
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This also implies that rest of the route has spare capacity and there is a need to find traffic to run on these sections. Some of the options available are doubling or quadrupling the lines, making new lines, increasing the carrying capacity of wagons and coaches, running longer trains, upgrading the signaling and track, electrification of the routes etc. Apart from generating capacity these efforts will smoothen the operations which will result in fuel efficiency for IR and resultant reduction in carbon emissions. Two major initiatives under process are the setting up of the Dedicated Freight Corridor’s (DFC) and registering of a few doubling projects under the CDM scheme. It has been estimated that the Western DFC alone would reduce CO2 emissions by 81%. The net reductions are expected to be 68.61 MT of CO2 in the year 2046 (Pangotra and Shukla, 2012). Not only this IR has set specific targets for fuel efficiency, use of non conventional energy sources, improved utilization of rolling stock, execution of doubling and other projects and manufacture of new design rolling stock in its Results framework document (RFD) which is monitored by the Planning Commission. IR seems to be on the right path to address the concern of end use efficiency (Placeholder1). Conclusion India has shown its commitment to reducing carbon emission intensity of its economy and has promised the International community that it will undertake measures in this direction. India’s logistics infrastructure is ill equipped, insufficient and ill designed to support the expected 7–8% growth till 2020. India has an opportunity to address this as most of the infrastructure network is yet to be built. Learning from the past and adopting best practices India should build its infrastructure in a manner that integrates the various modes at the same time prioritizing higher return projects in the efficient modes. Presently, Transport development is being done in silos and there are always last mile connectivity issues. All the stakeholders which includes policy makers, regulators, service providers, resource holders, end users, etc. should plan and act together to achieve this. As far as IR is concerned it needs to realize its potential as the most efficient mode of transport in India in terms of fuel, land usage and carbon footprints and it has to petition for greater financial support from the Government. This is essential otherwise; its share in the transport sector will come down even further. The funds it receives have to be gainfully utilized for its projects that improve line capacity. Although cost plays a little role in the choice of modes there is a need to bring about policy interventions to internalize the external costs of each mode to bear the social costs so that a socially optimal modal shift can be achieved. Even within a mode there is a need to separately cost the freight and passenger business. This would ensure that there is no cross subsidization of the passenger transport by the railways by using the profits generated from the freight business. Through these sustained efforts only will IR be able to gain share of traffic from other modes. The evidence from the study suggests that the diesel and electric locos plying on IR have their relative merits and demerits but are comparable in their performance. With the current trend and sanction of Electrification, IR will electrify about 60% of its network in the next 6–8 years. Although the operational cost of electric locos is lesser but the initial capital, required for electrifying the network is high. With all the major routes already electrified, the benefit of such operational savings is reducing as new sections that are being considered for electrification have less traffic density. Till the fuel mix of power production remains the same i.e. coal dominated and there is a shortage of electricity in the country, the carbon footprints of running electric locos will be higher. The opportunity costs of the investment in electrification are also high. It is concluded that IR should not further proliferate Electrification of its routes but should strengthen the infrastructure on the existing routes by doubling them etc. There should be a judicious mix of both the tractions to achieve operational flexibility and efficiency. IR should continue to endeavor to improve the energy efficiency of its locomotives during driving, minimizing fuel consumption, optimizing load factor, and improving design of coaches and wagons to reduce the operational costs and carbon footprints. Considering a macro view, also it is important for the Government to have an integrated transport development plan and to come up with policies and incentives for bringing about a modal shift towards Railways Transport strategy must cut across modes of transport, administrative and geographical boundaries and should integrate capital investment with regulatory and policy development. Although strategy should be made for the long term it should be dynamic and flexible enough to respond to the ongoing changes like the advent of alternate fuels etc which would alter the efficacy of the transportation alternative (Planning Commission, 2014). As per the IPCC assessment reports the global temperature rise is imminent and it is imperative that the transport policies also look at adaptation strategies. This is of prime importance as most of the Asian countries are in the process of expanding their transport infrastructure. Transport infrastructure including that of railways is adversely affected by extreme weather like flooding, storms etc. It is easier to introduce these adaptive measures at an early stage by carrying out a risk/ vulnerability analysis and environment impact assessment (Regmi and Hanaoka, 2011) as spatial plans are difficult to revise and there are many players involved in their development. References Baker, C.J., Chapman, L., Quinn, A., Dobney, K., 2010. Climate change and the railway industry: a review. J. Mech. Eng. Sci. 224 (3), 519–528. Banerjee, Mamta, 2009. Vision 2020. Ministry of Railways, New Delhi. Banerjee, Mamta, 2009. White Paper on Indian Railways. Ministry of Railways, New Delhi. Chapman, Lee, 2007. Transport and climate change: a review. J. Transport Geogr., 354–367. Committee, 2012. Indian member. India energy book. (accessed 11.11.2012).
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CRIS, 2012. (accessed 03.05.2014). Marsden, Greg, Rye, Tom, 2010. Governance of transport and climate change. J. Transport Geogr., 669–678. Ministry of Shipping, Government of India, 2014. Inland waterways authority of India. (accessed11.11.2012). Railways, Indian, 2012. Indian. Annual Statistical Statement 2010–11. Statistical. Ministry of Railways, New Delhi. Indian Railways. June 2012. (accessed 11.11. 2012). Railways, Indian. 2012. . (accessed 11.10.2012). Railways, Indian, 2012. Year Book 2011-12. Statistical. Ministry of Railways, New Delhi. Railways, RDSO Indian, 2001. Diagram Book of WDG4. Miscellaneous. MP Dte. RDSO, Lucknow. RSDO Railways, Indian, 1996. Emission on Fuel Efficient DLW 6 Cylinder 251D Engine. Technical. Ministry of Railways, Lucknow. Regmi, Madan B., Hanaoka, Shinya, 2011. A survey on impacts of climate change on road transport infrastructure and adaptation strategies. Environ. Econ. Policy Stud. 13 (1), 21–41. Sengupta, S., 2012. International Climate negotiations and India’s role9. Turton, H., 2006. Sustainable Global automobile Transport in the 21st Century: an integrated scenario analysis. Technol. Forecasting Soc. Change 73, 607– 629. UIC, 2012. . (accessed 11.20.2012). University, Yale. Environmental performance Index. 2014. (accessed 02.3.2014). WBSCD. Mobility 2001: World Mobility at the end of the twentieth century and its Sustainability. WBSCD. 2001. (accessed 10.22.2013). Weiss, M.A., Heywood, K.J.B., Drake, E.M., AuYeung, F.F., 2000. On the Road in 2020—A Life Cycle Analysis of New AutomobileTechnologies. Energy Laboratory, MIT. Working Group, 2. IPCC 2001 Impacts, Adaptation and Vulnerability, Cambridge University Press, 2001, p. 251. www.irfca.org. (accessed 11.12.2012).
Contents lists available at ScienceDirect
Transportation Research Part D journal homepage: www.elsevier.com/locate/trd
Evaluating choice of traction option for a sustainable Indian Railways Mohita Gangwar a,⇑, Sachinder Mohan Sharma b,1 a b
FORE School of Management, B-18, Qutub Institutional Area, New Delhi 110016, India Ministry of Railways, Railway Board, New Delhi 110002, India
a r t i c l e
i n f o
Keywords: Railways Climate change Social Sustainable
a b s t r a c t The transport sector is a major contributor of carbon emissions in India. As railways are the most environment-friendly mode of transport we look at the spearheading role of Indian Railway (IR) in bringing about the modal shift from road and airways to rail with a holistic perspective considering India’s development stage and resource situation. India being an emerging economy, faces many other social and developmental challenges, which have to be incorporated in assessing the viability of the solutions. In order to assess the total impact of the transportation sector a ‘wells to wheels’ approach needs to be adopted to quantify the emissions from the production to distribution and final usages alongside its impact to the competing societal goals utilizing the same resources. This study focuses on evaluating IR’s critical policy decision towards providing efficient transport i.e. the choice of traction. It is inferred that until such time the fuel mix of power production in India remains the same, i.e. coal dominated and there is a shortage of electricity in the country, the accumulated carbon footprints of running electric locos will be higher. There should be a judicious mix of both the tractions to achieve a balance in environmental efficacy, sustainability and equity. Ó 2014 Elsevier Ltd. All rights reserved.
Introduction India is home to about one third of the world’s population and is confronted with various social and economic issues like poverty alleviation, provision of electricity and clean drinking water to the people. To meet the above goals India needs to grow @7–8% for the next two decades and this implies commensurate energy requirements that have to be met in a sustained manner. There is pressure on the scarce financial resources for these competing and often conflicting demands as against the additional expenditure for low carbon strategies. As India is a developing country and the resources are limited the impact of choice of traction also affects the electricity dynamics of the country which is woven to the social and economic development of other sectors. In this paper, the option of choice of traction for IR has been assessed with respect to technical, economic and societal perspectives for India.
⇑ Corresponding author. Tel.: +91 11 41242424. 1
E-mail addresses: [email protected], [email protected] (M. Gangwar), [email protected] (S.M. Sharma). Tel.: +91 9868648788.
http://dx.doi.org/10.1016/j.trd.2014.08.025 1361-9209/Ó 2014 Elsevier Ltd. All rights reserved.
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Global emission scenario In 2009, India signed the Major Economic Forum (MEF) declaration and agreed for voluntary emission cuts and in 2010, an expert group was set up to guide India on a path of a low carbon economy. At the international level, India has been instrumental in development of the climate change norms and rules and in 2010, it accounted for 20% of all the Clean Development Mechanism (CDM) projects registered worldwide under the United Nations Framework Convention on Climate Change (UNFCC). Being an emerging economy and with the increase in its energy requirements its emission of Green House Gases (GHG) are likely to go up in the future. Although the per capita CO2 emissions in India are amongst the lowest in the world, yet during the period 1990–2004 emissions have grown by 97% (Sengupta, 2012, 9). Inspite of all the initiatives India ranks 155 out of 178 countries based on the environmental performance index 2014(EPI). This indicator has various sub indicators like health impacts, air quality, water and sanitation, water resources, agriculture, forest, fisheries, biodiversity and habitat and climate and energy. If we look specifically at the climate and energy indicator which assesses mitigation action and access to energy relative to a country’s level of economic development, India is ranked 104. China which has far higher emission levels and growth rate is ranked 21 and this shows that India needs to do a lot in this direction of cleaner and sustainable development (University, 2014) (see Fig. 1). Transport and climate change Growing usage of transport is causing long term damage to the climate. It is leading to an average increase in the production and consumption of fossil fuels. Oil is the dominant fuel for transportation and road transport consumes 81% of the total energy used in the transport sections (WBSCD, 2001). The transport sector contributes 23% towards global CO2 emissions. Out of this Asia accounted for 19% of the emissions in 2006 and this was expected to increase to 30% by 2030 (Regmi and Hanaoka, 2011). About 76% of the CO2 emissions from a car are caused by fuel usage, 9% from manufacturing and the balance 15% from losses in the fuel supply chain, as has been indicated by Potter (2003). The freight carried by road, which typically account for half of the traffic transported by road, is the largest contributor for environmental pollution and this is followed by use of cars by individuals. The aviation sector is far more polluting as it discharges GHG’s directly into the atmosphere; however, the traffic carried by this sector is limited. These sectors, however, are growing faster than the other modes thereby worsening the situation (Chapman, 2007). In order to assess the total impact of the transportation sector a ‘wells to wheels’ approach has been adopted to quantify the emissions from the production to distribution and final usages (Johansson, 2003; Mizsey and Newson, 2001; Weiss et al., 2000). Indian carbon emissions scenario-sector wise In India, the power sector generates about 38% of the carbon emissions (Fig. 2) as most of the electricity generating plants are coal and gas based. It is expected that the energy mix in the power production will remain the same even in 2020 and
Fig. 1. Comparative Emission Statistics Source: IEA statistics 2013.
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there will be a net shortage of electricity in the country (Parekh, 2011). Fuel usage in transportation including road, aviation, navigation and Railways resulted in about 142 MT of CO2 equivalent emissions accounting to 7% of the total GHG in 2007 (Parekh, 2011, 17). Amongst all modes, roads emitted 87% of the total GHG and Railways only 5%. As compared to 1994 the emissions in the transport sector have grown at a Compounded Annual Growth Rate (CAGR) of 4.5% as against 3.52% across all sectors combined. It is therefore clear that there is a need to reduce the carbon emissions from the transportation sector and it is here that the Railways can play a major role. If we look at the emissions generated by various modes of transport we notice that railways are perhaps the least polluting. In 2007 rail carried 518 MT in freight transport and generated only 3 MT of CO2 road carried 812 MT of traffic and generated 66 MT of CO2, which is about 14 times more. On the passenger side these modes were comparable (see Fig. 3).
Indian transport scenario During 2007–08, the rail and the road transport sector together carry about 87% of the freight traffic and about 90% of the passenger traffic in India. There has been a consistent fall in the share of the rail traffic and it has been estimated that this sub optimal ratio has caused a loss of about 385 Billion rupees to the Indian economy which is about 16% of the total transport cost (Planning commission of India 2014). The major challenges faced by the transport sector include heavy congestion on roads and their poor quality, poor road infrastructure in rural areas, financial constraints faced by railways, urbanization and road congestion in metros and poor and inefficient port and airport infrastructure (Bank n.d.). India has a road network spanning 41.09 million km which is perhaps the largest in the world. This has increased tenfold since independence. In terms of quality this ranks 85th in the world as only about half the roads are paved. The national highways constitute only 1.7% of the network but carry 40% of the total road traffic. Only 24% of the highways have four lanes and meet international standards The most suitable mode of transport in terms of environmental impact is the waterways but in India the total navigable length of the inland waterways is about 14,500 km. They geographically do not cover all the states and are concentrated only in the states of West Bengal, Goa and Kerala. It is estimated that about 0.1% of the freight cargo in NTKM (Net Tonne Kilo Meters) is carried using the waterways possibly due to the reason that only about 9200 km is fit for use by mechanized crafts (Ministry of Shipping, n.d.). The passenger traffic by air was about 162 million passengers in 2011–12 and the total freight carried has increased at a CAGR of 9.2% in the last 11 years and was about 2.28 million tonnes in 2012.The air traffic density which is defined as 1000 passengers per million urban population in India is about 72 as compared to 2896 in the USA. India has one aircraft per 2.89 million population and this mode of transport is not sustainable for domestic movement (Planning commission of India 2014). To understand the current share of modal traffic we can look at the historical perspective of the transportation sector in India. It is evident from the following table that the market share of rail freight transport has been reducing from 89% in 1950–51 to 30.8% in 2007–08.The majority of this traffic has shifted to the roadways. About 88% of the traffic carried by the Railways consists of bulk commodities like coal, iron ore, cement, food grain, fertilizer, POL, etc. (Banerjee, 2009, 63). Transport being a derived demand and is linked to the growth of the economy or GDP. Based on an elasticity factor of 1.25 for railways growth potential as compared to the country’s GDP, IR has achieved only 0.79 between 1970–71 and 2008–09 (Banerjee, 2009, 5). This perhaps explains the real modal shift towards roadways in India. It may be inferred from an emissions perspective that there is a need for bringing about a modal shift from road to rail. The shift to road is attributable to the fact that the railways were not able to build the infrastructure and provide the service. At the same time there was a substantial growth in the road sector which provided a viable means of transport.
Fig. 2. Source: Parekh (2011).
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Fig. 3. Source: Parekh (2011).
Even in a rail freight or passenger journey the end mile is to be undertaken by road and this is a cause of concern for the customer. The solution to these challenges lie bringing about policy interventions to facilitate a modal shift towards railway systems. An oft adopted policy intervention technique is to administer indirect taxation to make car ownership costly, charge congestion taxes, etc. These schemes are, however, unpopular amongst the masses and may face societal and political resistance. Other intervention schemes like increased dematerialization (reduction of material resources needed per unit of GDP) by carrying out life cycle costing and extended manufacturer’s responsibilities may face implementation issues and might not be very successful. Other innovative strategies to make road vehicles less polluting include improvement in vehicle design and use of non fossil fuels and hybrid car.
Indian Railways status Indian Railway is the largest railway network under a single management in the world. It reaches the underserved and remote areas of India and brings them into the national mainstream of development. Each day its 1.4 million strong work force runs 19,000 trains which carry nearly 20 million passengers and 2.5 million tonne of freight goods making it the lifeline of India. This is about 30% of the freight traffic and 19% of passenger traffic of the country and IR depends heavily on energy obtained by burning of fossils fuels (see Fig. 4). The trains either are run by burning diesel or by electricity produced in coal
Fig. 4. Source: Banerjee, White Paper on Indian Railways (2009).
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Fig. 5. Source UIC (2005).
based thermal power plants. The more we burn fossil fuels for production of energy, the more we pump green house gasses mainly carbon dioxide, methane and nitrous oxide into the atmosphere. The Vision 2020 document is perhaps the first attempt by IR in recognizing carbon mitigation as a corporate objective. It intends to achieve this by critically reviewing the carbon footprints of its projects and striving for energy efficiency in its operations (Banerjee, Vision 2020, 2009). Efforts need to be made to increase the share of rail transport viz-a-viz roads. The choice of traction for railroads is a critical policy decision. Globally, countries have evolved their own strategies either to run diesel locomotive hauled trains, or to run electric locomotive hauled trains that draw power from the overhead traction wires. While on one hand, countries like US and Canada have been predominantly retained diesel traction on its major routes; European countries like Switzerland, France, Germany, etc. that have surplus electricity, are importers of oil and have smaller networks have been on the forefront of electrification of their rail routes. Although for UK, as per their policy statement the case of network wide electrification has been kept in abeyance because the case depends on the decline of carbon foot printing of electric generation and low carbon, self powered trains, neither of which can be forecasted at present (Hope, 2010). The graph below shows the percentage of network electrified in various European countries (see Fig. 5). Transport is a challenging sector and does not respect administrative boundaries and therefore decisions are contested across administrative frontiers (Marsden and Rye, 2010). Continuing fiscal and resource pressures, new rail technologies, and environmental consciousness are forcing the railways to reconsider the policies. However, major investments should be made after a clear and accurate portrayal of the full costs of each mode because it has long term implications. Full costs also include the social costs and environment cost. Although it is universally accepted that electric traction is more appropriate for climate change consciousness its implications in Indian conditions are little understood. As mentioned by Baker et al. the earlier climate change models do not sufficiently capture how transport is embedded in people’s social and economic relationships and how they are likely to shift with changing transport provision (Baker et al., 2010). Our research tries to address these aspects in the Indian Railway scenario. Technical considerations for choice of traction IR today has a fleet of about 9000 locomotives, with approximately 4500 each of diesel and electric type, for running its mainline services on the broad gauge network. The fuel bill for IR is about Rupees157K million with 100K million being spent for diesel and the balance for electric energy (I. Railways, ASS 2011–12, 2012).Presently 35% of the freight and 51% of the passenger traffic is hauled by diesel locos and the rest by electric locos (Railways, Year Book 2011–12, 2012). Before we evaluate the option of traction for IR from an economic perspective, we can compare the relative merits and de merits of both the
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electric and diesel locos from a technical perspective on the following technical parameters: technology, efficiency, operational flexibility, pollution, maintenance and line capacity. Technology Electric locos are lighter and have fewer moving parts as compared to diesels and are therefore easier to maintain. The lightness makes them more track friendly but the additional weight gives the diesel locos higher tractive effort or the ability to start heavier trains. The modern diesels of IR have switched over faster to the highly efficient AC–AC transmission and IGBT (integrated gate bipolar transistor) based technology. These modern diesels more than match the electrics in speed and haulage. In fact, the WDG4 diesel loco with 4500 hp is the only loco on IR, which can start a 5300 T trainload on a gradient of 1:150. Recently a 5500 hp diesel locomotive has also been developed with higher speed potential. Similarly the electric locos have been modified for higher adhesion and thus a higher starting load capability. For the same weight, the diesels can haul 10% higher loads. In terms of speed the electric WAP7 with 6000 hp and with a speed potential of 200 kmph is superior for passenger operations (R. I. Railways, 2001). Efficiency Diesels burn the fuel to produce energy, which is then transformed into electric energy for traction purposes. The efficiency of modern diesels used by IR is about 35%. The Loco to Grid efficiency of an electric loco is 98%. However, as per the ‘Well to Wheel’ approach we need to consider the total efficiency of the electric engine from the power plant to the wheels to compare the two on a level platform. Most of the power plants in India are coal fired and operate at efficiencies of about 30–35%. By the time this electricity reaches the locomotive there are further 10% of transmission losses and 2% losses in the locomotive. Thus, the total efficiency is in the range of 28–30% for electric traction. It can be inferred that on a wells to wheel approach the diesels are marginally more efficient in terms of energy use. Operational flexibility The major advantage of diesel locos is that they can work seamlessly under all conditions and all terrains whereas the electrics can only run in the electrified sections. The requirement of changing locomotives causes delays to trains. The capital cost of laying the OHE is substantial, every 10 km of wired route is equal to the cost of an electric loco. Apart from this any disruption in the grid supply affects the train operation instantaneously. In addition, the capacity of the OHE limits the number of trains that can work in a section due to network effects. The wires are also exposed to adverse weather conditions and require additional maintenance during snowfall; rains etc. spoil the appearance of the surroundings and are prone to theft. The height of these wires also places restrictions on the Maximum Moving Dimensions (MMD) on the rail network and inhibits the increase in height of the freight and passenger cars, leading to loss in carrying capacity for the same length of train. An operational limitation is moving trains where the wired territory ends as matching diesel locomotives have to be provided and this leads to sub-optimal utilization of locomotives. Also there is a need for providing power blocks for the maintenance of the over head equipment and this may reduce the line capacity of the section and any blockage in a section directly affects the throughput if the section is heavily used. The main limitation of a diesel engine is that they have to be fuelled at regular intervals in contrast to electric locos, which can work without any refueling delays. Elaborate arrangements have to be made for moving and storing the fuel for diesel locos. The electrics on the other hand have independence from any such infrastructure. If we compare in terms of sources of power, they can run on electricity produced from any source like coal, gas, diesel, renewable etc. and this is extremely useful for energy security as we move towards renewable energy sources for electricity generation. Diesels are wedded to diesel fuel, however in recent times bio diesel from various sources is also used to blend with the diesel. Pollution The diesel loco, which is a primary producer of electricity, generates black smoke and higher noise as compared to an electric loco (see Fig. 6). On the other hand, the visible pollution from an electric loco is missing. However, the pollution occurs at the electricity generation site i.e. the source – the electricity power plant. The Research wing of IR has carried out a study comparing the pollution from diesel loco and thermal power plants as most of the energy for electric traction in India is obtained from them. The study highlights that the major pollutants from diesel locomotives include only NOx and particulate emissions whereas the major pollutants from thermal power plants include suspended particulate matter (SPM), oxides of nitrogen (NOx), sulfur dioxide (SO2) and ash (Kathpal, 2006). The modern Diesel locos complying to US Environmental Protection Agency (EPA) Tier1 norms are 12% better in particulate emissions and 77% in SO2 emissions (RDSO Railways, 1996). However, the electric traction is more useful for operation in tunnels and underground areas usually for suburban traffic where pollution poses major challenge. The diesel locos also consume about 11 times more lubricating oil than the electrics which is a source of pollution and higher maintenance costs (I. Railways, ASS 2011–12, 2012).
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Fig. 6. Source: www.irfca.org (n.d.).
Maintenance (electric v/s diesel loco) The electric locos have longer schedule periodicity and touch the base shed after 90 days. However, separate trip sheds are required for attention after every trip. Normally diesel locos touch the base shed after 60 days but do not require any attention in between. The modern diesels being produced by IR require touching the home shed after 90 days and are comparable to the electrics. Manpower ratio(number of maintenance staff per loco) for diesel locos is about 5.75 as compared to 4.31 for the electric locos (I. Railways, Indian Railways, 2012). The modern diesel locomotives work with an availability of 91% as compared to the conventional diesels and electric locos which have a target based on 81% availability. Constraint of line capacity If we analyze the Line capacity utilization, which is the ability of the same network to handle more trains or throughput, theoretically, it is expected that line capacity shall improve with electrification of the section. Factually, if we look at the running time of trains after electrification it is evident that the speeds have not gone up and trains are detained for new reasons like traction change i.e. change from diesel to electric locos and vice versa. Line capacity can only increase with seamless movement of trains by using diesel locos or further electrifying the adjoining routes till the originating/terminating stations. In many cases it becomes essential to run diesel under wire for operational flexibility and so the full benefit of electrifying a section is not reaped. Total electrification is not a feasible option because it will expose IR to more risk and make it more vulnerable to traffic disruption. In many cases, the capacity decreases because of additional maintenance blocks requirement during which period the movement of trains is restricted. So, IR has not been able to realize the actual benefit of throughput increase. A viable method of improving the line capacity is by reducing the differential in speeds of passenger and freight trains as these use the same tracks for their operation. The passenger trains on IR move at average speeds of about 55 kmph whereas the speed of freight trains is about 25 kmph. This speed differential on the same track results in loss of line capacity as freight trains have to make way for the time tabled passenger trains. This can be mitigated by right powering of the freight trains by providing higher horsepower locomotives or by double heading the locomotives (use of two locomotives in a multiple unit formation). Another option is to run the passenger trains in shadow blocks i.e. one after the other so that there is no speed differential between subsequent trains. This is however not practical as the punctuality of passenger trains is about 84% and the schedule of the passenger trains have to be devised keeping the needs and preferences of the passengers. The above argument shows that both the diesel and electric locos are technically comparable in their performance and so the decision on the choice of traction is not clear-cut. Economic assessment of choice of traction The operational cost of diesel and electric traction is based on statistics published by the Railways. GTKM (Gross Train Kilo Meters) is the gross load of the train including the weight of the locomotive in tones multiplied by the distance in kilometers. SFC (Specific Fuel Consumption) for diesel locos and is measured in liters of diesel consumed divided by the GTKM in thousands. Similarly the SEC is the Specific Energy Consumption for electric locos and is measured by dividing the electric energy consumed by the GTKM in thousands. Whereas the calculation for diesels is based on actual, the calculation for electrics is an empirical approximation as the energy consumed is common for passenger and freight service and has to be apportioned accordingly. The calculations of traction costs include the fuel, lubricating oil, maintenance of locomotives and maintenance of the Over Head Equipment costs. On the basis of the calculations based on the published
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figures of the Annual statistical Statement of 2010–11, it is evident that electric traction is cheaper in fuel costs by Rs. 0.1 million for every 2 million GTKM’s of traffic hauled equally divided between passenger and freight. Similarly, it is marginally cheaper in lubricating oil consumption but it is costly to operate electric locos and maintain the OHE. However, based on the total GTKM’s of the section as well as its length a complete analysis is conducted. Since fuel, costs are most important their fluctuation has a severe impact on the Rate of Return over 30-year life cycle of the electrification proposal. So on purely financial considerations it may be prudent to run trains on electric traction in case the level of traffic exceeds a minimum threshold level that offsets the initial capital expenditure in electrification of the tracks. Societal considerations for assessment of the choice of traction As mentioned in the studies on the Global Sustainability scenario the social values are centered on a community with strong emphasis of enhancing social equity and protecting the environment (Jaroszweski et al., 2010). Therefore, the climate change initiatives have to be evaluated with respect to their impact on the society. In our analysis we consider the societal considerations in addition to the economic, technological and ecological perspective (Neil Adger et al., 2009). We have adopted a scenario-based approach. The IPCC (2001) describes the scenario as: ‘‘A plausible and often simplified description of how the future may develop, based on a coherent and internally consistent set of assumptions about key driving forces (e.g. rate of technology change, prices) and relationships (Working Group, 2001).’’
If we look at India’s power scenario, in 2011–12 India’s generating capacity was 788 BkWh yet about 300 million citizens did not have electricity. This comprised about 6% of urban population and the balance is rural. The Central electricity authority (CEA) of India has estimated that the base load shortage is about 10.3% and peak load about 12.3% for the year 2011–12. Apart from this India has perhaps the highest T&D loss in the world amounting to about 24% (Power, 2012). If we assume that the economy will grow at 8% and all efforts are made to achieve energy efficiency, the demand in 2020 will be about 1715 BkWh. To make good this shortfall India will need to add capacity @20,000 kWh per year however in the recent years the increase has been about 10,000 kWh per year. It is therefore likely that this shortage will continue in the future and the current fuel mix with coal as the dominant fuel, for producing this electricity will remain (Parekh, 2011). As per estimates IR consumes only about 2% of this electricity for Traction purpose (Committee, 2012). It receives an uninterrupted supply and pays for what it receives i.e. the T&D losses are borne by the utilities. It can be inferred that in case IR did not use electric traction this would have resulted in lesser shortage and electricity available to the industry and agriculture. Industry and agriculture on the other hand for their consumption are using less efficient diesel engines to generate electricity. So this argument can be understood in terms of rail electrification contributing to dieselization of the industry, agriculture and domestic sector where inefficient diesel generator sets are providing the electricity at double the cost and increased pollution. Thus, in electricity constrained scenario in India, electrification of IR will lead to dieselization of other sectors. If we look at the oil situation in India, about 70% of the fuel requirement in India is met through imports. Domestic Diesel Consumption has been enjoying a subsidy by the government. However, in January 2013 the subsidy on diesel for the bulk consumers like Indian Railways has been withdrawn which has made diesel expensive by about 20%. Fuel costs contribute towards 18% of the revenue expenditure of Indian railways and this increase has shifted the economics of traction in favor of electrification. However, as mentioned earlier the forced dieselization of agriculture and domestic sector translates into increased flow of subsidies from the Government to the agricultural and industrial sector at the cost of Indian Railways. In addition, if we look at the transport sector in India, the share of rail transport has reduced whereas the transport sector per se has increased thereby increasing diesel consumption at lower subsidized rates. Carrying the argument further to the concept of equity, it translates into contributing to non-availability of basic electricity to rural India at the cost of rail travel. In view of this, the electrification of railway should be coordinated and linked to the electrification of the country and a careful prioritization of sectors for electricity distribution in case of a capacity constrained electricity generation has to be undertaken. The resilience of the network in case of an accident is an important factor to be considered in this evaluation. This can be interpreted as the time taken to restore the operations after disruption. In an electrified section, the restoration after an accident takes a longer time as the catenaries’ (over head wires which carry the electric power) have to be slewed to make place for the breakdown cranes to function. This takes an additional 45 min before and after the restoration and requires extra work force and coordination to do this task. In case of damage to the over-head equipment or the masts, the time and costs can be higher. As far as the passengers are concerned, it means higher time delay costs and decrease in the throughput as all the traffic is blocked on the route. An important element for sustainable development scenario is the need to manage effectively long term threats to security of energy supply by reducing the exposure to the risk of supply disruptions by a combination of diversification and demand reduction (Turton, 2006). In the present case when there is a grid failure it brings the operation to a halt. This total dependence on electrification can expose the railway to sabotage as well. Thus, an electrified network is less resilient and
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Fig. 7. Scenario analysis for IR Electrification decision.
Fig. 8. Ref: Limited (2007).
vulnerable. The network becomes more resilient if certain numbers of diesel locomotives are run by diversifying the traction portfolio (see Fig. 7). The business as usual with a judicious mix of diesel and electric traction can help solve the anomalies. The proposed systems consists of running a few scheduled passenger trains on diesel and also freight trains above a certain threshold limit on diesel even after electrification of the section. There is high volatility in energy consumption for electrified sector. Railways traction electric energy charges are calculated in three parts. Railways ascertain a maximum contract demand in kilo Volt Amperes for each substation based and pay a minimum guaranteed amount for the maximum demand (MD) in Rupees per KVA. There is a penalty if the demand goes over and so railways take a liberal view while ascertaining the requirement. The graph below shows the fluctuation in the demanded quantity over a three year period for a typical substation. Similar fluctuations are noted in a 24 h cycle daily as the trains run vary from day to day. Apart from this an energy usage charge per unit is paid for the actual energy consumed. There is a penalty if power factor falls below a specified value. Billing Demand is therefore a certain percentage of contract demand or the actual MD whichever is higher. Excess over Contract Demand and corresponding units of energy is usually charged at higher tariff (see Fig. 8). The combination of diesel and electric traction can be used in such a way that the volatility of electric traction consumption is reduced. The peaks in the requirements can be pruned down close to the average daily demand by running a few diesel trains at those particular times to reduce the electrical load, thereby lowering the maximum contracted demand of electricity. Another advantage would be that in case of power disruption the availability of diesel locomotives in the section will help in early restoration of operations, thus making it more resilient (see Fig. 8). Indian railways action towards reducing carbon footprints As part of its Vision 2020, IR is committed to take up its mission of setting challenging targets for carbon productivity and to devise a road map to achieve the same in a cost effective manner. It intends to make its operations environment enhancing by over compensating the environmental damage caused by its transport activities by adopting green technologies. IR has already taken up manufacture of efficient locomotives, lighter coaches and wagons, energy audits, use of regenerative braking in suburban trains, setting up of windmill and biodiesel plants, adopting CNG for transport and stationary applications etc. IR is also using its influence to make its vendors, partners and its own units more eco friendly and climate compliant with exacting standards (Banerjee, Vision 2020, 2009). In order to have a modal shift IR has to overcome the bottlenecks in its infrastructure on these routes so as to improve their line capacity or develop alternate routes to serve the traffic needs. Indian Railways carries 55% of the freight traffic and 60% of the passenger traffic on the golden quadrilateral linking the cities of Delhi, Mumbai, Chennai and Kolkata (CRIS n.d.).
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This also implies that rest of the route has spare capacity and there is a need to find traffic to run on these sections. Some of the options available are doubling or quadrupling the lines, making new lines, increasing the carrying capacity of wagons and coaches, running longer trains, upgrading the signaling and track, electrification of the routes etc. Apart from generating capacity these efforts will smoothen the operations which will result in fuel efficiency for IR and resultant reduction in carbon emissions. Two major initiatives under process are the setting up of the Dedicated Freight Corridor’s (DFC) and registering of a few doubling projects under the CDM scheme. It has been estimated that the Western DFC alone would reduce CO2 emissions by 81%. The net reductions are expected to be 68.61 MT of CO2 in the year 2046 (Pangotra and Shukla, 2012). Not only this IR has set specific targets for fuel efficiency, use of non conventional energy sources, improved utilization of rolling stock, execution of doubling and other projects and manufacture of new design rolling stock in its Results framework document (RFD) which is monitored by the Planning Commission. IR seems to be on the right path to address the concern of end use efficiency (Placeholder1). Conclusion India has shown its commitment to reducing carbon emission intensity of its economy and has promised the International community that it will undertake measures in this direction. India’s logistics infrastructure is ill equipped, insufficient and ill designed to support the expected 7–8% growth till 2020. India has an opportunity to address this as most of the infrastructure network is yet to be built. Learning from the past and adopting best practices India should build its infrastructure in a manner that integrates the various modes at the same time prioritizing higher return projects in the efficient modes. Presently, Transport development is being done in silos and there are always last mile connectivity issues. All the stakeholders which includes policy makers, regulators, service providers, resource holders, end users, etc. should plan and act together to achieve this. As far as IR is concerned it needs to realize its potential as the most efficient mode of transport in India in terms of fuel, land usage and carbon footprints and it has to petition for greater financial support from the Government. This is essential otherwise; its share in the transport sector will come down even further. The funds it receives have to be gainfully utilized for its projects that improve line capacity. Although cost plays a little role in the choice of modes there is a need to bring about policy interventions to internalize the external costs of each mode to bear the social costs so that a socially optimal modal shift can be achieved. Even within a mode there is a need to separately cost the freight and passenger business. This would ensure that there is no cross subsidization of the passenger transport by the railways by using the profits generated from the freight business. Through these sustained efforts only will IR be able to gain share of traffic from other modes. The evidence from the study suggests that the diesel and electric locos plying on IR have their relative merits and demerits but are comparable in their performance. With the current trend and sanction of Electrification, IR will electrify about 60% of its network in the next 6–8 years. Although the operational cost of electric locos is lesser but the initial capital, required for electrifying the network is high. With all the major routes already electrified, the benefit of such operational savings is reducing as new sections that are being considered for electrification have less traffic density. Till the fuel mix of power production remains the same i.e. coal dominated and there is a shortage of electricity in the country, the carbon footprints of running electric locos will be higher. The opportunity costs of the investment in electrification are also high. It is concluded that IR should not further proliferate Electrification of its routes but should strengthen the infrastructure on the existing routes by doubling them etc. There should be a judicious mix of both the tractions to achieve operational flexibility and efficiency. IR should continue to endeavor to improve the energy efficiency of its locomotives during driving, minimizing fuel consumption, optimizing load factor, and improving design of coaches and wagons to reduce the operational costs and carbon footprints. Considering a macro view, also it is important for the Government to have an integrated transport development plan and to come up with policies and incentives for bringing about a modal shift towards Railways Transport strategy must cut across modes of transport, administrative and geographical boundaries and should integrate capital investment with regulatory and policy development. Although strategy should be made for the long term it should be dynamic and flexible enough to respond to the ongoing changes like the advent of alternate fuels etc which would alter the efficacy of the transportation alternative (Planning Commission, 2014). As per the IPCC assessment reports the global temperature rise is imminent and it is imperative that the transport policies also look at adaptation strategies. This is of prime importance as most of the Asian countries are in the process of expanding their transport infrastructure. Transport infrastructure including that of railways is adversely affected by extreme weather like flooding, storms etc. It is easier to introduce these adaptive measures at an early stage by carrying out a risk/ vulnerability analysis and environment impact assessment (Regmi and Hanaoka, 2011) as spatial plans are difficult to revise and there are many players involved in their development. References Baker, C.J., Chapman, L., Quinn, A., Dobney, K., 2010. Climate change and the railway industry: a review. J. Mech. Eng. Sci. 224 (3), 519–528. Banerjee, Mamta, 2009. Vision 2020. Ministry of Railways, New Delhi. Banerjee, Mamta, 2009. White Paper on Indian Railways. Ministry of Railways, New Delhi. Chapman, Lee, 2007. Transport and climate change: a review. J. Transport Geogr., 354–367. Committee, 2012. Indian member. India energy book.
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CRIS, 2012.