XXII SIDT National Scientific SeminarBari, 14-15 settembre 2017Technologies and Methods in Railway Transport
Innovative o-d based rail freight subsidies compensating infrastructural gaps: methodological issues and practical
implementation in Italy
Daniela Tocchi, Vittorio Marzano, Andrea PapolaDepartment of Civil, Architectural
and Environmental Engineering, University of Naples Federico II
Dario AponteRAM - Rete Autostrade Mediterranee
Fulvio SimonelliUniversity of Sannio, Department of Engineering
Motivation and background
• rail freight transport largely acknowledged as potentially cost-effective and environmentally sustainable
• many EU policies and funds to support rail freight and improve performance of EU freight railway network
• Italy:
– up to 2014: dramatic decreasing trend (-50% w.r.t. 2007 traffic)
– since 2015: an integrated set of policies to relaunch rail freight, based on three pillars:
• infrastructure improvements
• regulation/simplification
• incentives
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Incentive-based policies in Italy
• earlier incentives (2005-2007): L 166/02
• ferrobonus (2010 – to date): to shippers and MTOs
– compensation of 1.08 €/train∙km for new services
– positive impact: +17% increase in rail freight traffic in 2012 w.r.t. 2009
– re-newed by the Italian Government for 2017-2021, up to 2.5 €/train∙km
• sconto pedaggio (2015 – to date): to railway undertakings
– discount of the access charge to the rail infrastructure manager
– based on former state aids to the ex incumbent operator Trenitalia Cargo
– watering-can principle, irrespective of network performances
– up to 2.5 €/train∙km for train services on the entire Italian rail network
– additional incentive to/from South (larger market share of Trenitalia Cargo)
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An equitable sconto pedaggio
• research question: watering-can distribution not leading to equitable market conditions for railway undertakings
– performance of the Italian freight rail network very heterogeneous amongst o-d pairs
– railway undertakings receive the same incentive irrespective of the infrastructural gap with respect to EU standard
• 750 metres, 2000 tons, PC80 gauge
• proposition of an equitable sconto pedaggio:
– an o-d pair basis incentive
– proportional to the infrastructural gap on the o-d pair with respect to the performance of the EU-standard freight train
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An equitable sconto pedaggio: definition
INFRASTRUCTURAL CHARACTERISTICS
permissible train weight (wtk)
maximum train length (ltk)
loading gauge (gtk)
slope (stk)
current scenario
cwunittk= ctot
tk/captk
EU standard scenariocwunti,opt
tk = ctot,opttk / capopt
tk cwunittk
• ctottk total cost to operate the train t on the path k
• captk train payload capacity
• performance of a freight train of type t (e.g. intermodal) on path k
OPERATIONAL CHARACTERISTICS
number of locomotives nloc
locomotive weight wtloc
locomotive length ltloc
freight railcar total weight wtcar
unladen weight wutcar
freight railcar length ltcar
unit weight cost
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Infrastructural gap and proposed incentive
• proposed unit incentive per o-d pair:
inckmtod = min{ ∙cdunit,gap
tod , ∙km}
EU regulation on cap for incentives
• weight cost units (€/ton):
– cwunit,gaptod = minkKod{cwunit
tk}– minkKod{cwunit,opttk}
• distance units (€/train·km)
– cdunit,gaptod = cwunit,gap
tod ∙ cap*tk/tdod
• tdod , travel distance between o and d
• cap*tk ,capacity of path k* minimizing the cwunit
tk cost
public budget constraint
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Calculation of train capacity
Calculation of corresponding:
• maximum number of freight railcar
• candidate train weight
Hypotesize max length ltk = lk
Consistency with weight upper bounds :
• maximum permissible weight per axle
• slope and power traction (# locomotives )
Yes length is the limit
Calculate payload capacity
No weight is the limit
Consistent with maximum permissible
weight, calculation of:
• corresponding number of railcars
• maximum train length
Necessary condition for train t to operate on k: gk gtmin
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Calculation of train costs
• cost of train driver(s) cdriv = ndriv∙ttk∙ch
driv
– number of drivers ndriv
– chdriv hourly cost rate
• cost of locomotives cloc= nloc∙ttk∙ch
loc
– chloc hourly cost of locomotive
• cost of rolling stock ccar= ncars(ltk)∙ttk∙ch
car(gk)
– ncars(ltk) number of railcars allowed by train length ltk
– chcar(gk) hourly cost of rolling stock
• energy consumption and toll payment cnetw =km(wtk)∙tdk
– tdk = vt∙ttk travel distance between o and d along k
• other fixed costs (shunting costs, fixed administrative costs, etc.) cfix
ctottk = [ndriv∙c
hdriv + nloc∙c
hloc + ncars(ltk) ∙ch
car(gk) +km(wtk)∙vt]∙ttk + cfix
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Quantification of the incentive
• the proposed incentive requires calculation of shortest unit path costs in the current and optimal scenarios
• a non-additive shortest path problem:
– total cost ctottk and capacity captk based on performance of worst link for
each of the relevant infrastructural characteristics (path-based costs)
• possible approaches:
– brute force: enumerating all paths for each o-d pair and then calculating the corresponding train capacity and costs, practically infeasible also for small-size networks
– more efficient solution algorithms …
• key aspect: homogeneous infrastructural characteristics across links of the network imply homogeneous train performances irrespective of the specific path k …
• … thus additive shortest path algorithms can be applied8
Shortest path calculation
Rationale:
1. discretize relevant infrastructural characteristics according to a limited number of thresholds:
– L set of nl train length thresholds (as example nl=5 thresholds L≡{750 m, 600 m, 500 m, 400 m, 300 m})
– G set of ng loading gauge thresholds
– S set of ns slope thresholds
– W set of nw permissible weight thresholds
2. define a set containing all n=ng∙nl∙ns∙nw combinations of thresholds
– the generic combination i defines an appropriate bound for infrastructural characteristics
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Quantification of the incentive
3. identify subset AiA of links of the network with at least the characteristics defined by i
4. hypotesize homogeneous characteristics defined by i for all links in Ai
5. calculate the lowest unit cost paths on Ai via standard additive shortest path algorithms
• iterating across yields the global shortest unit path cost with the corresponding best infrastructural performances
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Algorithm
• ꓯ # locomotives (nloc)
• Step 1 – calculation of shortest paths and unit costs in the current scenario
• Step 2 – calculation of the optimal cost and of the infrastructural gap
• Repeat Step #1 for the EU standard combination of infrastructural characteristics
• Step 3 – quantification of the incentive
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Case study: Italy (baseline 2015)
operational costs
• cost of train driver(s): ndriv=2 (according to the Italian regulations); chdriv=25 €/h (gross yearly salary of
55.000 €; 2200 working hours/year)
• cost of locomotives: chloc=22.83 €/h
• cost of rolling stock: chcar=0.36 €/h for a standard railcar; ch
car=0.43 €/h for a low-loader railcar
• energy consumption and toll payment:km=3.26 €/train∙km (toll accounts for 2.82 €/train∙km);km is
assumed independent of the train weight
• fixed costs: 2200 €/trip for shunting in origin and destination; 200 €/trip for administrative costs
160 combinations of infrastructural
characteristics
• length: nl=5, set L≡{700 m, 600 m, 500 m, 400 m,
300 m}
• loading gauge: ng=4, set G≡{PC80, PC45, PC22,
PC00}
• slope: ns=4, set S≡{10‰, 15‰, 21‰, 50‰}
• weight: nw=2, set W≡{8.0 tons/m, 2.0 tons/m}
intermodal train characteristics
• locomotive:
• mass wtloc=106 tons
• length llloc=18 m
• freight railcar:
• total weight wcar=50 tons
• unladen weight wutcar =17.5 tons
• length lcar=20 m
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Case study: implementation in Italy
• 90% of o-d pairs: infrastructural gap lower than 0.20 €/TEU∙km• only apparently low: ~ 200 €/TEU for a 1000 km o-d pair
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Case study: implementation in Italy
smart incentive
mean st. dev. M€/year
0-49 12% 0.14 0.23 23.28
50-99 5% 0.10 0.08 10.18
100-199 12% 0.14 0.27 23.29
200-499 12% 0.13 0.20 18.16
500 and more 58% 0.10 0.05 48.58
total 100% 0.14 0.22 123.49
infrastructural gap [€/TEU km]# trains/year
per o-d pair
# trains/year
% distribution
• o-d pairs clustered by # trains/year
cost of the “intermodal divide” of railway transport
in Italy with respect to the ideal standards of the EU
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Conclusions and research prospects
• an o-d equitable incentive to railway undertakings:
– operational
– dynamic: adjustable on a yearly basis to account for ongoing network improvements
• main challenge: non-additive costs → ad hoc procedure to calculate shortest paths
• research prospects:
– embedding demand-side effects: modal split effect and generated demand effect
– as objective function to maximize the modal shift
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XXII SIDT National Scientific SeminarBari, 14-15 settembre 2017Technologies and Methods in Railway Transport
Thanks for your attention
Calculation of train capacity
• maximum number of freight railcar
• candidate train weight
–
• consistency with weight upper bounds:
– wtk wk∙ltk
– wtk wtk(nloc, sk)=t(sk) ∙ (nloc)
• (Yes) w*tk min{wk∙ltk , t(sk)∙(nloc)}
• (No) wtk = min{wk∙ltk , t(sk)∙(nloc)}
• number of railcars
• maximum train length
• train payload capacity
– Captk=wtk -ncars wucar -nloc wloc
tcar
tloclockcars
l
lnln int
w*tk = nloc∙wtloc +ncars∙wtcar = nloc∙wtloc +
tcar
tloclock
l
lnlint ∙wtcar
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