E-VRPTW benchmark instances (Schneider, Stenger & Goeke, 2014)
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These files are a small sample of the E-VRPTW instances introduced in:

  M. Schneider, A. Stenger and D. Goeke.
  "The Electric Vehicle-Routing Problem with Time Windows and
   Recharging Stations". Transportation Science 48(4): 500-520, 2014.

The instances are derived from Solomon's VRPTW benchmark, adding a set of
charging stations (recharging stations) and battery/energy parameters.

File format (whitespace-separated columns)
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  StringID    Type   x    y    demand  ReadyTime  DueDate  ServiceTime

  - StringID : node identifier (D0 = depot, S* = charging station, C* = customer)
  - Type     : d = depot, f = charging (fuel) station, c = customer
  - x, y     : coordinates
  - demand   : customer demand (0 for depot/stations)
  - ReadyTime: earliest service time (time-window lower bound)
  - DueDate  : latest service time (time-window upper bound)
  - ServiceTime: service duration at the node

The trailing lines of each file give the vehicle/energy parameters, typically:
  - vehicle capacity (load)
  - battery capacity (energy) and energy consumption rate
  - battery recharging rate (energy per unit time)

Source: https://github.com/jmanzolli/E-VRPTW (CPLEX data derived from the
Schneider et al. benchmark). See the bibliography for the original reference.