Title: Case study: Improving public transport supply
1Case study Improving public transport supply
- Odd I Larsen, HiMolde
- CBA-course, Molde, Dec, 2006
2A digression on interdependent projects or
measures
- In transport as well as other fields we may have
several investments projects or other measures
under consideration. - Interdependence we might in a formal way state
as NPV(A) NPV(B) ? NPV(A U B) - i.e. the net present value of project A added to
the present situation (without B) the net
present value of project B (without A) is
different from the net present value of both
projects added to the present situation. - Interdependence usually stems from the benefit
side, but there may also be cases where
construction or operating costs are involved. -
3How do we handle this situation?
- We must investigate all permutations of projects
to arrive at the combination with the highest
NPV. - This investigation will also tell us what are the
best way of phasing the projects in time
(provided that they can not be completed at the
same time.)
4A real example 4 road projects in Oslo
Annual benefits of four projects when they are
added as the first and the last to the present
network. (Mill NOK )1)
1) Value of time savings and savings in vehicle
operating cost.
5Example based on a stylized model
15 km one hour morning peak
CBD
Suburb
Base case buses delayed by congestion
6Measures
Discreet policy measures tested (with optimised
policy variables).
7(No Transcript)
8Prelimenaries PT supply and pricing
- Public transport is a service
- From the users standpoint the quality of the
service depends on several factors- The density
of the routes (influences walking distances to
and from stops.- Frequency of services
(influences waiting times and scheduling of
activities).- Crowding (influences comfort)-
Design of the system (influences the number of
transfers etc).- Hours of operation per day-
Running speed (influences onboard time) - General quality is difficult to measure due to
the many dimensions and we must usually simplify
to measurable dimensions. - CBA can be used for specific changes in supply,
i.e. a new urban rail line, a new bus route, but
we usually need a comprehensive transport model
to evaluate the impacts on demand.
9Improved quality of a service shifts the demand
curve
10Number of revenue kilometres operated per hour
a proxy for some aspects of quality (waiting,
walking and possibly transfers).
- Empirical work (econometric studies) have shown
that revenue kilometres operated per unit of time
affects demand. Elasticity of demand lt 0.3 0.6
gt. - CBA analysis of a general improvement in the
quality of PT-services assuming that additional
revenue kilometres are added in the most
efficient way.
11Structure of urban PT-service
Add. peak service
Basic service
Lower cost per rev.km for basic service than for
additional peak service
123 categories of demand
- The peak demand that dimensions the total
capacity (number of vehicles, drivers etc). - Other peak demand
- Off-peak demand
13Questions?
- How should we determine rev. kms per hour for
basic services and additional peak services? - What is the appropriate fare structure?
- What is the appropriate capacity per revenue
kilometre? - Objective Maximize social surplus of the
PT-system. - Additional concerns- Sufficient capacity- Cost
of public funds- Transfer of car drivers and
external costs of car use
14Model of PT-system i Oslo
- 3 demand functions, one for each category of
demand. - Cost function depending capital and operating
cost per vehicle for peak and basic services and
fixed cost per passenger (ticketing) and capacity
of vehicles. - Consumer surplus for PT-users
- Benefits of transferring car drivers
- Constraints on utilization of capacity
- Cost of public funds
15Maximising social surplus - no concern for car
traffic
16Maximising social surplus - accounting for
impacts on car traffic
172. Best gt congestion and no congestion pricing