The National Transport ModelPredictions on Trends in Road Transport

Philipp Thiessen

ITEA Division, Department for Transport

Philipp Thiessen

ITEA Division, Department for Transport

Structure of presentation

• What is the National Transport Model?

• How does the National Transport Model work?

• NTM uses over time

• Traffic and emission forecasts and their key drivers

• Sub-national use of NTM forecasts

• What is the National Transport Model?

• How does the National Transport Model work?

• NTM uses over time

• Traffic and emission forecasts and their key drivers

• Sub-national use of NTM forecasts

What is the National Transport Model for?

• Forecasts the main transport indicators of congestion, pollution and patronage

• Supports policy making by providing a multi-modal framework for understanding the impact of different scenarios.

• Recent use includes the Eddington Study, Road pricing feasibility study, and recent road traffic forecasts.

• Forecasts the main transport indicators of congestion, pollution and patronage

• Supports policy making by providing a multi-modal framework for understanding the impact of different scenarios.

• Recent use includes the Eddington Study, Road pricing feasibility study, and recent road traffic forecasts.

What are the capabilities of the National Transport Model?

• A strategic policy and scenario testing tool

Contains all trips and traffic in GB.

Operates using detailed network models

But, not suited to analysis of individual roads/areas.

• A multi-modal model

Comprising 6 modes: car driver, car passenger, rail, bus, walk and cycle.

• Provides Projections of transport demand and emissions

Produces forecasts of the number of person trips by distance, journey purpose and mode

• Forecasts always include an element of uncertainty

But, peer review has shown the NTM is fit for purpose!

How does the National Transport Model work?

• NTM is a 4-stage multi-modal model

• It estimates demand through a bottom up model of travel

behaviour

• NTM is a 4-stage multi-modal model

• It estimates demand through a bottom up model of travel

behaviourHow many trips do people make

Where do people make trips to and from

What mode do they use to make those trips

What route is chosen across the network

Overview of the National Transport Model

Socio-Demographic Inputs•Land use•Employment

•Population

•Income

•Driving licenses

•Car purchase price

Socio-Demographic Inputs•Land use•Employment

•Population

•Income

•Driving licenses

•Car purchase price

Rail

Model

Road

Traffic

Model

Traffic Growth Rail Growth

Congestion Overcrowding

Freight

Model

RailPolicy

RoadPolicy Local Transport

Policy

FreightPolicy

Bus

CycleWalk

Car

ownership

model

Trip end

model

Road Traffic Data

•Traffic Counts

•Fuel Costs

•Vehicle Efficiencies

•Vehicle Emissions

Rail Data

•Ticket Sales

•Revenue

•Timetable and

rolling stock data

Multi

Modal

Demand

Model

Number

and location

of trips

NTM – Use over time

• In its first form, the NTM was developed solely for traffic forecasting.

• More recently: focus on congestion and the economic costs

of time lost in traffic (example of road pricing)

• With the environment being a key concern, modelling of transport emissions now a key focus.

• In its first form, the NTM was developed solely for traffic forecasting.

• More recently: focus on congestion and the economic costs

of time lost in traffic (example of road pricing)

• With the environment being a key concern, modelling of transport emissions now a key focus.

Focus on Congestion:‘marginal social cost’ road pricing

2025 No road pricing 2025 With road pricing

Pricing on the roads

offers potential

benefits of up to £28

billion a year in 2025

Compared to 2025

without road pricing

Traffic & CO2 -7%

Congestion - 50%

Benefits come from

getting relative prices

right – not pricing

everyone off the road

Emissions in the NTM

• Speed/flow curves determine speeds, link by link

• Speed/emission curves – for each vehicle/fuel type

• Curves move down over time with improved engine technology

• At link level and for different time periods speeds and vehicle flows

determine emissions

• Total emissions are the aggregation over road & vehicle types and time periods.

• Speed/flow curves determine speeds, link by link

• Speed/emission curves – for each vehicle/fuel type

• Curves move down over time with improved engine technology

• At link level and for different time periods speeds and vehicle flows

determine emissions

• Total emissions are the aggregation over road & vehicle types and time periods.

NTM Forecasts

Traffic and congestion continue growing; CO2 to stabilise and air pollutants continue falling as engine improvements

filter through to entire fleet.

CO

2

PM

10

NO

X

High 39% 48% 7% -11% -50% -58%

Central 31% 28% 4% -5% -53% -60%

Low 20% 19% 3% 1% -55% -62%

England,

Forecasted

Changes

2003 to 2025 Sce

nari

o

Tra

ffic

(Veh

icle

km

)

Co

ng

esti

on Road Traffic

Emissions

2025 forecasts

Av. Jo

urn

ey

Tim

e

NTM Emissions Forecast

0

20

40

60

80

100

120

140

160

1980 1985 1990 1995 2000 2005 2010 2015 2020 2025

Index (

1980=

100)

CO2

PM10

NOX

Historic Data Forecast

Key Drivers of Forecast

Continued traffic growth, but at a slowing rate: Rising income,

rising, but ageing population and falling cost of driving (fuel economy improvements)

Carbon: Fuel economy improvements, biofuels

Pollutants: Increasingly stringent pollutant standards and old,

dirty cars dropping out of the fleet

Continued traffic growth, but at a slowing rate: Rising income,

rising, but ageing population and falling cost of driving (fuel economy improvements)

Carbon: Fuel economy improvements, biofuels

Pollutants: Increasingly stringent pollutant standards and old,

dirty cars dropping out of the fleet

Use of NTM at sub-national level

• The NTM is essentially a national GB model and peer-reviewed as ‘fit for purpose’ at this level.

• All assumptions are set at national average (e.g. vehicle fleet).

• While results can be supplied at broad regional level, they would not reflect regional variations in assumptions

• We are currently evaluating the accuracy of sub-national results through a comparison to regional models.

• The NTM is essentially a national GB model and peer-reviewed as ‘fit for purpose’ at this level.

• All assumptions are set at national average (e.g. vehicle fleet).

• While results can be supplied at broad regional level, they would not reflect regional variations in assumptions

• We are currently evaluating the accuracy of sub-national results through a comparison to regional models.

Where to Find NTM Outputs

• Eddington Study support paper – 2006

Transport Demand to 2025 & The Economic Case for Road Pricing and Investment

http://www.dft.gov.uk/about/strategy/transportstrategy/eddingtonstudy/researchannexes/researchannexesvolume3/transportdemand

• Road Transport Forecasts for England 2007

http://www.dft.gov.uk/pgr/economics/ntm/071023_AnnualForecast07.pdf

http://www.dft.gov.uk/pgr/economics/ntm/ for link to regional forecast and more detail on NTM

• Eddington Study support paper – 2006

Transport Demand to 2025 & The Economic Case for Road Pricing and Investment

http://www.dft.gov.uk/about/strategy/transportstrategy/eddingtonstudy/researchannexes/researchannexesvolume3/transportdemand

• Road Transport Forecasts for England 2007

http://www.dft.gov.uk/pgr/economics/ntm/071023_AnnualForecast07.pdf

http://www.dft.gov.uk/pgr/economics/ntm/ for link to regional forecast and more detail on NTM