T41e Cities, transportation and energy
Preparation meeting in november 2009
China-Europa Forum catalogue
Sustainable mobility is a new challenge for urban transport. 40 % of the French flows of passengers and 53% of the emissions of gas with greenhouse effects by transport activities occur in cities. Minimization of energy consumption and CO2 emissions in such complex systems need cooperation between public and private stakeholders to define and undertake actions and to evaluate evolutions.
To achieve cost-benefits analysis in transport domains, many efforts have been made to give a monetary value to the improvements of security and accessibility (reduction of travel times and congestion) to compare them with the investment and operation expenses. The comparisons of the efficiency and CO2 emissions of different transport modes are still limited to the effects of the choices of individuals between private car and public transport (eg http://www5.ratp.info , http://www2.ademe.fr/calculette-eco… ) The methods to compare the consequences on the climate of public decisions about organization of transport, traffic management, urban and transport planning are still to be invented and tested. The data necessary to make appropriate calculations will probably come from different actors, which means, that it is practically impossible to do these comparisons until they cooperate to share and distribute these data.
Topics for debates
Examples of questions from Europe proposed to the workshop:
Development of cities and “urban sprawling” is considered by many observers as the first cause of the increase of CO2 emissions and therefore as unsustainable. Some people think that densification of the existing urban structure is possible without reducing the quality of life for inhabitants. Case studies of the impact on transport needs of different types of density could be examined and if possible some recommendations proposed for implementation of daily facilities (commerce, services…) in housing districts and creation of housing units in highly specialised areas (airports, university campus, industrial parks …)
Responsibilities on urban planning and transport systems planning, funding and operating are traditionally in the hands of territorial authorities of different levels (province, cities, towns) and the cooperation between them is relatively difficult to organize. What could be the role of national authorities to facilitate the negociations around this question ? In particular, is it possible to identify some functions who absolutely need shared responsibilities, for instance the management of a multimodal node like a railway station when urban, regional and interregional trains are stopping there ? Is it possible to make the list of decisions necessary to guarantee or even to improve the service offered to all kind of users by a large station, including the area around it, which could attract many new activities ? Is it possible to recommend appropriate organizations to assure that these decisions will be taken in a consistent way ?
How to optimize the use of roads by light rail or BRT, private cars, taxis, buses and lorries ? What are the effects of specific systems like traffic signal priorities ?
How to promote the use of public transport, car sharing, car pooling, bicycle (owned by the passenger or not) ? Is walking considered as a transport mode and respected accordingly ?
The emissions of a car depends both on its own specifications but also on the kind of driving conditions imposed by the traffic. How to characterise these conditions, for instance the number of cycles of acceleration/deceleration ? Is it possible to deduce these elements from the data currently collected by traffic management centres to forecast the travel times ? If it is not possible, what kind of sensors could provide missing data ?
Is it possible , with new algorithms applied to already collected data, to calculate the CO2 emissions of a road network at a given moment, and to analyse the evolution of this parameter in relation with the type of period concerned (hour in the day, day in the week , specific event , weather…) and the traffic management strategy applied. If it is not possible, what kind of systems could be imagined, especially cooperative systems ? The “emission factor” of a public transport system ( i.e. CO2 emission due to the transportation of a new supplementary passenger, for instance on a bus line) depends on the occupation rate of the vehicles. How to optimise a whole public transport system with different transport modes (train, metros, tramway, bus..) to reduce the emissions and how to increase acceptance by the travellers (number and type of commutations, ticketing, tariffs, information…) ?
How new technologies (ITS intelligent transport systems) could help to identify new behaviours of mobility (in connexion with traditional mobility surveys) and eventually participate to the emergence of new services with verifiable positive impacts on CO2 emissions ? What are the elements concerning transport (like emission factors, average travel times to join a given address … ) necessary to build a mobility plan for a “traffic generator” with consideration of CO2 emissions ?
The workshop could identify the elements of methodology used in existing projects and evaluation tools in Europe and China and make proposals for their promotion and eventual combination. The first result of this action will be a set of case studies with details on the context, the objective of the project and its evaluation, the methodologies used and the available results. The workshop could also make recommendations on the organization needed to give a sufficient perenniality to the methods on which public decisions with long term effects will be based. Further work could address the relationship between urban planning and transport organization: How to evaluate the consequences of urban sprawling in terms of energy and emissions, how to create the conditions of cooperation between public and private actors involved in the implementation of activities to choose places where the end users will at the same time benefit and contribute from/to a better accessibility.
- on Nov, 10-13, 2009 in Shanghai in the Sino-French Center of TONGJI University : The preparatory session of the workshop will take place in synergy with the second session of the Forum on Transport with High Level of Service (programme, pdf 79 Ko) organized in the frame of the Sino-French agreement on sustainable urban development, signed in 2007 between Chinese Minister of Housing and Urban & Rural Development and French Minister for Ecology, Energy, Sustainable Development and Land Planning, aiming to facilitate exchange of good practice between experts and decision makers of both countries.