How Can P and R Facilities Contribute to Reduced Emissions of Greenhouse Gases?
Nominated for The Planning for Sustainable Land Use and Transport Award
Jan Usterud Hanssen, Institute of Transport Economics, Aud Tennoy, Institute of Transport Ecocnmics, Petter Christiansen, Institute of Transport Economics
Park and Ride have an effect on the volume of traffic and the effect on greenhouse gas emissions. We discuss what factors are important to evaluate and what measures to consider in order to reduce vehicle kilometres travelled.
Planners and politicians often want to build new P&R facilities or expand existing ones in order to satisfy a revealed demand for parking near stations, terminals or bus stops. The justifications for new capacity should be based on knowledge about the users, their alternative transport opportunities and the environmental impacts of the alternatives for the whole journey. These impacts may be local or global. Because parking where commuters and others can transfer to public transport often is free (i.e. to the users), this may induce "unnecessary" use of the car for access to the transfer points or for access to the public transports services.
We have studied the users and use of parking spaces connected to the regional public transport system at 73 locations around major Norwegian cities. We have also interviewed travellers at 23 stations. Based on findings from these studies, we have defined factors that influence on the choices made by the travellers. These factors are: fare structure, access roads, frequency, capacity (on roads and public transport), total travel time, etc. The study indicates that free parking at transfer points may induce some very short car trips. Some of these can be replaced by walking or bicycling or with local bus services without significant loss of time for the traveller.
We are discussing the implications of P&R for land use, mode choice and urban sprawl and the total number of vehicle miles travelled. If the alternative for only a small part of the users of P&R is to use the car for the whole journey, the parking facility may cause a reduction of the total volume of vehicle miles travelled and therefore also a reduction of GHG emissions. Based on the analysis of the residential patterns of the users of P&R, the use of the existing facilities and knowledge about the public transport system, we have formulated a number of questions that should be asked (and answered) before making a decision on whether to expand the P&R capacity in a given location or not. The answers will of course vary with the location of the transfer point, its catchment area served and the distance travelled with public transport.
Association for European Transport