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Environmental protection

Intelligent transport systems have been identified by experts as a potential tool for reducing energy consumption, pollution and greenhouse gas emissions resulting from the movement of people and goods.

Research programmes and projects have been initiated at European and international levels to work on this theme which has only recently come to the fore as ITS were previously only considered as useful for reducing congestion, guaranteeing journey times and improving road safety. The main European initiatives currently in progress come under the European Commission’s 7th Framework Programme with a research objective on ICT (Information and Communication Technologies) for energy efficient and sustainable mobility (see the section on "Research programmes and projects).

Intelligent transport systems can contribute to the protection of the environment using the different strategies set out below:

  • strategies which aim to modify the transport demand
  • strategies which aim to make better use of the transport network and optimise mobility
  • strategies which encourage drivers to adopt more environmentally-friendly driving behaviour

Strategies intended to modify transport demand

A wide range of ITS can be used to modify the transport demand:

- Multimodal information for users before and during their journey allows them to make informed travel choices based on their own personal criteria (comfort, cost, travel time etc.). Given that people usually underestimate the cost of using their own private vehicle and are often unaware of the public transport offer, this may lead to modal shift from private vehicles to other modes of transport.

- Multimodal mobility management allows transport managers to prioritise public transport and soft modes of transport over and above the use of private vehicles. There are several examples in France of multimodal mobility management at city scale (see "ITS in France" opposite).

- Systems to improve the efficiency of public transport can also be considered to contribute to modal shift from private vehicles to more environmentally friendly modes of public transport.

- Shared vehicle management systems (for bicycles and in the near future for electric cars) also contribute to modifying the transport demand by increasing the attractiveness of soft modes of transport and decreasing the benefits of owning one’s own vehicle.

- Variable city or road tolls for the use of transport infrastructure are another means of modifying transport demand which may have a beneficial impact in terms of reducing carbon dioxide and pollutant emissions, as is the case for congestion charges. Electronic toll collection systems which reduce congestion can also help reduce emissions.

- For industrial and freight vehicles, multimodal logistics platforms mean that it is now possible to chose forms of transport other than road vehicles.


Strategies to make best use of the transport network and optimise mobility

Numerous systems have been developed with the aim of optimising mobility. This requires substantial amounts of data to be collected in order to assess real-time traffic flow on road infrastructures. The data collection systems used to this end, such as electromagnetic loops, are often situated directly on the infrastructure and used solely by the infrastructure manager. However, an increasing number of on-board systems are being developed which use data obtained by means of new geolocation technologies.

So-called "cooperative" systems (see opposite) also play an ever-increasing role in collecting data on vehicle trajectories , the road, and weather conditions etc.

The different ITS used to optimise the use of existing road infrastructures are:

- Active traffic management and dynamic speed regulation (see the section on "Road Traffic Management") impact on traffic flows and make it possible to guarantee journey times and reduce congestion which are contributing factors to increased levels of fuel consumption and carbon dioxide emissions. In this sense active traffic management measures can be considered to help protect the environment. This is however somewhat mitigated by the phenomenon of "induced traffic": When drivers see that traffic conditions have improved as the result of the implementation of an active traffic management measure, they may decide to use their car for journeys for which the levels of congestion previously dissuaded them.

- The coordinated management of traffic signals in urban areas is one idea for reducing nuisances by reducing congestion: Once again, attention must be paid to the impact of induced traffic.

- Active parking guidance systems, which mean drivers no longer have to drive around looking for a space thereby needlessly consuming fuel, can also help protect the environment. However, it is acknowledged that parking policies have a significant impact on users choice of mode of transport: Drastically reducing the number of parking spaces available is still the best way of encouraging users to take public transport.

- In terms of freight transport, there are a wide variety of ITS available to improve supply chain efficiency. These are mainly based on geolocation technologies.


Associated pages

Gestion du trafic routier


Strategies which encourage more environmentally-friendly driving behaviour

Drivers’ behaviour at the wheel has an impact on their fuel consumption and the probability of being involved in an accident. So-called eco-driving refers to driving behaviour that respects the environment and other users, and can lead to significant savings in terms of fuel consumption, without affecting journey times.

The golden rules established by the EU’s Ecodrive project are as follows:

  • 1. Move up a gear as quickly as possible.

Move up a gear at 2,000 - 2,500 rpm.

  • 2. Maintain a steady speed.

Drive in the highest gear possible at low rpm.

  • 3. Anticipate traffic flow.

Read the road as far ahead as possible and anticipate the movements of the surrounding traffic.

  • 4. Slow down gradually.

If you need to slow down or stop, do so gradually by easing off the accelerator in good time and keep the car in gear.

  • 5. Check tyre pressure regularly.

tyre pressure 25% below the norm increases rolling resistance by 10% and fuel consumption by 2%.

We now know that eco-driving is complex and needs to be learned and refreshed on a regular basis as the concepts are forgotten over time. Intelligent on-board driving assistance systems are being developed to help drivers reach an "optimal" standard of driving which is both safe and energy efficient. Known as Ecological Driving Assistance System (EDAS), they mainly take the form of on-board systems in vehicles which collect a variety of data on the driver’s behaviour, the road and/or other vehicles. This data is then used to monitor and analyse driving behaviour in order to provide the driver with recommendations which help to self-teach energy saving techniques, without compromising safety.

Research is currently underway to identify the best levers for improving fuel consumption, and innovative technologies are being used to make this advice more widely available. Cooperative systems are of particular interest, but these are still at the developmental stage.


Associated pages

Sécurité routière

Entreprises - Industriels

General documents on ITS for environmental protection

There are several studies, reports and articles available which present methods for estimating the general impact of ITS in terms of reducing fueld consumption, pollution and carbon dioxide emissions:

1. The technical report from the European Commission (DG INFSO) and the Japanese Ministry of the Economy, Commerce and Industry on methodologies for assessing the impact of ITS applications on carbon dioxide emissions, published in March 2009.

Other documents present the results of practical experiments. These results often show the positive impact ITS can have on the environment but also their negative consequences: As ITS are intended to improve the fluidity of traffic flow and road safety, they can also have an unintentional consequence - induced traffic. This describes the increased demand from private vehicles resulting from improved traffic conditions. In this case the environmental damage increases.

The environmental assessments of experiments are provided in the different sections of the site according to the specific field. It should be noted that very few reports are available but t his can be explained by the fact that until recently these projects were only assessed in terms of their impact on traffic flows and road safety. Furthermore, environmental assessments are very difficult to carry out: The scope of the study is often very wide and the techniques for modelling pollutant and carbon dioxide emissions are still being perfected.