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Traffic lights

Have you noticed that sometimes you have a green wave allowing you to easily cruise on in traffic, while sometimes you have to stop at every traffic light? The green wave that makes driving pleasant is not pure luck, but a sign of fine interplay of traffic light technologies. Read about how traffic lights contribute to smooth road traffic and how the lights change in practice.

There are approximately 2,200 traffic light junctions in Finland, of which Fintraffic manages about seven hundred. Traffic lights play an important role in smooth and safe traffic, especially on congested roads and challenging junctions. Even though traffic lights are a common sight on the streets, some people may not know how they work. 

Traffic lights improve traffic flow and safety

Traffic lights change with the help of a system based on vehicle identification. In addition, especially on more congested roads, traffic lights also have automatic programs to change the lights. For example, in large cities commuting traffic has been taken into account so that in the mornings more green light is shown to the flow of vehicles entering the city, while in the afternoon leaving the city is made easier.

When it comes to public transport, larger cities have created priority systems for public transport in the planning of traffic light systems. This means that the lights have a detector that allow them to take account of approaching public transport vehicles and let them pass through the lights smoothly. This saves time and reduces emissions when, for example, buses do not need to stand in the traffic lights unnecessarily and wait for the light to change. There is also a traffic light priority system for emergency vehicles, which speeds up the journey of emergency vehicles, while improving the safety of other road users.

Traffic lights even communicate directly with a vehicles

Traffic light systems will develop significantly in the future. Flexible systems are being developed in which traffic lights learn the traffic volumes at a junction and can automatically adapt their operation to the appropriate rhythm. 

Further opportunities will be provided by Cooperative Intelligent Transport Systems (C-ITS systems) in which traffic lights automatically communicate with roadside signs or even directly with vehicles. For example, the system may warn you about an approaching emergency vehicle or indicate what speed you should drive to get through the next junction without needing to wait unnecessarily.

Modern traffic light systems help to promote traffic flow in a new way, reducing emissions, facilitating anticipation and responding to situations in traffic, and improving traffic safety. Motorists benefit from advanced traffic light systems through savings in fuel costs – when traffic flows smoothly, the vehicles consume less fuel.