GreenCatch: green light for everyone


There are many advantages to traffic flowing smoothly through a city. Less stationary traffic results in a calmer traffic situation, less noise pollution, lower carbon emissions, and lower fuel consumption. Because traffic lights play a crucial role in realizing this, Technolution developed the GreenCatch app. This app helps all road users by giving them customized speed recommendations, so that the time they spend waiting at red lights is reduced.

The right speed for green

GreenCatch operates on a simple basic principle. The app knows when the next traffic light is going to go green, and provides speed advice to road users. If road users keep to the recommended speed, the next traffic light they encounter will be green. GreenCatch effectively creates a green wave for every road user.

For all forms of moving traffic

GreenCatch knows the status of every traffic light, including bicycle lane traffic lights and special lights for public transport. GreenCatch is therefore suited for all forms of moving traffic: bikes, cars, freight trucks, and public transport. Users can indicate the means of transportation they are using and the app will adjust its speed recommendation accordingly.

Safe advice

Of course GreenCath’s recommendations are always safe. The app will never recommend that users drive faster than the speed limit on the spot. Nor will it advise them to drive more slowly than the traffic situation warrants. GreenCatch stops giving recommendations as road users approach the next traffic light, to ensure that they don’t focus too much on the app instead of the traffic light itself.

WiFi-P and 4G

The Danish capital of Copenhagen is the first city where GreenCatch has been implemented. In Copenhagen, the GreenCatch app is available in two versions. The difference lies in the way in which it receives the traffic lights’ time-to-green and time-to-red data. The app’s WiFi-P version (ITS-G5) uses Bluetooth to contact a WiFi-P receptor in the car, and this in turn connects with transmitters along the roadside. This version is initially being tested with freight trucks.

The app’s 4G version receives traffic light data from a central server on the basis of the user’s GPS position. This back-end server collects data from roadside systems and passes them on to the GreenCatch app through the cloud and 4G. GreenCatch’s 4G version is suitable for all moving road users, from cyclists to truck drivers.



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