'Self-Regulating' Traffic Lights Reduce Waiting Time

Researchers in Europe are experimenting with a new kind of traffic light that better responds to traffic by monitoring the actual amount of cars on the road and estimating how long lights should stay green.

1 minute read

September 21, 2010, 9:00 AM PDT

By Nate Berg


"Stefan Lämmer at the Dresden University of Technology and Dirk Helbing of ETH Zurich made a computer model of Dresden's roads, in which the traffic streams flowed and merged not unlike water going through pipes. They then equipped the virtual traffic lights on those roads with sensors that monitored the local traffic flow. Using this input, each light calculated the expected number of immediately oncoming vehicles, and figured out how long it would have to stay green in order to let that traffic through."

The researchers found that these "self-regulating" traffic lights could reduce the amount of time spent waiting at traffic signals by 10%-30%.

Thursday, September 16, 2010 in Gizmag

Young Professional

I love the variety of courses, many practical, and all richly illustrated. They have inspired many ideas that I've applied in practice, and in my own teaching. Mary G., Urban and Environmental Planner

I love the variety of courses, many practical, and all richly illustrated. They have inspired many ideas that I've applied in practice, and in my own teaching.

Mary G., Urban and Environmental Planner

Get top-rated, practical training for planners

"Planetizen federal action tracker" logo superimposed over black and white image of US Capitol dome.

Planetizen Federal Action Tracker

A weekly monitor of how Trump’s orders and actions are impacting planners and planning in America.

September 23, 2026 - Zachary Whalen

Passengers board an Amtrak train under a cloudy sky.

Amtrak, CN end decades-long dispute with eight-year agreement

The new operating agreement establishes an updated framework for the companies to work together, including processes to resolve disputes.

September 18, 2026 - Mass Transit

An Airo train driving towards the camera on a track. There is a forest behind it.

Northwest rail fans eager for Sept. 30 debut of Amtrak’s Airo fleet

Get ready for that new train smell and more seats. But they won’t go faster or run more frequently on the Cascades route in Washington and Oregon.

September 22, 2026 - Washington State Standard

A sign in a field that reads "Save the goats, no data center"

This rural Oklahoma town doesn’t want a data center. It may not be able to stop the project

With the project outside city limits and little county oversight of unincorporated land, officials are considering measures to gain local control.

45 minutes ago - The Frontier

Two people in hi-vis vests install solar panels on a blue roof.

Trump administration unlawfully slashed $7 billion in clean energy grants, judge rules

The Environmental Protection Agency ended the Solar For All program, which provided the grants, after President Donald Trump’s inauguration.

September 28 - Inside Climate News

The largest wildlife overpass in North America stretching over the I-25. Both sides of the overpass, and the overpass itself, are covered in brown grass.

Record-breaking wildlife overpass in Colorado brings 91% reduction in animal collisions

Prior to the overpass, vehicles were hitting one deer per day on Colorado’s Interstate 25.

September 28 - CBS Colorado

FREE Course: Walkable City 1: Why Walkability?

After describing his path towards focusing on walkability as the essence of good planning, Jeff Speck marches through his five principal reasons for making more walkable places.

Reinventing Malls: Planning Alchemy—Turning Gray Fields Into Gold

The course focuses on the opportunities and imperatives that shape reinvention of mall sites.

Senior Planner

City of Thousand Oaks

Community Development Director

City of Wisconsin Rapids

Professor of Urban Planning

Harvard University Graduate School of Design