Google's Green Light uses AI to cut intersection traffic emissions

Google Research launched Green Light, an AI tool using Google Maps data to optimize traffic signals, operating across 70 intersections in 12 cities including Bangalore. The technology shows up to a 10% emissions reduction at intersections, offering Indian cities a low-cost urban decarbonization option.

Google Research's Green Light initiative uses AI to analyze driving data from Google Maps, modelling traffic patterns and recommending optimized traffic signal plans that city engineers can implement within roughly five minutes using existing infrastructure. Urban intersection emissions can reach 29 times higher than open roads, with about half stemming from vehicle stop-and-go. Preliminary data shows up to a 30% reduction in stops and a 10% decrease in emissions at intersections, potentially benefiting up to 30 million car rides per month.

Cities, municipal traffic engineers and urban residents are directly affected. Green Light is operational across 70 intersections in 12 cities, spanning Haifa, Rio de Janeiro and Bangalore, and has proven successful in Seattle and Hamburg. Previously, engineers relied on expensive sensors or time-consuming manual vehicle counts that often left intersections with outdated configurations. By coordinating across neighbouring intersections to create sequences of green lights, the tool enhances traffic flow and reduces stop-and-go emissions.

Indian cities and municipal authorities, with Bangalore already participating, should monitor Green Light as a low-cost option to cut urban transport emissions using existing signal infrastructure. City officials are encouraged to join the waiting list to participate. Indian urban-planning bodies can assess the documented potential for up to 30% fewer stops and 10% lower intersection emissions, particularly valuable in areas with limited access to advanced traffic-management technology, as the initiative expands to additional cities.

Key figure — Emissions impact: up to 10% decrease and 30% fewer stops at intersections