Benefit Ledger · verified · Climate & Environment
Google Research’s Green Light, expanded publicly in 2023, uses Maps-derived models to suggest signal timing; Google reported up to 30 percent fewer stops and 10 percent lower intersection emissions in early tests covering tens of millions of monthly trips.
Current score
+0.07
Real but localized traffic intervention (tier 2). Attribution shared with city engineers. Developer-reported metrics (0.25). Realization is live intersections. Durability limited and reversible.
City engineers accept or reject recommendations on existing hardware. Scientific American documented mixed local uptake, including Seattle reverting at least one change and Manchester often ignoring suggestions that conflicted with bus or neighborhood priorities. Impact estimates are Google-modeled, not independently metered citywide.
Inferred stop-and-go patterns and proposed signal timing.
Model proposed timings; cities implemented a subset.
Attribution 0.5000 · Credit share 70% · Google
Green Light recommendations were implemented at intersections in multiple cities.
outcome · supported
The program cut intersection emissions by 10 percent everywhere it was tried.
outcome · disputed
primary sources
Google · developer announcement · 10 Oct 2023
independent sources
Scientific American · journalism · 1 Jun 2024
Secondary domains: Engineering
13 Sep 2026 · 0.00 → 0.07
Initial adjudicated seed score under methodology 0.1.