Chrome introduces Energy Saver mode for PWAs and tabs with heavy web workers

Tech · 3 min read

Chrome’s Energy Saver mode targets background pages, persistent web workers, and PWAs that consume disproportionate CPU or GPU cycles. The mode selectively reduces worker frequency, defers nonessential rendering, and issues developer console warnings when thresholds are exceeded.

For PWAs installed on laptops or tablets, Chrome exposes a manifest flag to declare background-critical tasks (like music playback or file syncing) so they remain exempt. The browser also ships a DevTools panel that profiles energy consumption and suggests code-level optimizations.

Designers and engineers can use these tools to build web apps that are more battery-friendly and to surface graceful degradation states for users on low power. Google says the feature will roll out gradually with telemetry-driven tuning to avoid false positives.