It's no big secret that Google's Chrome browser is a bit of a battery hog. The native browsers on both Windows and macOS (Edge and Safari) are widely reported to outlast Google's offering. In its latest campaign, Microsoft is quantifying this difference: in a test of video playback Microsoft's latest browser lasted 7 hours and 22 minutes on a Surface Book system. Chrome lasted just 4 hours and 19 minutes.

Between these extremes were Firefox, at 5 hours and 9 minutes, and Opera in battery-saving mode, at 6 hours and 18 minutes.

Microsoft has gone a step beyond just measuring how long each system runs by measuring the power draw of the Wi-Fi, CPU, and GPU during a test workload that cycled through some common sites including Facebook, YouTube, Wikipedia, and Amazon. This task drew 2.1W in Edge, but pulled 2.8W in Chrome, 3.1W in Opera, and 3.2W in Firefox. This lower draw translates to the longer battery life.

The Windows 10 Anniversary update is making further changes to improve Edge's power efficiency. Some of these tweaks are surprisingly small—for example, changing how certain animations are performed in the toolbar to allow greater offloading to the GPU—whereas others are larger.

Flash content that is not deemed to be central to a page's content will become click-to-play, which is something that other browsers also do. Background tabs will also use fewer resources by making their JavaScript timers fire less frequently and by using coalescing to ensure that they all fire together and hence reduce the number of times that the processor must be woken up. This shouldn't interfere with listening to music or, say, checking for mail in a background tab, but it should reduce the overhead due to spurious animations and so on.

Microsoft is also making some networking changes in Edge and the Anniversary update to speed up the initial connection to a server and to allow larger data packets to be used sooner. Edge will also more aggressively re-request data that appears to be timing out. These changes mean that the Wi-Fi connection can be put into low power mode more aggressively.

Edge's rendering engine does a good job of showing pages, and aspects like the power consumption are certainly desirable for mobile users. But in spite of these changes, many of us will continue to use Chrome. Edge is currently deeply feature-deficient when compared to Chrome, Firefox, and Opera. The Anniversary update takes some important steps toward rectifying the problem, with pinned tabs and support for extensions. These types of steps help Edge move toward being a practical day-to-day browser.

For mobile users, at least, Edge will be well worth checking out. If Microsoft's figures are representative of normal Web usage—and they certainly reflect our own experiences—then there are enormous gains to be had from using Edge instead of Chrome or Firefox. With Edge going some way toward filling the feature gap and having a substantial lead in power efficiency, it's going to keep you browsing for much longer than the alternatives.