The Chromebook Battery Saver is taking shape to allow better battery life on the go

Back in March of this year, we posted about a new Battery Saver on the way to ChromeOS. While there is an Energy Saver for the Chrome browser already out in there in the world, this OS-level battery saver would obviously be meant for Chromebook users: not those on MacOS, Windows, or Linux. While the Chrome browser’s Energy Saver definitely helps ChromeOS users, too, these new OS-level changes will go far beyond browser-based tweaks.

Finally, CPU throttling for Chromebooks

Thanks to some new commits over the past few weeks regarding Battery Saver for ChromeOS, I can finally confirm that Chromebooks will get a toggle switch down the road to allow for this new feature. And I can also confirm that this will do far more than simply turn down your brightness level on your display; though it will do that, too.

Instead, we’re finally seeing CPU governors being added that will allow the user to enable or remove throttling on the actual processor inside the Chromebook. As we’ve had on Windows for years at this point, ChromeOS will finally be able to ramp things down a bit to conserve battery when you are on the go.

According to the commit, it looks like Battery Saver will operate in a few different ways. First, if the device utilizes Intel’s EPP (energy performance preference), ChromeOS will simply move to a balanced power state like we see on many Windows devices. If that isn’t an option, a CPUfreq governor will be used to push performance to a conservative setting. Finally, if the device uses a big/little core arrangement, energy saver will offline the small cores and if big/little isn’t present, half of the available cores will be turned off.

We’ve been able to get this new feature enabled in the Canary Channel and we’re seeing about 15% CPU power reduction simply based on a few benchmarks. That number could definitely change, but I’d wager somewhere around 15-25% would be the sweet spot for this throttling if – as it seems is the case – Google is going after a conservative approach to power saving versus an aggressive one.

What to expect and why this is a great thing

I’d expect this will be a setting that will eventually be a default behavior for Chromebooks when pulled off of the charger. Hopefully a few settings will be available down the road like default brightness levels and maybe even a balanced and extreme power saver mode. For now, as long as the battery saver mode kicks in when unplugged and can simply be toggled off if full power is desired by the user, this will be a huge step in the right direction.

When I imagine how this will all help, I think of Chromebooks with hideous battery life like the Samsung Galaxy Chromebook that had plenty of power to offload. Had this been a feature when that device came out, perhaps reviews would have been a bit kinder. And with the current state of Chromebooks where we have lots of devices with oodles of power to spare for general workflows, this throttling only makes that much more sense.

Many times these days a Chromebook will come to our office and have the latest specs and be lightning fast at everything I tend to do; but that same thing can be said of Chromebooks from a few years ago, too. From a general hardware perspective at this stage of the Chromebook story, we have plenty of headroom in the performance category, so having the ability to quickly pull back those reins a bit will be a huge help to the vast majority of users that don’t really need all that power and would benefit far more from extended battery life.

And I feel like I also have to point out the difference in this method versus the AMD version of this we reported on a few years back. The Ryzen 3500 devices were notorious for automatically throttling about 40% performance when unplugged to juice up battery life numbers. While this is similar to what we’re talking about with the ChromeOS Battery Saver feature, the key difference is in user control. Being able to decide that you don’t want that extra battery life is something every Chromebook user should be able to choose and not have it forced upon them. And this is precisely what we’re seeing with this new feature. I’m definitely excited for this to roll out in the coming weeks, and as we find out more about it, we’ll be sure to report.