Introducing Power Throttling – The Battery-saving tech in Win 10 'Redstone 3'

Microsoft is working to add a new battery-saving feature to Windows 10 'Redstone 3', and it has begun testing it on machines with Intel sixth-generation and beyond Core processors. Microsoft rolled out its second "Redstone 3" test build for PCs on April 14. On April 18, officials went public with one of the under-the-cover features in that build: PowerThrottling.

Most people running Windows like having multiple apps running at the same time – and often, what’s running in the background can drain your battery. With “Power Throttling”, when background work is running, Windows places the CPU in its most energy efficient operating modes – work gets done, but the minimal possible battery is spent on that work.

Power Throttling (a temporary, not final, name for this feature) is in the Insider Preview build 16176 for Fast Ring PC testers. Microsoft executives said in a blog post that this feature uses "modern silicon capabilities" to run background tasks in a more power-efficient manner.

Microsoft officials first talked up intentions to provide this kind of battery-saving feature in January, when the company was testing the Windows 10 Creators Update, in Build 15002 of the Creators Update. Microsoft officials said they were experimenting with power throttling with some, but not all, testers. In early experiments, Microsoft executives said Power Throttling showed up to an 11-percent savings in CPU power consumption for "some of the most strenuous cases."

Since then, Microsoft has continued working on this feature, which officials said should "help many of you see a nice boost in battery life."

How does it work?

To give great performance to the apps you’re using, while at the same time power throttling background work, Microsoft built a sophisticated detection system into Windows. The OS identifies work that is important to you (apps in the foreground, apps playing music, as well as other categories of important work the system infer from the demands of running apps and the apps the user interacts with).

While this detection works well for most apps, if you happen to notice an app that is negatively impacted by Power Throttling, you can still work around it by:

-- Controlling power throttling system-wide, using the Power Slider.

-- Opt individual apps out from Power Throttling.

-- Alternatively provide feedback to Microsoft.

The blog post noted that Power Throttling currently only works with machines with Intel's Speed Shift technology, which is in Intel's sixth generation and beyond Skylake/Kaby Lake Core processors. Microsoft is working to support other processors with Power Throttling "over the next few months."

Power Throttling is designed to work with apps out of the box, Microsoft officials said, but developers can and may do some fine tuning over power Throttling to provide additional power savings with some new programming interfaces that Microsoft will provide in upcoming test builds.