Microsoft claims that Windows 10's new power-throttling feature will boost battery life by about 11 percent, though you'll need a modern laptop to take advantage of it.
Microsoft introduced the new feature to slow down background apps in January, as a trial feature for a subset of users running Insider versions of Windows 10. While power-throttling is still limited to Insiders, the recent Build 16176 made it more widely available.
There's one catch: Power throttling leverages Intel's Speed Shift technology, which debuted in Intel's sixth-generation (Skylake) Core chips that began shipping in late 2015. Current laptops with AMD processors won't be able to take advantage of the power savings, a Microsoft representative confirmed, though that could change in the near future: The representative added that the company's "working on expanding support to other processors as well over the next few months."