With this FREE software, you can easily unlock your Power Plans for changing.
Simply run this utility to Enable/Disable or check the setting (Check).
Reboot after changing settings.
Microsoft Surface devices come with a predefined power plan called Balanced. The Balanced power plan is limited. It does not allow for much configuration. Unlock Power Plans using this utility. After restarting your computer, you should be able to access all power plans options including Power saver, Balanced, and High performance.