Power Notifications lets any Salesforce user to receive push notifications in their favorite browser.
A salesforce administrator can use profiles or permission sets to enable access to Power Notifications tab.
Let's take an example that you want all the users with Standard User profile to be able to access Power Notifications tab. Here is the step by step guide on how to enable the tab for Standard User profile.
1. Make Tab Visible
Go to Setup, in the Quick Find box type "Profiles" and click on "Profiles".
Select Standard User profile and click on Edit button.
Locate the "Custom Tab Settings" section on the page, under that section you will see "Power Notifications"
Set "Default Off" and click Save button. Once the settings are saved, Standard User profile users will be able to access Power Notifications tab and then can configure notification preferences.
2. Provide access to PowerNotifications page
Go to Setup -> Profiles -> Standard User profile
Click Visualforce Page Access
Click Edit and select powerpack.PowerNotifications page
Now users have Standard User profile should able to access Power Notifications tab.