To schedule automatic client shutdown create a new group policy or edit an existing group policy
Start editing the policy and navigate to: Computer Configuration > Preferences > Control Panel Settings >Scheduled Task
Right click on ‘Scheduled Tasks’ and select ‘New’ > ‘Scheduled Task (At least Windows 7)’
On the General tab give the task a name. Use the account ‘NT AUTHORITY\System’ to run the task, and run the task whether the user is logged on or not.
On the Triggers tab create a new trigger setting required frequency and times.
On the Actions tab create a new action. Browse to the shutdown.exe and add the arguments /f /s /t 60
Add conditions if you want to avoid shutting down a computer while it’s still in use by a user.