Add-SPShellAdmin
http://technet.microsoft.com/en-us/library/ff607596.aspx

Follow the steps below
1. Go to Start menu
2. Right click on PowerShell and select run as administrator option
3. This will open up PowerShell utility
4. Now type in add-PSSnapin Microsoft.SharePoint.PowerShell and hit Enter
5. Type in any other PowerShell command and Enter

I have recently cloned one of my Sharepoint 2010 VM. I tried to use Rename-SPServer options. However, when I try to run these commands in PowerShell, it gives me an error saying, “The local farm is not accessible. Cmdlets with FeatureDependencyId are not registered.” .Search on internet and your blog entry provided me with two possible solutions/remedies. (1) To ensure that the logged in user has Sharepoint_Shell_Access role membership in Sharepoint_Config database, and (2) To run the Management Shell as Administrator. Both the scenarios are true in my case. Can you suggest any other alternative solution?

Thanks in anticipation.