shutdown by regular user

[william drescher]

How can a non-privileged user initiate a shutdown.

There is one person with an administrative account and sudo 
privleges.  There are 3 others with no account.  Frequently, in 
case of emergency shutdown the admin user is not available.

I would like to set up a regular user but make it possible for 
that user to run shutdown. In Unix I would use asroot, but Ubuntu 
14.4 LTS does not have that.

How can I do this.

-bill