Power on or shut down a VM (vSphere)
Simple PowerCLI example to connect to vCenter and power on or power off a single VM by name.
Script
# Connect to vCenter
Connect-VIServer -Server "vcsa01.lab.local"
# Power on a VM
Get-VM -Name "VM-NAME" | Start-VM
# Power off a VM (graceful)
Get-VM -Name "VM-NAME" | Stop-VM -Confirm:$false