PS C:\> Get-UcsCmdletMeta -ClassId LsPower -Tree
LsServer (UcsServiceProfile) (Get, Add, Set, Remove)
|-LsPower (UcsServerPower) (Get, Set)
PS C:\>

$sp = Get-UcsOrg –Level root | Get-UcsServiceProfile –Name foobar –LimitScope | Set-UcsServerPower –State admin-up

Thanks,
- bhaskar