I just happen to have a need to shut down my computer on its own at time I specify.
Is there any method to do so ?

That is not hard to do.

Goto desktop, right click,
New --> Shortcut -
Then paste following in it :

Code:

%windir%\system32\SHUTDOWN.exe -s -t 01

Now goto :
Program --> Accessories --> System Tools --> Scheduled Tasks
There add new task, give program to execute as the one we have created on desktop.