Hello Shibbu, i have an iPad 2 RevA, if your iPad is jailbroken, you are able to connect Some Low Power consuming USB flash drives to the iPad with the camera connection kit, you need iFile , Cxmb.
With those two jailbreaking apps, you can play nearly any video format
Directly from the flash drive ,i used to do that when i was on iOS 6.1.2 , watching The Walking Dead Seasons without even consuming any Space from the iPad.
And no, it's not that power consuming at all
In my case with my iPad 2 RevA, i used 2 USB flash drives (Sandisk 8gb,16gb). , sandisk seem to work very good with me.
I also go one 8gb Kingston drive to work.
Hope this helped & have fun