My party approached an iron door in a dungeon and our rogue failed its Open Lock skill check. My duskblade took the opportunity to try and break the door. I have knowledge of hardness and hit points as outlined in the Dungeon Master's Guide, however some questions yet remain.
Can I add full power attack to damage?
How much extra damage will channeling shocking grasp add?
Also can chopping at lock or hinges speed up the process?
How to smash an object is covered here, and breaking hinges and locks is covered here.
There are a lot of fiddly rules for these tasks, and they are better read in the links than having them summarized in their entirety here. It's probably good to figure out which part of these rules are unclear then pose additional questions.
However, so you know, you can absolutely use the feat Power Attack when attacking objects (like doors). Further, that first linked section explains that the electricity damage dealt by the duskblade's shocking grasp spell is halved (before hardness) against the door.