Is there a way to only require password when the computer is NOT plugged in?

Think about this for a second:
I only have the computer plugged in when in the house.
I only need a password when not in the house.

Is there a way to make it so that it only requires password to wake from screensaver or sleep when it runs of battery and not power? I know you can do this in windows 7 but I don't know about OSX.