unless the device is actively looking for other devices, i dont think the bluetooth radio is sending data. and even if it gets a message to make itself known, it will only reply if it set to visible.

beyond that i dont think bluetooth do much unless one is actively using the connection.

and wifi is much the same.

yes, having these radios turned on while not being used, can create more drain then having them turned of. but i would guess that its very much like having a cpu on idle. that is, the wattage used should be in the 0.something range...