Not my car and I've just had time for a quick look at the problem...
The alternator seems to have gone - charge voltage is wandering about all the time and the battery went flat. It's a 98 Mondeo 1.8 diesel with a/c. I think the engine is an Endura-DE.
It looks as if the a/c compressor is installed on the end of the alternator(?) - two large pipes going into a thingummy on the none driven end of the alternator. Is there a way to replace the alternator without disturbing the a/c please?