The Wiki link does expand on the possibilities of steam power making a return but the general opinion seems to be that it is not going to happen because of elfin-safety amongst other problems not least being the vested interests of the oil companies and car manufacturers and the decline in knowledge of steam technology.
This book
"From Stonehenge to Samarkand" By Brian M. Fagan
Mentions that your Mr Byron was meant to be given a lift in a Charcoal Powered RR but that this failed to materialise.
That and the obit that confirms a similar vehicle was in use just after WWII are the only references I can find to charcoal powered Rolls Royce.
I have to conclude that steam was the driving force as charcoal on its own will not make anything move (unless BM sits on the BBQ by mistake). Most steam cars appear to have used Gas or Kerosene to heat the water but any source of heat would do I guess and two separate mentions of charcoal power, one in 1933 and the other in 1946, either in an area where petrol might be hard to come by or in the case of the second where petrol was in very short supply because of the war it would make some sense.
I wonder if they were one and the same vehicle?
