One of the members of our motorhome club had the alternator fail at the
end of his holiday, just as he was setting off for home. He had to be at
work on the Monday, he was at the top end of Scotland, and couldn't hang
about. He tied his little Honda genny onto the roof platform, and fed
the mains voltage into one of his chargers. Linked the habitation
circuit fed from that charger to the vehicle battery via a long length
of TV coax. It worked fine, got him home. Several times he forgot to
disconnect whilst starting and strangely the TV cable didn't catch fire.

Bill