Well Known and Active Forum Website User
Earlier this year I installed a 12V ceramic fan heater from Maplin Electronics in my Martello sidecar. This works very well in a 'hard top' chair but probably wouldn't be effective in an open sidecar. However, this month Maplins have a 12V 48W electric blanket on offer, code A75HT, normal price £24.99, but now only £9.99 until the end of September. This is probably the easiest way to keep your passenger warm and even a dynamo would cope with 48W if you don't ride with your lights on.