I noticed from a recent survey of the keywords used to access my site, that 45% of you were typing in “wood stove Stirling fan” . So, in order to give you what you want, here is the homepage of the Canadian built Free Breeze Fan. The idea is simple – a low tech, Stirling engine, optimized for the sort of temperatures that would be found on the hot plate of a stove (250 to 350 C) which drives a slow moving air circulation fan. This helps to circulate the warmed air around the room and give a greater degree of comfort.
Stirling fans were traditionally used to generate a cool breeze in tropical climates, and I believe that one features in the film “Casablanca”. They were often paraffin (kerosene) fueled and generally blew paraffin fumes around the room! A modern paraffin fired hot-air fan was being manufactured in Pakistan until only 2 years ago. One of the early experimental Stirling engines produced by Philips drove a high speed fan. It was never produced in volume.
Small Stirling engines can be easily built, and will produce up to 10W of power in a package about the size of a CD Rom drive and produce a few watts of electricity. A small Stirling will run on solar power using an 18″ parabolic reflector, and I witnessed this happen in England on January 1st this year! A simple variation would allow one to be fired from a camp fire or cooking stove. This could the be used to charge up batteries of emergency communications equipment, or navigation gear. To the outward bound adventurer, a device which produces warmth and emergency power and could be used to cook on, would be of great benefit. Especially if it runs on twigs!