Rocket Mass Heaters
Rocket mass heaters (RMH) are slow-release wood burning radiant heating systems that are very fuel efficient. Variations of RMH can also be extended for the functions of cooking, heating water, heating benches, floors and walls.
The by-products of combustion, such as smoke, soot, creosote compounds are sucked into the insulated tunnel of the unit. When designed correctly all the heat is retained in the mass of the structure and routed through vents so that by the time the exhaust reaches outside all the toxic gases have settled and the air is room temperature.
There are many ways to build DIY rocket mass heaters. Much more information on this and many other topics in sustainable living can be developed with your support.