Image credit: Ecofilms Australia
If you like this ingenious low-work chicken tunnel garden system, then you'll most likely dig this footage from the same folks of a DIY water heater using rocket stove principles. Burning scraps of wood and tree prunings efficiently, this low tech design provides on-demand hot water with low emissions using basic craftsmanship and reclaimed materials.
I've posted before on the incredible efficiency of rocket stove heaters, but it's not just the amount of fuel they use that makes them remarkable—it's the type of fuel. As this clip from Geoff Lawton's Urban Permaculture DVD shows, rocket stoves work best on thin bits of wood, which makes them ideal for utilizing scrap wood waste and/or tree prunings and coppiced wood.
There are, of course, many reasons to be wary of burning wood for heat. But designs that burn much less of it, produce fewer emissions, and are selective about the type of wood they burn have got to go a long way toward answering these concerns. Right?