22 May 2010

Starting a rocket stove thermal mass heater

Its getting cold in Canberra. The fire place in our house is smokey and cold. The gas heating is too easy and expensive. Its time we learned how to build a rocket fire!

I discovered rocket fires last year when Permaculture Keith blogged about them. That lead to a couple of Youtube videos, which lead to meeting Erica and Ernie in Portland Oregon to see one in action.

Since that visit, Sunshine and I have been busy selling our house in NZ, moving to Australia, and having a baby. Now in a rental, its difficult to commit to a full build, but I've found a bit of time to study the method.

Basically, a rocket stove thermal mass heater is a super efficient wood fuel heater that can be built by just about anyone, using waste and/or easily collectible materials. To give you an idea, in Dunedin we used an efficient and certified wood burner that used about 4-6 cubic metres of wood per year. Erica and Ernie told us they use about 1-2 cubic metres in their rocket heater, and their house was less insulated than ours!

If you want to get a sense of what a full rocket stove thermal mass heater is, this is a great introductory video:

Here's the book that the video refers to.

And here's a really good illustration by Erica, of the critical design of the rocket stove. At that link are a series of photos documenting a full build, including the thermal mass heater.

Here's another photo documented installation with some adaptations to the standard design, by Michael Blaha.

And I started the Wikipedia article to see where it might go.

My attempts so far
So begins my attempts to study and learn this technique for heating. After the usual terrible time trying to source materials in Canberra, here's a series of videos of my first mock up.

Canberra is an incredibly difficult find out about anything online. The websites are crappy and the search results are worse. As a result, sourcing materials is frustrating. All we needed was some short lengths of steal pipe at varying diameters, a few steal drums of varying sizes, about 10 fire bricks, and 10 normal bricks. So I baled the family into the care and drove around looking for word of mouth. The main waste recycle facility was useless. We found private waste recycle yards that looked promising, but were all locked up with no one around. Everyone we spoke to directed us out to Fyshwick, the industrial hub of Canberra. There we found some materials, but all set at exorbitant prices :( It seems what useful materials is recycled, is pretty well stitched up by business. But we did manage to scrape together a few bricks and some guttering just to get this first mock up made.

The hunt for better materials continues...