Hi I am Takeshi, CEO of su-re.co and firesmith!!
The coronavirus pandemic has made me stay at home more, even though I don't go out much. The central part of the house has no walls, so it's almost like being outside. I'm writing this blog while avoiding a lot of mosquito attacks. Because of this situation, I have spent more time at home, and I have started to do new outdoor activities. One of them is to make campfires of different designs. We have several trees at home, many fallen branches for firewood, and leftover scrap wood as residuals of our treehouses. I enjoy making rocket stoves and burning these.
The rocket stove is a stove that efficiently uses biomass fuel. The University of California, Berkeley, has a famous institute of this approach, where experts compete to see how efficiently wood can be burned. The rocket stove burns fuel more efficiently and produces less smoke, reducing indoor air pollution. It is a little known fact that the WHO estimates that about 4,000,000 people die annually from indoor air pollution. The death figure is about the same as Bali's population and more than the number of people dying from malaria and HIV combined. Using fuel more efficiently means using less firewood and reducing deforestation.
A simple stack of red bricks was enough to make this rocket stove. The stove is heated to create an updraft, which brings in fresh, oxygen-rich air from outside to make up for the air that is lost. This draft makes a roaring sound and burns the wood vigorously. An efficient flame is blue, so the flame shown in this video is not efficient, but I am playing with it to see a big flame rather than an efficient one ;-), which is why the video looks like this. When the combustion stabilises, the flame is no longer visible. It's inefficient to put more and more wood to see the flame. But isn't it magnificent to see the flames go up so high? There are very little smoke and very little wood left over, so if the wood is not from deforestation, it is a natural way of disposing of waste.
I have cooked fired rice and have roasted coffee beans with these rocket stoves ;-) It works!!.
The convection of air created by the updrafts makes the wood burn with great energy.
And because a rocket stove is so easy to make, the rocket stove is a better solution than biogas if you want to solve smoke pollution and energy problems to a large extent in a short time. However, biogas can deal with dung, which is another source of greenhouse gases and is a fundamental solution to not using firewood and getting free organic fertiliser. These multiple benefits are the reasons why we are working with biogas. Next year we are also thinking about carbon offsetting, utilising the properties of the gas. I'll talk about this another time.