The Hot spot is a solid fuel burning gasifier stove. Observed the recent stove projects and the traditional cooking stoves around the world I realized that the efficiency itself is not only should be about the burning itself.
Efficiency-wise, here are many excellent stoves, but many of them immobile, ponderous, difficult to transport and not easy to assemble. On the other hand. That the indoor smoke is a vast problem cause respiratory-related diseases around the world. So the efficiency is not only about the pollution or fuel use, about health as well.
I designed a stove witch made of thin steel sheets by the cheapest metal working technologies cutting and pressing. It makes it cheap, light and easy to assemble like playing with paper sheets.
Insulation-wise, I used local soil (or sand) because these are excellent heat capacitors with good insulating abilities and the mass of the soil also provide stability for the construction, and not needed to be transported, manufactured.
The design is as simple as it can be. Not only because the price. This stove usable everywhere around the world in different environments from South America to Africa, India, or Siberia. It must be ease to use, ease to assemble and fit to any environment even in charity or trade application.
