Hybrid Stove Two
Lanny Henson, January 16, 2008
YouTube Video http://www.youtube.com/watch?v=6_7eRdIv_oU
My new stove the Hybrid Two has three phases. It cooks with wood and then switch to burn the charcoal produced by the wood and then shuts down to retain heat.
Instead of removing a center section like the first prototype, this stove telescopes, to switch from wood to the charcoal phase.
In the process the pot moves closer to the burner and a sleeve blocks excess airflow so that all the air is forced through the bottom of the burner, to burn the charcoal.
The stove system is made entirely from 4 pails and two cans.
There is a wind band and a top cap for the heat retaining mode.
In one test 500 grams of pallet oak cooked 4lb or 1.81 kilograms of dried pinto beans.
After the beans were soaked, and enough water was added to cook there was about 7 liters of volume and a little more than 7 kilograms of weight.
The wood burning phase brought the beans to a boil and continued cook about
15 to 20 min.
Then the charcoal phase simmered the pintos for about 30 to 45 min.
Then the heat retaining mode held the temp just below boiling for the second hour.
In the third hour the temp dropped to 85c/185f and down to 80c/175f. AT 3 hours the beans were soft and done.
There was no visible smoke after the wax burned off.
This is my second prototype and I am pleased with many of the elements of this design but it needs to be more user friendly.
For my next stove design I will keep the best elements of the Hybrid Stove but focus more on ease of use and simplicity of construction while trying to maintain efficiency. It may use a few more grams of fuel but I am thinking that the ease of use will out weigh that loss.
After all the cook has to like a stove, for a stove to be practical.
The burner was top lit.
The pot module helped to increases the draft and get the fire going.
3 min after the lighter was struck its ready for the pot to be inserted to start the cooking process
I heated the water first and then added the soaked beans to make 7 liters.
Near the end of the gasification phase I switched to the charcoal phase,
and when the simmering stopped I capped the stove to retain the heat.
The result 7 kilos of pintos cooked for 2.5 to 3 hours that is 52 servings, with 500 grams of wood
which gives a score is 9.1 grams of wood to cook a 134 gram servings of pintos.