This is another one of my designs and is called the volcano stove, it is based on the principals that larger the stove flame/pot ratio the more efficient the stove/pot system is, (this is shown in my pot size/efficiency posting http://tonysbushwalking.wordpress.com/2010/08/20/50/)
And that slower heating is more efficient that fast boiling (fast boiling and efficiency with stoves is a myth that manufactures have perpetuated to sell stoves).
The cone top is to allow better air entrainment into the flame. The lip around the outside is for priming. The pin in the middle has the function of blocking the middle hole as well as transferring heat to the alcohol to aid vaporization and different size and mass pins can be used to adjust the flame strength. By this method I was able to tune the stove to improve its efficiency.
The stove is still in the development or tuning stage and has shown very promising results. I have had efficiency figures of 70%. The stove as pictured weighs in at 6 grams 0.21 oz). the pictured stove holds 25 mls the volcano can be made to hold larger alcohol volumes.
The volcano is made from the bases of two Red Bull cans with the top cone made by pressing between a specially made die. 8 x 1.3 mm hole are drilled in the top for jets and a 5 mm hole in the center for filling. The pin is machined from 6.35 mm aluninium bar. The bottom has been flattened out to allow for more volume.
The stove so far has only been tested on small diameter pots and has shown very good efficiency it also works very well with a JetBoil PCS pot that I modified. All of the small pot test have used less than 11.7g/80C (0.5 US fl oz/80C). I have not done large pot test yet but I expect some good results especially with the 1.5liter JetBoil GCS pot.
In the tests 0.5 liters of water was heated from between 20-25C to 95C and results extrapolated to get g/80C.
The best test result so far the volcano stove used 9.3 grams of denatured alcohol to heat 0.5 liters of water 80C and took 12 minutes. 9.3 grams = 11.77 mls = 0.4 US fluid ounces, in this test I used my modified 1liter JetBoil PCS pot. Of that 9.3 grams 0.55 grams (0.7mls) was used in priming.
Future developments will add a pot stand but this stove will work under most other pot stands.