I did some pretty scientific research this week....literally. The results I got were pretty surprising to me so I figured I would share them here for other's knowledge in case any newbies wanted to try using an alcohol stove on their next campout. The three stoves tested were all made by me.
1. Pepsi can stove (3rd picture down on this page.)
http://zenstoves.net/BasicTopBurner.htm The only thing I did different (and this may have been a negative effect, or not) was I used an Arnold Palmer ice tea can instead of a pop can which is a little bigger in diameter.
2. Min Zen chimney/sideburner stove made from a smaller coors banquet beer can (4th picture down on this page)
http://zenstoves.net/ChimneyStove.htm3. My own variation of the chimney stove using a 4.5 oz steel olive can.
I am going to keep this as short as possible. I used a syringe to measure 3/4 oz HEET for each test. I used my smart phone timer to time each stove. I also tested each stove from start to time to boil with 73 F tap water. I used a pot support to support the steel pot approximately 1-1.5" above the stove top.
I have been personally using my Top burner (Arnold palmer) stove since last spring and it has done the job. I recently got on a quest for efficiency so I can take less fuel. Thus these tests.
Time to boil was not surprising. All 3 stoves must be putting out similar BTUs as they all boiled water right around the 7 minute mark with a full rolling boil a little over 8 minutes. This was uncovered. When I camp I put the lid on and achieve cooking temps even for Ramen Noodles without bringing the pot to a full boil so you could save fuel in the real world by using less.
Here is the surprising results. I tested the Arnold can and the Coors can earlier this week and didn't take any pics so I apologize. I tested the Coors chimney stove and my variation, Olive can chimney stove yesterday and I will post the pics as well as the different measurements between the 2 cans. Since the coors can and olive can are identical stoves with the only difference being can dimensions and intake placement, I will post measurements of those 2 stoves. With the exception of the arnold can stove using a bigger can than the pepsi can, the stove is otherwise made exactly to plan using templates from the zen stove site.
Arnold stove (or pepsi can or low pressure top burner stove)3/4 ounce fuel burn time- 7:40
Coors can chimney stove3/4 ounce fuel burn time- 9:45
Olive can chimney stove3/4 ounce fuel burn time- 11:20
Those results floored me. I was expecting the top burner stove to be the most efficient since it used small jets instead of one large opening. What made the Olive can stove so dang fuel efficient? Heck i don't know. All I can post is spec differences in the cans. That has to be where the efficiency difference comes in.
Coors canHeight- 1 1/2"
Width across-2 7/16"
top orifice- 15/16"
intakes- 8 evenly spaced, 1/4" diameter, 7/16" from top orifice
Bottom of stove- inverted concave (bottom of beer can lol)
Olive can Height- 1 7/8"
width across- 3 5/8"
Top orifice- 15/16"
intakes- 8 evenly spaced, 1/4" diameter, 5/8" from top orifice
Bottom of stove- flat
The stove height was measured from the bottom (where it sat on the ground) to the top of the orifice (chimney). As mentioned the olive can was steel. The results don't lie. I tested both these stoves several times over and got similar results every time.
