A year ago, after we had just completed a prototype of a stove design we liked (it was literally made from an old metal trash can!) we decided to try adding a “pot skirt” to see how much it would improve our stove’s efficiency. We had read about these heat shields in other stoves before; the basic idea is to surround the pot on all sides with a thin metal shield that creates about an inch-gap for hot air to pass through. The pot skirt thus prevents heat from the stove from escaping to its surroundings, keeping it close to the walls of the pot and increasing the heating surface.

The idea sounded interesting, so we set to work building a prototype and testing it out! (My next post, “Frustrated by Frustums” will explain why our prototype is the shape it is-most pot skirts are actually just cylindrical.) The result was… WOW.

Adding the pot skirt cut down our rocket stove’s boiling time almost in half. The rocket stove itself was already able to boil water in maybe half the time it took an open flame, but with the pot skirt, we were boiling water at incredible speeds: up to a third of the time it takes to boil water on an open flame. Whatever we expected, I don’t think it was as drastic as this.

As great as it may sound though, our pot skirt idea still needs a lot of work. Adding that much material to our stove makes it more expensive and difficult to manufacture, not to mention clunky looking. Because it traps hot air, the skirt metal gets really hot too, posing a potential burn hazard to our customers. Our first prototype didn’t allow the cook to see the flame very well either (we fixed that issue by cutting out holes into the skirt).

Right now, we’re starting to explore new skirt designs, as well as some completely new concepts. One of the things we’d like to try is something similar to a “heat exchanger” which traps hot convective air at the bottom of the pot. The Jet Boil camping stove uses a mechanism like this. Such a design wouldn’t increase our heating surface area, but it will at least increase the concentration of hot air, which may be enough.

If you have any ideas about this engineering challenge, we’d love to hear them!

Coming up with a name is hard.  Really, really hard.  Especially in a world where URLs are so important but domain squatters have seemingly grabbed everything out there.

Over the course of a week, we spent over 10 hours brainstorming together working through concepts for our name.  We were coming up with a bunch of OK ideas, but nothing was feeling right.  And then, during the ride home from one such session, it just hit Jackie and Larissa: it’s all about the 3 brick stove.  The rest seemed quite obvious to the three of us:

About 3 billion people still cook on an open flame–often with their pots resting on three bricks or stones.  When we first saw these stoves, we immediately assumed it would be easy to create a better design because they are unsafe and very inefficient at transferring heat.  However their durability, ease of use, and minimal up-front cost make them tough competition.

Our team’s name is about having respect, understanding culture, and designing the best solution for our customers.  There’s a reason why these three-brick stoves have been around for thousands of years.  They are not perfect, but we have more to learn from them than most people might think.

We picked the name about a month ago.  I think we all are still quite pleased about the decision.  :-)