TEAM 14: MARGARET FRAZIER, SOPHIE GOLDBERG, ABBY HUGHES, SARA MAGDALENA, ALDA ZENELI
Our Team
Introduction
In ENGS 21: Introduction to Engineering, our team of Dartmouth undergraduates worked to design, test, and develop a product to combat the issue of indoor air pollution and smoke inhalation from wood-fired stoves. Our all-female group wanted to solve a problem that largely impacted women, and ultimately chose to focus on innovating for rural communities with access to water and wood-fired stoves, but not electricity.
Problem Statement / Magnitude
Users/Purchasers
As introduced, the Sano Stove's intended user base is women and children spending extended amounts of time in close proximity to indoor wood-burning stoves. We recognize that users may not have the resources available to them to purchase alternative clean cooking technologies, such as the Sano Stove.
As such, we are relying on non-governmental organizations (NGOs) to purchase and help facilitate the widespread distribution and ethical implementation of the Sano Stove in targeted communities. Among potential purchasers we have identified are Build Health International, Burn Design Lab, and the Clean Cooking Alliance.
As a team, we have taken advantage of our international connections, surveying users in Guatemala and Albania, and meeting with engineers working for Burn Design Lab (BDL) in Ghana. We recognize the barriers inherent in remote product development, and worked to remedy this by keeping user interests and firsthand experiences at the forefront of all design and planning.
State of the Art
Specifications
Prototypes
Our team went through many design iterations, in terms of both sketching and prototype development in the Machine Shop. This work allowed us to gain familiarity with a lot of diverse equipment, including the plasma cutter, welding shop, knee mill, and sand blaster, primarily.
Many of our pimary designs included carbon filtering systems and mechanical fans, as a reaction to the smoke outputted by the wood fire. With our final prototype, our team decided to shift to a more preventative solution, employing the use of the secondary burn, or clean burn method in the Sano Stove.
The secondary burn method includes primary air entrance slits at the base of the Sano Stove, accelerating initial combustion. As heat and smoke work their way up the chamber, the secondary air entrance valves on either side of the conical device introduce new fresh air. This preheated air is then reignited at the site of the hollow steel tubing surrounding the circumference of the top of the device. In the end, the secondary burn mechanism increases efficiency, provides a more complete combustion, and significantly reduces smoke output from the Sano Stove.
Testing and User Feedback
To test the specifications of the SanoStove, we conducted 3 main tests. The first was testing the Air Quality Index of air and smoke produced by a normal wood fire (comparable to what our users currently cook over), and by the SanoStove. As you can see below, the smoke produced from a normal wood fire was significantly higher than the smoke proudced by the SanoStove, even over a long period of time. Our stove successfully kept smoke out of the air, and kept AQI levels in a category that would be safe for our users.
We also tested the amount of time required to boil 3 quarts of water on the SanoStove compared to other cooking methods. Compared to a wood fire, the SanoStove takes about 2 minutes longer. This is not a significant loss of time, but can likely be attributed to a few different causes, all of which are easily solved with tweaks to the prototype or its use. First, we could make the pot holder shorter which would increase the heat transfer. Second, we could insulate the stove to make sure that no heat is lost from the sides of the device. Third, by using it inside and minimizing wind, less heat would be lost.
Finally, we conducted a series of user tests on both local users and potential users here. This gave us an idea of how easy the stove would be to use, and helped us understand how best to improve future iterations of the prototype.
Ethics and Sustainability
Business Plan and Economics
