Stoves and sopes

Nordica MacCarty podcast picture.


In part one, Nordica MacCarty, a faculty member in the Humanitarian Engineering Program at Oregon State, talks about improving the lives of women and children in the developing world through cleaner-burning cook stove technology. Traditional open-fire methods use fuel inefficiently, increasing the physical burden of household work and creating deadly indoor air pollution. 

In part two, we’ll follow an unlikely journey taken by Chinweike Eseonu, an Oregon State engineering assistant professor from Nigeria, along with three women from the tiny town of Monroe, Oregon, Spanish instructor Loren Chavarria, and three determined engineering students, and all made possible by some tasty Mexican food. 

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Season 2
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KEITH HAUTALA: Hey there, podcast listeners! This week’s episode of Engineering Out Loud is all about cooking. So, if you’re hungry, you might want to grab a snack before settling in. That’s coming right up.

[MUSIC: The Ether Bunny, Eyes Closed Audio, used with permissions of a Creative Commons Attribution License]

NARRATOR: From the College of Engineering at Oregon State University, this is Engineering Out Loud.

HAUTALA: This week on Engineering Out Loud, we present Stoves and Sopes, two stories about how engineering research is changing the way people cook. I’m Keith Hautala.

Later on in the program, we’ll be joined by Steve Frandzel with a story about some students who have formed a partnership with a group of women in small-town Oregon to help their start-up Mexican food business.

But first, we’re going to talk with Nordica MacCarty, a faculty member in the Humanitarian Engineering Program here at Oregon State, about something that most of us probably take for granted: the kitchen stove. Whenever we want to prepare a meal, or even a quick snack, we can just turn a knob and, like magic, an electric burner lights up — or a clean, blue flame,

[gas burner lighting]

if you’re cooking with gas. You might be surprised to learn that, for nearly half of the residents of Planet Earth, this kind of luxury simply doesn’t exist.

[MUSIC: Firefly, Poddington Bear, used with permission of a Creative Commons Attribution-Noncommercial License]

NORDICA MACCARTY: About 40 percent of the world's population is currently cooking with biomass to prepare their meals and heat their water and heat their homes. And this is primarily done inside. And so, you can imagine, if you've ever sat around a campfire, you know that biomass fires produce a lot of smoke. And so, being in the same time and confined space that cooking is happening, women and children are suffering severe health effects because of this necessary practice.

HAUTALA: As it turns out, indoor air pollution is actually a huge problem in the developing world, where smoke inhalation and related illnesses are among the leading killers of women and children, accounting for about 4 million premature deaths each year.

MACCARTY: To put that in relative terms, that's like the population of Los Angeles dying every year simply because they're cooking their meals to feed their families.

HAUTALA: Before we get too far, we should probably get the introductions out of the way.

MACCARTY: I'm Nordica MacCarty, assistant professor of mechanical engineering.

HAUTALA: So Nordica has been interested in cookstoves since she was an undergraduate in Iowa, way back in the 1990s. As an idealistic young college student, she was looking for a way to use engineering to make a positive impact for humanity. So, she started talking to her professor of fluid dynamics, who just happened to be one of the first people to look at cookstoves for the developing world. He suggested she head out to Oregon to volunteer with Aprovecho Research Center, a nonprofit group that was working on stove design.

[MUSIC: Firefly, Poddington Bear, used with permission of a Creative Commons Attribution-Noncommercial License]

MACCARTY: And so I agreed and I came out to volunteer for the summer,

[birds chirping, campfire crackling]

spending two months living in my tent and testing cookstoves and looking at various parametric variations of cookstoves: height and diameter and different sizes and doing testing to see which geometrical designs were more efficient, so that was kind of the start of what became a lifelong career in biomass cookstoves.

HAUTALA: Over the past couple of decades Oregon has come to be at the nexus of an international biomass cookstove movement. But it was really that impulse Nordica had as an undergrad — to do some good in the world — that led her to make her career here.

MACCARTY: It's really the Humanitarian Engineering Program at Oregon State that attracted me to come here.

[MUSIC: Firefly, Poddington Bear, used with permission of a Creative Commons Attribution-Noncommercial License]

I really believe in using engineering to benefit low-resource populations. And there's kind of a rule of thumb that Paul Pollack, who's the author of a book called Out of Poverty — it's an often-cited quote — he says that 90 percent of engineering design is aimed at only 10 percent of the population. So, in the Humanitarian Engineering Program we try to address the needs of the rest of that 90 percent, typically in low-resource communities like displaced person camps, rural developing communities, and less advantaged populations here in the U.S. as well, like tribal communities or alter-abled people who don't generally benefit from typical engineering design. And we do that through an interdisciplinary approach, which we like to think of "engineering in context," where in addition to a really heavy technical focus that engineers are so good at, where we can really address a technical problem, we also look at it in the context of its larger social, economic, environmental — the "Big Picture" — because we know that you can't just design a cookstove or a technology that works great in the lab and then go put in a home and expect it to have the impact that you want it to.

HAUTALA: Looking at the “Big Picture” for cookstoves, it isn’t just a simple health issue. It’s also a major gender-equity issue. In much of the developing world — and much more so than in advanced industrial countries — women and children perform a disproportionate amount of household labor, like cooking.

[MUSIC: Firefly, Poddington Bear, used with permission of a Creative Commons Attribution-Noncommercial License]

MACCARTY: They're also the ones who are primarily responsible for collecting the fuel wood. And so when they're using inefficient practices like traditional open fires for cooking, they spend a lot more time collecting fuel wood. So a typical woman will spend about two to four hours round-trip to go collect fuel wood and carry that back, often in very heavy loads.

And unfortunately in some regions, the forests are retreating around communities, and so this walk is getting longer and longer. And in some cases where there is conflict, then leaving the safety of places like displaced person or refugee camps is extremely dangerous for women, and they're often at a risk of being attacked or hurt in some way when they leave the safety of the community to go and get the firewood. And so it's a significant gender issue in that way.

HAUTALA: From a pure technology vantage point, the solution is pretty straightforward. The problem with traditional open-fire cooking is incomplete combustion: Not enough air gets to the fire, and it doesn’t get hot enough, so instead of a clean flame, it produces a bunch of smoke and carbon monoxide.

MACCARTY: If you're trying to cook over a campfire and you've got maybe three stones underneath the pot: Where you're trying to cook in that way, the flames are going every which direction, the wind is coming in and blowing the flames away from the pot. There's not good mixing or good insulated space where all this combustion can occur efficiently. So, engineers can provide small, inexpensive technologies that burn the fuel more efficiently and combust it more cleanly. So these small devices work to provide an insulated combustion chamber where the fuel is mixed with the air and the smoke in a small confined space so it stays hot and burns up these emissions more completely before they exit, and it also provides a way to transfer the heat more effectively into the cooking vessel through engineered gaps and stove body designs that force that heat more closely to the bottom and sides of the pot, so that the heat isn't wasted.

HAUTALA: So, if you’re at all like me, I know what you’re probably thinking right now: If these technologies are so simple and inexpensive, why aren’t they in use everywhere already? I mean, it’s 2017. We’re talking about fire.

MACCARTY: You're trying to market these devices to people who don't have any disposable income. Families live on two dollars a day, and most of that money goes to their food, as it should. And so trying to sell technologies to customers who have a free alternative — so the three-stone fire is free, they don't need to pay for it in any way. And so trying to set up a market-based approach to selling these stoves is very challenging. Another major challenge is designing something that people actually want to use. So the three-stone fire has been the tradition for thousands and thousands of years, and it's flexible and it's convenient. You can run it at high fire power, you can run it at low fire power, it can fit any pot you want to use. Whereas these cookstoves are typically designed to operate most efficiently within a narrow range of fire power or a certain type of pot. So you're asking people to change their behavior and often times their cooking styles to accommodate this technology.

HAUTALA: That’s where the Big Picture comes in again. Engineers have an important role to play in figuring out how to adapt cleaner burning stove technologies to meet the needs of local communities, but figuring out how to market those technologies and make them accessible and, perhaps more important, desirable to end-users isn’t a problem that can engineering can solve on its own. 

MACCARTY: We are pretty heavily partnered with an organization called Stove Team International. And they have a stove design that's called the Ecocina. Their business model is to set up factories around Latin America and help the factories get started, often with funding from Rotary organizations, and then hope that these factories become self-sustaining businesses. And so they have I think it's now six factories across Latin America that manufacture industry of the cookstoves that they designed. This summer I hosted a faculty-led study abroad class with Stove Team when we took 11 students from mechanical engineering and public policy and economics down to Guatemala. And we looked at cookstoves from an interdisciplinary perspective and evaluated their performance when we were working with local cooks doing controlled cooking tests. And we also did a number of surveys in these rural homes to find out what it is that users were looking for in terms of their cookstove needs. So that was really an eye-opening and exciting experience for the students.

HAUTALA: Looking at the even bigger picture, there’s still more potential for this improved cookstove technology beyond the household kitchen. Like sterilizing medical equipment in rural areas, or providing safe drinking water.

MACCARTY: One of the most exciting things that's happened recently is that we're partnering with InStove, which is another nonprofit based here in Oregon, and they design institutional cookstoves, for places like orphanages and schools and feeding centers in rural communities. And so these are large cookstoves that have 60- to 100-liter pots. And they also have the ability to be equipped with other devices, like medical tool sterilization autoclaves. So you can put this autoclave, which is essentially like a big pressure cooker, into the cookstove and it can sterilize medical equipment, which is a huge need in rural developing communities to have that clean medical equipment. And then they've also come up with a high-efficiency, rapid throughput rapid water pasteurization system. And so you can really quickly and efficiently bring water up to pasteurization temperature, which is only 70 deg. C. Compared to when people try to purify their water, they boil it — because when you can see those bubbles, you know that water has been purified. But that's 100 deg. C., so you're using a lot more energy to boil water than is actually needed to kill the bugs. So this system is set up where as soon as the water reaches this pasteurization temperature it flows through. And so it's able to pasteurize water at a very rapid rate

[MUSIC: Firefly, Poddington Bear, used with permission of a Creative Commons Attribution-Noncommercial License]

that's essentially like turning on your kitchen faucet. And it can provide enough water for up to 1,000 people every day doing this. And it takes only about a pencil's weight of wood per liter of water. So about eight liters of water per minute with a very a tiny amount of fuel.

HAUTALA: For their work with institutional cookstoves and water pasteurization, Nordica’s team won the Impact Invention Award at the Elevating Impact Summit, organized by Portland State University earlier this year. The team hopes to perform field trials with this technology this coming summer, hopefully in Haiti.

We want to thank Nordica MacCarty for taking time out to talk to us about her work around the world. I’m going to pass the mic now to Steve Frandzel, with a different kind of story about how engineering and food are connecting the university with small-town Oregon. 

STEVE FRANDZEL: Umm, that’s  really good.

[Sound of a person eating]

Oh, hi, sorry, I’ve been waiting for you, but I just got so hungry. What I’ve got here – or what I had here – is a sope, a traditional Mexican dish. No, we haven’t changed into a food podcast, but in this segment, as you’ll see, there’s no way to separate engineering ingenuity from this delicious food, which brought together an engineering professor from Nigeria who had never heard of a sope, three women from Mexico who live in the tiny town of Monroe, Oregon and who had limited educations, a university Spanish instructor, and a determined group of engineering students on the verge of graduation. Together, they set out on a very unlikely journey. 

[MUSIC: Morenita, Texas Music Forge, used with permission of a Creative Commons Attribution-Noncommercial License]

This story begins in 2012, when Chinweike Eseonu arrived at Oregon State as a new assistant professor of industrial and mechanical engineering. He already knew about the economic decline in rural Oregon in the wake of a faltering timber industry, and one of his goals was to use technology developed at the university to drive development and investment in rural communities.

CHINWEIKE ESEONU: You had a lot of kids moving to Portland, or elsewhere, and you had just towns that were slowly dying. A number of folks had talked about options for revitalizing towns.

FRANDZEL: He drew from one of the core missions of the university.

ESEONU: We are at the land grant university in Oregon, and as the land grant, my understanding of our role is to translate benefits from knowledge or skills developed on campus to our host communities in Oregon. So we started thinking about how we could bring technological innovation from OSU to these communities. The idea of partnering with communities and having these communities actually drive the technology innovation process and have a stake in a company that comes out of that process was really intriguing.

FRANDZEL: Eseonu wanted to tap into the pipeline of ideas that already flows from the university’s research labs to established businesses and extend it to entrepreneurs in rural Oregon. About a year after arriving on campus, one thing led to another and he met Loren Chavarria, a language instructor at Oregon State, director of the Spanish for Heritage/Native Language Learners Program and a Spanish senior instructor at Oregon State. And that led to:

LOREN CHAVARRIA: Monica, Patricia and Mercedes, formerly three women from the little town of Monroe.

FRANDZEL: That’s Loren Chavarria.

CHAVARRIA: And all three of them are mostly mothers, that is their central activity at this moment, and all three of them were looking for ways to complement their family income while they could still provide plenty of time and attention to their children. So they decided to go into the food route, creating a product that was culturally relevant to the community. So the women were trying to create these sopes.

FRANDZEL: Finally, we get to the heart of the matter – in more ways than one. A sope, as I mentioned, is a traditional Mexican dish. It’s kind of like a thick corn tortilla with raised edges, like a shallow bowl, and topped with beans, salsa, sour cream, cheese, whatever you like.

CHAVARRIA: And their idea was to sell them in containers, premade sopes, sold by the dozen, in a cold case, and they came up with the idea of joining the First Alternative Co-op here in Corvallis and using them as the intermediary to sell their product.

FRANDZEL: The women named their little start up Corazon Jalisciense. Corazon, which means “heart,” because their sopes are heart-shaped, not the traditional round, and Jalisciense refers to the area of Mexico that the women came from.

CHAVARRIA: The town of Monroe has a high percentage of people from Mexico. In fact, most of them come from the same area in the state of Jalisco and they are in one way or another related to each other.

FRANDZEL: But there was a problem. Sopes are pretty simple to make, but turning them out one at a time, especially in heart shapes, is not efficient, nor does it allow for a standardized product. That’s a big drag when your goal is to sell them by the dozen. The project caught the eye of three engineering students, Jacob, Jordan and Nicholas, who took it on for their senior capstone) project under Eseonu’s supervision.

ESEONU: The goal in the capstone program is to have students engage with the client and figure out what the client wants, and then build something in response to that request. So Loren worked with us to go to Monroe to meet with the ladies, get their ideas for what they wanted out of the device. For example, we’d initially thought we were going to make a fairly large device that will be carried by two people and put onto the back of a truck and really what they wanted was something a lot smaller, a lot more portable.

FRANDZEL: Chavarria acted as both a sort of cultural liaison and translator, since neither Eseonu nor the students spoke Spanish, though one of them, Jacob, who spoke some Italian, gave it his best shot.

ESEONU: And that was wonderful because as we understood from Loren, it was really really beneficial and really helpful in building trust to have somebody try to speak Ital-Spanish. He kept going back and forth, and you could just the see that there was just this very genuine connection that developed.

CHAVARRIAH: But both groups were so open and so eager to get to know each other and to help each other and to learn from each other, that was so valuable and so important as well, that connection.

[MUSIC: Morenita, Texas Music Forge, used with permission of a Creative Commons Attribution-Noncommercial License]

FRANDZEL: Each week, the students and the women met either in Monroe or Corvallis, but only on Friday evenings, because that was the only time the women were free to get together. Think about that: Three seniors spending their Friday nights for two academic quarters to figure out a better way to make sopes.

ESEONU: The students did some work on campus, some footwork to figure out what materials they would need and how to form the materials and so on, it was really intriguing to watch them come into the meetings with the ladies on Friday nights and stay way past seven and I never once had to buy pizza, which is shocking for engineering students. So the students really drove a lot of this.

FRANDZEL: The absence of pizza was not the only thing different about this senior project.

ESEONU: In most capstone projects, the students are building something for a company, and so they can build something, it may work or may not work, the company has engineers to fix it. But in this case, they were it, so they felt a sense of responsibility for what they handed over, which just made them work extra hard.

CHAVARRIA: We had sopes like every other week throughout this process, and more or less like three fourths of the way there, the women from Monroe were not making the sopes, the students were making the sopes. They knew how to make the masa, they knew how to make the toppings, they completely embraced that food staple and they enjoyed it. It was fantastic. They got to know the siblings from the different families.

FRANDZEL: After 20 weeks, the group had a working prototype that resembled a commercial sandwich press. Think of a bulked up, no-nonsense George Forman Grill able to punch out 5 identical sope shells at a time.

ESEONU: We had this sope making device that could make 4 or 5 sopes at a time, and they could all be uniform, just an excellent excellent ready-to-eat product.

FRANDZEL: In a way, this was really just the beginning. In February of 2016, Monica and Patricia attended a conference on the OSU campus. They didn’t forget to bring the sopes. The third woman, Mercedes, had left the project because of family commitments.

CHAVARRIA: Monica spoke at the conference and then presented the audience with a samples of the sopes. And they were so delicious and so successful, that from that moment on, several people have requested them to bring sopes either here or to the city of Monroe, or to different events. So what started as the idea of creating a dozen sopes for individual households is now appearing to be that it’s going to be a catering business.

FRANDZEL: Chavarria arranged business training for the women, and a new group of students took over to refine the machine and iron out  some kinks. Eseonu is confident that Corazon Jalisciense will succeed. But this undertaking merits an entirely different measure of success – something that just can’t be quantified like sales and profits .

CHAVARRIA: This project was able to embrace so much more. If you look at the diversity goals for the university as a whole, this project was a collaboration of so many units on campus, and the benefits were not only for the students and their ability to really have a project that was practical and creative and engineer a product that was successful. But in terms of their experience getting to meet the “other,” learning about a group of people they have not had many contacts with, and I’m talking about both the women in Monroe as well as the students. In the United States, we live parallel lives between several groups, and this project created an opportunity and it was a bridge to bring different communities together.

ESEONU: Kids, especially kids from underrepresented minority families, are more likely to go into science and engineering if they understand how our work affects their lives socially. And so the children in this family have got to see their mothers’ lives enriched in partnership with engineers from OSU, and at the event that was held in February on campus, I think it was Monica who said that her son is going to become an engineer at OSU, and I tell people that if she’s anything like my mother, that’s not an idle promise.

[MUSIC: South of the Border, Audionatrix, used with permission of a Creative Commons Attribution License]

[MUSIC: The Ether Bunny, Eyes Closed Audio, used with permissions of a Creative Commons Attribution License]

FRANDZEL: This episode was produced by Keith Hautala and Steve Frandzel, with additional editing by Miriah Reddington. Our intro music is The Ether Bunny by Eyes Closed Audio on SoundCloud and used with permission of a Creative Commons attribution license. Other music in this episode includes Firefly by Poddington Bear, used with permission of a Creative Commons attribution noncommercial license, Morenita by Texas Music Forge, used with permission of a Creative Commons attribution noncommercial license, and South of the Border by Audionatix, used with permission of a Creative Commons attribution license. All sound effects in this episode were used with appropriate licenses. Links to music and sound effects can be found on our website.

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