For 17 months between 2014 and 2016, Tara Ramanathan spent a lot of time looking at a dashboard on her tablet, watching for incoming data updates. She and her colleagues at Nexleaf Analytics—a non-profit technology company that develops public health and environmental data analysis tools—had been engaged as the data tracking experts on a pilot program with Project Surya to monitor household cooking habits in the Indian state of Odisha. The team had distributed 456 clean cookstoves to village families, each stove outfitted with a monitoring device that contained a temperature sensor and wireless SIM card. Every time a stove switched on, it would transmit temperature data via SIM to the cloud, where it arrived to Ramanathan’s dashboard.
At one point, the team noticed that some of the stoves’ usage dropped to zero. It turned out that they had broken. “That type of feedback was exactly what [we] wanted to happen,” Ramanathan says. “Without the wireless monitoring, we wouldn’t have known that.”
If it sounds like overkill to outfit cookstoves costing US$40 to $80 with temperature sensors and SIM cards, Nexleaf’s view is that monitoring is a vital step in the development of successful new technologies, particularly those focused on tackling global health problems. The non-profit organization, which was founded in 2009, is developing a variety of temperature sensors to use in rural field projects, where health initiatives are needed but objective data is difficult to collect. Its two key products—StoveTrace and ColdTrace—are used for tracking clean cookstove usage and vaccine storage temperatures respectively.
Nexleaf and its StoveTrace sensors have been working with Project Surya and its partners, the University of California San Diego and The Energy and Resources Institute (TERI), since the project was founded in 2009. The initiative was started with support from the National Science Foundation and Qualcomm Wireless Reach with the aim of encouraging usage of cleaner, healthier and more sustainable cooking technologies.
Nearly three billion people in the world still cook their meals over open fires or traditional stoves, which are fueled by wood, twigs, dung and other biomass, or charcoal made from cut down trees. This may be how humankind cooked for thousands of years, but with climate change concerns and a rapidly growing global population, it is no longer sustainable. Neither open fires nor most traditional cookstoves burn fuel efficiently or cleanly. In turn, they produce plumes of smoke and soot—also called black carbon—which is destructive to both human and environmental health.
Environmentally, black carbon is the second largest contributor to global warming after carbon dioxide. In India—where two-thirds of its 1.2 billion-strong population still cook with biomass fuels—nearly half of its annual black carbon emissions come from burned biomass, according a study published in Nature Geoscience. The impact of these emissions is visible in the Himalayan Mountains, where particles form black residue on the snow, absorbing heat from the sun and accelerating snow and glacier melts.
More immediately, black carbon takes a significant toll on human health. “It is estimated that 4.3 million people die each year from exposure to these particulates,” says Martin Lucak, Nexleaf’s founder and CTO. “That’s more than malaria, HIV and tuberculosis combined.” Women and girls, who are most exposed to cookfires, are disproportionately affected, along with the children and babies in their care.
Chemistry of cooking
The harmful particulates that waft off of burning wood or other biomass are a product of incomplete fuel combustion. When these products are set on fire, water trapped within begins to evaporate, and once the water evaporates completely, biomass can heat to hundreds of degrees Celsius. Wood, for example, can reach up to 300 degrees, at which point it begins to pyrolyse, or break apart from the fire. This process releases vapors containing various carbon compounds, often referred to as wood gas, and the wood devolves into char. Incidentally, anyone who has burned bread has witnessed these pyrolytic destruction phases.
Wood gasses make excellent clean fuel, but they need a certain amount of heat and oxygen to ignite and keep burning. “To achieve clean combustion, you need the three Ts: time, temperature and turbulence,” explains Kathleen Lask, from the University of California, Berkeley’s Gadgil Lab for Energy and Water Research. But there is not enough heat or oxygen in open fires and most traditional cooking devices for the wood gasses to burn fully, which results in incomplete combustion. The gasses are instead released into the atmosphere in the form of black smoke.
Black carbon is the second largest contributor to global warming after carbon dioxide. It also takes a significant toll on human health.
By contrast, clean cookstoves, like the ones distributed in the Project Surya pilot in Odisha, are designed to funnel more oxygen into the fuel chamber to enable more complete combustion. “The idea is to add turbulence to try to break out the heavy fuel zone so air can get in and react with the fuel,” Lask explains. The process, called fuel gasification, allows those gasses to be used as extra fuel. Clean cookstoves are better able to harness this process and produce longer-lasting heat from biomass than open fires and traditional cooking vessels. Efficient fuel gasification also gives clean cookstoves an economic advantage, because cooks get more out of the same amount of fuel.
Knowing the burning process, experts can easily build cookstoves that solve issues around burn efficiency and particulate emissions. Indeed, momentum in the clean cookstove technology sector has been building for nearly 30 years, when some of the earliest so-called “improved stove” designs were conceived. Getting people to use them is a different challenge entirely, however. Food preparation is a highly culturally nuanced activity; cooking tools, vessels and methods therefore vary widely form one geographic location to another. Cooking methods also depend heavily on available food and fuel types. Cookstoves therefore need to be able to accommodate the cooks’ preferred vessels, whether that is a pot or cauldron or grill-top for making flatbreads.
In Haiti, for example, where Lask studied cookstoves distributed after the 2010 earthquake, rice is a staple food, and to cook it, traditional, charcoal-fueled stoves are built with a large surface area for maintaining a large fire for boiling and a small fire for simmering. But often improved cookstove designs include only one burner. “Haitian cooks reported sometimes significant difficulties with the improved stoves [that were distributed], including an inability to manipulate the charcoal to adjust the heat,” Lask wrote in her study. “One stove, for example, required users to remove the pot and turn the stove upside-down to shake out burning charcoal in order to lower the heat enough to simmer the rice, a major inconvenience and potential danger.”
Meanwhile, in Nigeria, regular family meals often include as many as 40 people, which means that cooking surfaces have to accommodate very large pots, and in Ethiopia, women typically cook inside the home and are less inclined to use stove types that spew ash onto the floor.
Lack of understanding about regional and cultural cooking requirements is one of the key reasons cookstove designs and cookstove adoption projects fail. “It is unrealistic to expect people to change their behavior—they will just keep cooking the old way,” Ramanathan explains. “To be used, stoves need to be user friendly. They need to fit the needs and lifestyles of the women.”
Patricia Chin-Sweeny, co-founder of the business strategy and investment advisory firm I-DEV, says her team has witnessed many failures through their work on behalf of clean cookstove ventures and organizations like the World Bank and Global Alliance for Clean Cookstoves (GACC). “We [have seen cases where] people don't use the stoves, because they can’t cook the food they need,” she says. “They stack them in the corner, or take a $50 cookstove and sell it for $2 at the local market.”
Ironically, the regionally and culturally-nuanced nature of cookstove initiatives means that a lot of work in the field—including the success stories—is disconnected and fragmented. “Because cooking is an issue so central to everyone’s lives and what happens in their homes, it really needs a comprehensive approach,” explains says Raynee Chiang, director of standards, technology and fuels at GACC. Her organization was launched in 2010 to support the evolution of a global market for new cooking technologies, and key to the market’s success, she says, is understanding people’s cooking habits and preferences around the world.
This is what organizations like Nexleaf are trying to support through remote monitoring devices. Until recently, monitoring for cookstove projects was primarily done via user surveys, which asked people to report how much they used the stoves they were given. Stove makers and distributors found that the information reported was not always reliable, however, and sometimes outright false. Daniel Wilson, postdoctoral fellow at Gadgil Lab, recalls collecting data from users on a stove the lab designed for Darfuri refugees in Sudan in the early 2000s. “People said they used [the stove] three times a day, five hours a day, when it was really zero hours,” Wilson says. This was because people did not want to refuse the product they were given; rather, they accepted it and then opted not to use it. The feedback highlights why organizations that donate and distribute technologies that are unfamiliar to their target users with little teaching and follow up are unlikely to see successful adoption.
Project tracking is logistically difficult and costly in remote areas or among transient populations, however. This is why Wilson’s team partnered on the Darfur Stove project with Berkley Air Monitoring Group, which had developed temperature sensors called iButtons that could be affixed to the Lab’s distributed stoves. The sensors would wake up every five minutes, measure the stove’s temperature, and store the data on an internal chip. They could capture up to a year’s worth of temperature readings for retrieval.
The Gadgil Lab team wanted to know more than just how much their own stove was put to use, however; they wanted to understand the extent to which people switched to clean technology. So to conduct a more accurate assessment, they also outfitted users’ traditional stoves with sensors. “To get the health benefits, you need to minimize the traditional stove usage [to] no more than once a week,” says Michael Johnson, senior scientist at Berkley Air Monitoring Group. Specifically, traditional stoves should be used no more than one to three hours per week to meet World Health Organization particulate matter targets, he adds.
Outfitting the traditional stoves with sensors was not as simple as it sounds, however. For one, gauging where to position the sensors was tricky, because the stoves were irregularly shaped. The positioning was nevertheless important to collect accurate temperature readings. The sensors also raised the cost of the project: individual iButtons could cost as much as $80—more than the cost of the Darfur Stove itself—and adding them to both the improved stoves and the traditional stoves added up quickly, especially because many homes used multiple stoves, Johnson says. “If you have 100 homes and you need three [sensors] for each home it can be quite expensive.” Nevertheless, the sensors allowed the team to get realistic data on whether the project’s overall environmental goal was being achieved or not.
The one significant obstacle that the iButtons presented to remote monitoring was that they could not produce real time data. Rather, to collect the sensors’ data, the project team had to visit each iButton with a device reader in the camps and remote villages where they were deployed. For this reason, the iButtons also could not inform the team of immediate problems. If a stove broke or a family stopped using it shortly after they got it, the team might not find out for months.
These are issues that today’s remote sensors can better contend with, thanks to maturing technology and wider internet and cellular network access. With Nexleaf’s StoveTrace, for instance, the team solved the problem of obtaining real-time data with wireless SIM cards and cloud data storage. An earlier iteration of the device ran off of actual cell phones connected to a temperature probe on the stove. “It was an easy off the shelf solution. We didn't have to manufacture it, and we could get a lot of data with it,” says Lucak. But using a cellphone even for a few dozen stoves, let alone a few hundred, was expensive, which is why the team ultimately developed the SIM card design.
One other major development in today’s sensing technology is the ability to track air quality along with stove usage. Using a device called PATS+, which stands for Particle and Temperature Sensors, Berkley Air Monitoring Group can measure the improvement of the house air quality and reduction of particulate matter. Nexleaf has also adopted the PATS+ devices, however, they are expensive, costing $500 to $600 each, and cannot yet prove data in real time.
Understanding and developing cookstove models that global users will readily embrace and purchase may be wrought with obstacles, but with a three billion-strong base of potential customers, the market is certainly ripe for savvy manufacturers and distributors. This is ultimately what monitoring technologies endeavor to support.
One key part of cracking that market is understanding the stove features different users around the world need and expect, like the model Gadgil Lab built specifically for Darfuri refugees. But it is also a matter of figuring out how to design stove products that are accessible to low-income customers. This means both pricing the products appropriately and unlocking financial options and incentives that will encourage people to buy them.
Chin-Sweeny recalls helping cookstove manufacturer BURN discover a new market in its own backyard in Kenya. The I-DEV team had been hired by the World Bank to assess the market viability of refugee camps and other settlements across Africa. One particularly promising market it discovered was in the Kakuma refugee camp in northwest Kenya, which is home to 200,000 people from 20 countries. A 25-year-old camp, Kakuma operates more like an independent town with its own markets, shops and internet cafes. Residents still rely on humanitarian aid, but also work and pay for goods, including as much as $20 per month on energy costs. After observing daily life in Kakuma, Chin-Sweeny’s team concluded that residents would be interested in purchasing improved cookstoves, especially if an installment-based payment option was available. Her team introduced the idea to BURN.
“BURN wasn’t interested in going to refugee camps before we talked to them,” Chin-Sweeny says. “Now they know they can sell there. It can be a lucrative and concentrated market.”
With Project Surya, Nexleaf hopes StoveTrace will help prove that women in particular are an under-tapped but powerful change agent in the push for clean cookstove adoption. “Involving more women in stove production and distribution is central to our [collective] work [in the sector],” says Chiang of GACC. This is because women and girls are responsible for household cooking, including collecting or purchasing fuel, and because they are most vulnerable to the health and socio-economic costs of traditional cooking practices. “Involving women results in more sales and better technology adoption,” she adds.
Nexleaf hopes sensors will help prove that women in particular are an under-tapped but powerful change agent in the push for clean cookstove adoption.
To this end, Project Surya is testing a new financial incentive for women to use clean cookstoves, by way of a carbon credit-based climate fund in India, backed by Leslie and John “Mac” McQuown. Through the pilot, women can receive a $40 to $80 loan from local banks and other partners to purchase a new cookstove. The women then receive payments from the fund for using the stove, which StoveTrace tracks. Payments are assessed at $12 per ton based on the U.S. Environmental Protection Agency’s estimated social cost of carbon and then disbursed as mobile money.
“The money is only released to women when cooking data shows usage, but it will go directly to women’s hands,” Ramanathan says. She approximates that each woman can earn up to $64 annually. The hope is that the model will be self-reinforcing. “If women see money coming to their pockets every week, that incentivizes usage,” Ramanathan adds.
The next phase of the project will be to train 1,000 women in India to teach other women about the health and financial benefits of switching to clean cookstoves. Graduating to this next phase depends, of course, on solidifying the suitability of the cookstove models being tested for these markets and ensuring that the carbon-offset repayment model is sound. The collective Project Surya team hopes the effort could be a potential game-changer in clean cookstove adoption. But the only way to know for sure is by following the data.