No Smoking

The Search for a Stove to Save the World

For tens of millions of families in India, daily life would be unimaginable without the chulha, a brick or clay oven that’s used to cook everything from dal and curries to flat breads like roti and naan. The stoves typically burn wood, hay, cow dung, or a combination of all three. The old-fashioned chulhas burn slowly, and it’s this slow-burn that helps give traditional Indian cuisine its signature smoky flavor.

But the chulha is deadly. Like many other open-fire methods of cooking used worldwide, the chulha poses a serious health risk to its users. While citizens in wealthy nations have become accustomed to gas or electric stoves, much of the world – some 3 billion people – still rely on the ancient method of burning biomass to cook their food. The smoke from wood and dung fires includes carbon monoxide, carcinogenic polyaromatic hydrocarbons, and tiny particulate matter that can penetrate deep into human lungs. Daily smoke exposure contributes to pneumonia, low birth weight, chronic respiratory disease, and heart disease. According to the World Health Organization, breathing the smoke from traditional cookstoves and open fires causes nearly 2 million premature deaths a year. Half of those deaths are children younger than five.

Old-fashioned cooking methods also contribute to global climate change. The black soot from fires darkens snow-covered peaks and glaciers, intensifying heat absorption and accelerating ice melt.

So a global race is on to develop efficient cookstoves that can address the twin threats of household air pollution and global warming. In 2010, US Secretary of State Hillary Clinton launched the Global Alliance for Clean Cookstoves, a public-private partnership that includes 35 countries and more than 300 universities, nonprofits organizations, and companies focused on developing and deploying better cooking technology. The alliance has set a goal for itself of distributing clean cookstoves to 100 million households worldwide by 2020.

The specifications for a clean burning stove are clear enough: A modern, efficient stove needs to reduce fuel use by at least 50 percent and cut black soot by more than 60 percent. It also needs to be durable, able to last more than 5 years with daily use. And, crucial for a product geared toward the poorest of the world’s poor, it needs to be cheap, retailing for less than US$10.

This isn’t as easy as it may sound. Catering to the specific needs of local traditions is a central hurdle. The requirements for cooking tortillas in Mexico are different than what’s needed to make injera in Ethiopia or rice porridge in China. Fuel source is another complication – wood burns differently than dung, and stoves need to be designed accordingly. The details are so daunting that an appropriate technology research center called Aprovecho hosts a yearly “Stove Camp” in Oregon that brings together industrial designers, tinkerers, and tech do-gooders to perfect stove designs.

At the same time, the ideal stove has to have enough universal appeal to be mass-produced. Otherwise, there’s no way to keep the price low enough to be attractive to buyers – and to have a sizeable global impact. Spending $8 for a stove might not seem like a lot, but for a family that lives on less than $2 a day and is accustomed to cooking for free over an open hearth, it’s a luxury. Such a low price point, however, has dissuaded some major manufacturers from going into the business. The market might be huge – experts estimate that as many as 800 million homes worldwide need improved cookstoves – but the profit margins are slim.

A nonprofit enterprise based in Colorado, Envirofit, is one organization that has found a way to balance all of the competing factors. Since 2003 it has sold more than 350,000 stoves (a variety of models that burn wood or charcoal) to families in South America, Africa, and Asia. As it markets its products, Envirofit has found that the best selling point isn’t the health benefits of clean stoves, but rather a basic quality of life improvement: Because they burn more efficiently, Envirofit stoves decrease the amount of time women and children have to spend gathering fuel. A testimonial on the Envirofit website by a Kenyan woman named Chukulisa Karani is typical: “It saves wood and saves my money because I don’t have to walk 14 kilometers every two days for more wood. It gives me more time with my boys, and for me that’s the most important benefit of all.”

Building a stove to save the world, it turns out, will rely on saving that one thing we are all short of on a warming planet: time.

—Jason Mark