In Mozambique, as in much of the world, people cook with charcoal. The dirty fuel causes smoke and soot to billow into their homes. As a result, cardiovascular and lung diseases are rampant from breathing such smoky indoor air—a problem that kills at least two million people worldwide prematurely every year, primarily women and children. Burning charcoal to cook exacerbates pneumonia, emphysema, tuberculosis and even low intelligence, among other human health issues. To solve the problem in the capital city of Maputo, Danish enzyme-maker Novozymes and its partners, like many before them, wanted to introduce a cleaner cookstove.
 
The ambition did not stop there. Novozymes hoped to bring an entire bio-based economy to the southeast African nation, starting with improved crop rotations that would allow farmers to grow excess cassava. The cassava in turn would be fed to a donated ethanol-brewing facility, built in the town of Dondo. The ethanol would be the fuel in cookstoves, burning more cleanly and emitting far less harmful soot and gases.
 
The effort, known first as CleanStar and then NewFire, tried several ways to make its business a success, including redesigning the stove itself to include two burners, which enabled people to cook traditionally with a pot of beans bubbling next to a meat or other dish. And ethanol offered other advantages over charcoal including being able to turn it on or off and get heat immediately rather than waiting for a charcoal fire to get hot. "The convenience and speed and time saved is actually important," Anders Lau Tuxen, a Novozymes senior project manager who also served as chairman of the board of CleanStar Mozambique, told Scientific American in 2013 before he left both companies. "Also, cleanliness and safety have value."
 
Problems, however, were legion. First, not enough farmers could be convinced to adopt the new rotation system involving nitrogen-fixing beans and peas along with staple crops. As a result, not enough surplus cassava could be grown to feed the new ethanol fermentation plant. Nor could Mozambique's bad roads and old trucks transport any existing excess cassava to Dondo, causing the plant to shut down in November 2013. Fighting among government and rebel forces in 2013 did not help nor did the slow process of securing additional money from carbon credits sold on the international market as a result of all that displaced charcoal.
 
The company had to sell the stove at a loss and the effort never reached more than 5 percent of the population of Maputo, thanks to the expense of ethanol compared with charcoal. "We simply haven't even made a dent in the charcoal market," Tuxen said, even where the effort was succeeding.
 
Sales of the ethanol stoves themselves kept growing in Maputo, reaching more than 3,000 per month and still growing. More than a million liters of ethanol brewed from molasses had to be imported from South Africa to fuel those 33,000 stoves. "The demand for ethanol was actually there," says Johan Melchior, a Novozymes spokesman. "For consumers it was an attractive source of cooking fuel." Even so, sales of the more expensive ethanol could not cover the cost of importing the fuel. "If we had been able to successfully produce it at our own facilities at a low production cost, then we might have been successful," Melchior says. "We still believe it can be done and should be done and we hope that others will learn from our mistakes and achieve success at a larger scale."
 
Novozymes and its partners decided to file for bankruptcy this year and seek local buyers for the various parts of the project. "They're still selling ethanol from the stock down there," Melchior says. "It was just a realization that we were not the right ones to run retail in Maputo."
 
So CleanStar/NewFire joins a litany of clean cookstove efforts on the scrap heap, undone by the complexity of the project as well as the fact that charcoal is cheap and cleaner cookstoves are much more expensive than dirtier alternatives despite the cost in human health and the deforestation that results from harvesting charcoal. As it stands, roughly 40,000 square kilometers of forest are cut and burned annually to make charcoal and the World Health Organization notes that indoor air pollution from wood and coal stoves is a leading global killer. The U.S. State Department is still making and distributing cleaner cookstoves as part of its Global Alliance for Clean Cookstoves and aims to get them into 100 million households by 2020, an effort that could well be the cheapest way to stave off global warming by reducing soot in the atmosphere along with deforestation. The list of needs for these stoves is long: cheap, durable, easy to use and clean—and a solution that fulfills all these criteria has eluded the best efforts of engineers for decades at this point. In fact, the Global Alliance is the successor to a 10-year effort by the U.S. Environmental Protection Agency to find a better stove as part of its Partnership for Clean Indoor Air. From rocket stoves that burn wood at high temperatures to ensure complete combustion and therefore less soot to even more complicated stoves that rely on a battery-powered fan to reduce pollution, no single stove has been able to meet all the needs of people cooking with charcoal.
 
In Maputo, local investors, led by Thelma Venichand, former sales and marketing director for CleanStar, have purchased the part of the business that covers sales of ethanol and the cooking stoves, called NDZiLO Mozambique. But the smell of smoke remains ubiquitous in Maputo and the rest of the country, where a bio-based economy remains out of reach—as it does in the rest of the world. "We still believe that bio-ethanol is a good substitute for charcoal," Melchior says.
 
Or, as Tuxen told Scientific American back in 2013 as the company struggled to survive: "It's never easy to develop a new market in a developing country."