Source: David Biello, Scientific American, May 31, 2012
Ethanol Scheme Bids to Clean Up Cooking
A new effort aims to build a for-profit, bio-based economy in Mozambique involving rotation farming, ethanol and clean cookstoves
A farmer in Mozambique grows peas, beans and cassava in rotation—enough to feed the family with a little to spare. The farmer then sells that excess to CleanStar Mozambique, which dries and packages the produce for sale in the capital, Maputo. But the company also takes the surplus cassava, a starch-filled root and local food staple, and sends it to an ethanol fermentation plant built by ICM, a U.S. ethanol company, that employs enzymes produced by Denmark-based Novozymes. The ethanol produced is then sold in reusable plastic bottles to people in Maputo who own one of the 3,000 or so ethanol-burning clean cookstoves sold by CleanStar. When the fuel runs out, more can be purchased at an incipient network of CleanStar shops.
“We want to show that there is this idea of a bio-based society,” says chemical engineer Thomas Nagy, executive vice president for stakeholder relations at Novozymes, which helped start and fund the scheme. “This is not a philanthropic project.”
Novozymes and its corporate partners hope to create a bio-based, sustainable economy in Mozambique. Such an economy could point the way to reducing the two million annual deaths worldwide that result from breathing in smoky indoor air caused by burning charcoal. Currently, charcoal is the fuel of choice in much of the world and a nearly $10-billion market across sub-Saharan Africa. That is the market this ethanol-burning cookstove—and bio-based economy—aims to disrupt.
“Ethanol burns very clean,” Nagy notes. The CleanStar venture opened its first ethanol production plant on May 17 in Dondo, capable of brewing two million liters of fuel per year. “Charcoal might be cheaper but it has less energy content per kilo[gram].”
The problem in this case is: replacing cheap charcoal, which farmers make by cutting down and burning trees, requires dependence on a much more complex, new and unproved system. “People use charcoal because it is cheap and easy,” notes a prominent development expert who declined to be identified because of relationships with various clean cookstove donors and providers. “Ethanol is neither.”
Food and fuel
The first step in this new process will be convincing farmers to halt charcoal production and slash-and-burn agriculture in favor of a new rotation system. Mozambican farmers currently grow corn and cassava, among other crops. But under the new system, they would grow nitrogen-fixing beans and peas along with staple or cash crops such as cassava, ground nuts, sorghum and soybeans in rotation in fields ringed by trees newly-planted to prevent erosion. “We have enrolled between 500 and 600 farmers today,” Nagy says, and the project aims for at least 3,000 by next year. The CleanStar venture also provides each farmer with fertilizer and pesticides as well as technical assistance.
As a result of the new rotation system and improved soil fertility, farm family nutrition improves (44 percent of Mozambican children are stunted due to malnutrition and disease) and income can more than quadruple, according to Nagy. Selling the excess to city dwellers will improve their nutrition as well—and cut down on food imports. The excess cassava, also known as tapioca when dried to a powder, will be turned into a fuel to vie with charcoal and, in a bid to ensure that the staple crop does not end up being diverted from hungry stomachs to stoves, CleanStar will pay less than the crop’s price as food.
CleanStar Mozambique, the local offshoot of New York City–based investment firm CleanStar Ventures, will also handle the ethanol distribution in Maputo as well as sales of the stove, known as the NDZiLO stove and manufactured by Sweden-based firm Dometic. The locally assembled stoves are like butane-burning camping stoves, with an adjustable flame, no moving parts, and come with a five-year warranty. “There’s a pretty good history of durability of this equipment,” Nagy says.
That warranty is there, in part, to ensure that the stoves are used, providing technical support if something goes wrong. And that’s to ensure that the carbon credits associated with the use of the stoves, purchased by Bank of America Merrill Lynch, are real. Each stove will generate roughly four carbon credits per year of use, according to Novozymes, which can be used in emissions trading markets in Europe or Australia. The additional money from the carbon credits then enables CleanStar to sell the stoves not at their cost of $70 but at a carbon credit–subsidized price of $30. That’s roughly equivalent to a high-end charcoal stove, although the cheapest versions cost closer to $4, but without the belching soot and its attendant cleaning and health problems that help limit the average Mozambican’s life span to 47 years.
Then there’s the fuel cost. Whereas ICM donated the ethanol plant, CleanStar will sell the ethanol for roughly $1.60 per liter. By comparison, a canister of charcoal costs less than 50 cents, although it results in deforestation and respiratory disease. The only other alternative at present is propane, which also requires its own expensive stove in addition to being a more expensive (and imported) fuel.
The average Mozambican’s income is $1 per day and charcoal prices have doubled in the last three years as forests recede farther from the capital. Mozambique is not unique in this regard; across Africa, 80 percent of households rely on charcoal, which results in roughly 40,000 square kilometers of forest being cut and burned annually across the continent.
CleanStar’s idea is to replace 20 percent of charcoal use in Maputo with ethanol by 2014, a bid that would require some 80,000 such stoves and eliminate 40 square kilometers of forest clearing annually, according to promoters. “CleanStar has to make a profit, because if it relies on donations or goodwill from suppliers, it will collapse,” Nagy notes. “We want to demonstrate that the bio-based economy is a sustainable business proposition for the least-developed countries,” like Mozambique.
At the same time, there is nothing to say that the trees ringing the fields employing the new methods would not be harvested for charcoal in a few years’ time. And, until the new ethanol plant in Dondo is running at capacity, the fuel for the stoves would be imported from South Africa. “Either it’s a really smart way to address several problems at once or it’s a recipe for disaster,” says international development worker and blogger Alanna Shaikh. “Programs this complex usually go the way of disaster…. It’s just so difficult to get people to change cooking methods.”
Barriers to entry
This new ethanol scheme will require all its parts—harvest collection, packaging machinery, fermentation plant, bottling, distribution and stoves—to function well in concert. Yet, in Mozambique, it is challenging to maintain municipal water supplies due to a lack of funds and technology, among other infrastructure woes. At the same time, ethanol will be competing with a fuel that, although dirty, is desirable because it is cheap and relies on only land and labor as an input. “There is no way ethanol is going to get down to charcoal prices anytime soon,” the development expert who declined to be identified notes. “We’re back to ignoring local knowledge in the name of new technologies that will fix all of the problems the local population simply cannot manage.”
In addition, a fuel switch from charcoal to ethanol would have complex social impacts, ranging from the loss of livelihood for those involved in charcoal production to the loss of other economic opportunities by those spending more money on ethanol fuel. And, whereas the ethanol stoves could certainly have significant public health impacts, they may not contribute much to solving the greenhouse gas emissions and deforestation driving global warming. “Cooking fuel use is not the biggest driver of deforestation by any stretch,” argues the development expert who declined to be identified, who notes that land clearing for agriculture has a much larger impact. “There are many efforts to design and market cleaner burning, more efficient charcoal stoves out there. Any of these would make more sense.”
In fact, building and distributing less polluting cookstoves is the focus of a $250-million effort from the U.S. State Department, known as the Global Alliance for Clean Cookstoves. The program aims to install cleaner burning cookstoves, whether solar-powered or simply more efficient at burning charcoal or wood, in 100 million households worldwide by the end of the decade. The U.S. Department of Energy, for its part in this global effort, has offered $2.5 million in funding to develop better stoves. “Many challenges remain to develop high-performing technologies that are also affordable, durable, easy to use and meet international air quality guidelines,” said Secretary of Energy Steven Chu in announcing the funding on April 13.
In the meantime CleanStar has sold out of its initial allotment of 3,000 stoves and is accepting preorders for the next batch as well as enlisting farmers. “From interest to reality, there is a mountain to climb,” Novozyme’s Nagy admits. “We’ll give ourselves a year to scale it up and see if it actually works.”