by Raúl Gutiérrez

SANTA BÁRBARA, El Salvador, (IPS) - He used to make land mines to stem the advance of the army during El Salvador 's 1980-1992 civil war. But today, former guerrilla fighter Félix Vásquez uses his know-how to transform cow manure into biogas.

Vásquez or "El Rocketero" (The Rocketeer), as he was called when he was active in the insurgent Farabundo Martí National Liberation Front (FMLN) because of his skill in making homemade weapons, says he is convinced that the production of biogas, even in small quantities, can contribute to curbing the growing deforestation in his country and help campesino (peasant farmer) families cut their living costs.

"The very aim we used to have, which was somehow to create a tool to kill someone, even if it was in self-defense, today is of use to us to address environmental problems and the economic difficulties faced by families," Vásques, 42, said on a tour of his backyard, where he has begun to install biogas-producing equipment, known as a biodigester, next to his pigsty and chicken coop.

Vásquez had only completed fourth grade of primary school before the armed conflict broke out. He admits that at first he "knew nothing" about things like biogas production, and that only after the peace agreement was signed in 1992 did he make it to secondary school, which is where his interest in chemistry was reawakened. He is now an enthusiastic promoter of biodigesters, which produce the green-friendly biogas through the fermentation of organic matter including manure, sewage sludge, municipal solid waste, biodegradable waste or any other biodegradable feedstock, under anaerobic conditions. Biogas is comprised primarily of methane and carbon dioxide.

A small bio digester built in the Philippines

According to Vásquez, installing a biodigester does not require in-depth technical knowledge or a major investment, as the cost runs to no more than 300 dollars. The equipment can be homemade, apparently poses no health risks, and does not produce offensive odors. Because Biogas can be used as a fuel for vehicles or to generate electric power, and can also be burned directly for cooking, heating and lighting it helps cut family fuel expenses. The airtight biodigesters

often consist of a cement tank covered with dark plastic sheeting, or several barrels soldered together. The biogas plant is fed with diluted manure through a tube or hose, and has an outgoing biogas valve made of PVC.

The Chilean Evangelical Service for Development (SEPADE) notes that contrary to what most people think, agriculture accounts for 30 percent of all emissions of methane, which is the second most important greenhouse gas, after carbon dioxide. SEPADE points to the environmental benefits of installing biodigesters on farms to make use of manure, in order to cut air pollution and produce renewable energy, and says such equipment will be "indispensable" in the future.

Biodigester technology has grown in popularity in Latin America over the past few decades, and is currently used to produce electricity and for heating purposes in large plants in countries like Chile and Costa Rica . The technique is also increasingly widely used in projects in Central America . In El Salvador, several families in Santa Bárbara, a town of around 2,000 people in the northern province of Chalatenango, are producing biogas, and have thus cut their use of firewood for cooking by 50 percent.

José Luis Guerra is one of the local residents who has built his own biodigester in his backyard, using barrels soldered together. Starting out, he used 24 buckets containing 28 litres of manure diluted with water. Eight days later, his wife was able to use their new three-burner biogas stove for cooking. "This has benefited us quite a lot. We want to keep working on this, to see if we can produce half of the fuel that we need," says Guerra. So far, the Guerras have reduced their consumption of propane cooking gas by one-third.

Juan René Guzmán, an official with the United Nations Development Programme (UNDP), explains that the initiative, which got underway a year ago, is aimed at raising awareness among people in the area on the advantages of producing renewable energy using biodigesters, and of the use of "improved stoves", which reduce firewood consumption by up to 90 percent. "We have obtained very good results, and additional benefits in terms of health," says Guzmán, national coordinator for the Small Donations Programme, which provides up to 25,000 dollars a year to help implement the project.” These are not United Nations projects; they are run by the communities themselves."

The Small Donations Programme supports initiatives organized by other entities or local residents, facilitating the participation of local people in the promotion of biodigesters and improved stoves, with an "integral vision" that takes into account the strengthening of skills, democratic development, environmental education, and promotion of health. The project, which has the support of the Salvadoran government, has approved the installation of six biodigesters and 40 stoves which, if they are used adequately and have the hoped-for multiplier effect in Santa Bárbara, should contribute to sustainable development, since farmers already have the raw material for producing biogas.

The U.N. Food and Agriculture Organization (FAO) reports that El Salvador is the Central American country that has suffered the worst environmental degradation, with over 75 percent of the soil suffering erosion to some degree, as a result of deforestation, urbanization and the heavy concentration of the population. El Salvador is the second most deforested country in Latin America after Haiti, with less than five percent of the land area forested, and hardly any primary forest left.

A FAO report on non-timber forest products in Central America says firewood represents 92 percent of energy consumption in the Salvadoran countryside, and between 51 and 69 percent nationwide. This, along with the expansion of the agricultural frontier, has driven up deforestation to an average of 4,500 hectares a year.

Vásquez, meanwhile, complains that despite the proven benefits of biogas, "there is no state support for experiments in alternative energy sources. That is why we have not produced biogas on a large scale," he says, adding that if urgent, responsible action is not taken, El Salvador will win the dubious honor of being the "leader in deforestation."