MEXICO CITY, April 24 (Xinhua) -- In the narrow streets of Zitacuaro city in west-central Mexico, Rogelio Sosa drives his Chevy powered by non-polluting biogas produced from the prickly nopal cactus, which grows extensively in Mexico.
"A tank of 15 liters lasts me 10 days," the 66-year-old owner of a tortilla bakery said.
Since 2016, Sosa has been getting the biofuel from a small filling station run by Nopalimex, his own company that produces emission-free biogas from the cactus.
Sosa is a co-founder. His partner is Miguel Ake, an engineer who is director of the Institute of Technology of Iztapalapa in Mexico City.
The venture materialized when Sosa was looking for ways to reduce costs for his corn and cactus chip company. Now the electricity cost at his tortilla mill has been halved.
"Nobody believed in this. They told us we were crazy," said Ake, who has been studying alternative energies since 1982. He had tried to produce fuel from jatropha, yucca, maize and sugarcane but was not satisfied with the results until he tried nopal.
Nopal is so well entrenched in Mexican culture that it appears on the national flag. Ake was thinking of making biogas from the desert plant when he met Sosa.
Scientists from the United Nations Industrial Development Organization and Mexico's National Electric and Clean Energies Institute also participated in the biogas generation.
In the process, nopal leaves are first mashed in a pit and converted into biomass. This aromatic blend is then mixed with water in huge biodigestors at a certain temperature and hermetically sealed so that no oxygen can enter. The heat produces bacteria that work on the biomass and generate methane gas, which is then purified. The entire process is emission-free.
"From the moment the nopal is sowed (to) the moment it exits the vehicle's exhaust, we can say, with full confidence, that it is absolutely neutral. Zero emissions of greenhouse gases," Ake said.
Each ton of nopal produces about 100 cubic meters of biogas, which is equivalent to 100,000 liters of gasoline. It is also cheaper since each liter of nopal biogas sells for 12 pesos (64 U.S. cents) compared to the current gasoline price of 18 pesos (95 cents) in Mexico City.
Sosa said research has proven that 100 hectares of nopal would be able to generate one megawatt of energy, capable of powering 5,000 cars or 12,000 houses.
Biogas currently contributes a very small percentage of Mexico's total energy output, but the country is seeking to increase the use of clean energy and move away from fossil fuels.
Ake and Sosa want to extend their biogas project to public transport and cargo vehicles in Zitacuaro, which sees about 100,000 vehicles on road each day.
"We don't need anything more than political will to make this happen," Sosa said.
Mexico has set a target of obtaining 35 percent of its electricity from clean sources by 2024, and increasing that goal to at least 50 percent by 2050. It looks like the cactus can help Mexico reach that ambitious goal.
