Evaluación exergética de la producción de etanol en base a grano de maíz: un estudio de caso en la Región Pampeana (Argentina)

Autores/as

  • Diego O. Ferraro IFEVA, Cátedra de Cerealicultura, Fac. de Agronomía, Univ. de Buenos Aires - CONICET, Bs. As., Argentina.

Palabras clave:

sustentabilidad, agricultura, deterioro, exergía

Resumen

La transformación de los sistemas naturales en sistemas productivos altera no sólo su estructura sino también su funcionalidad. La necesidad de evaluar y monitorear esos cambios funcionales ha llevado al desarrollo y la aplicación de un gran número de indicadores del impacto de las actividades humanas sobre los ecosistemas. En este trabajo se presenta un marco teórico para el estudio del deterioro de los ecosistemas agrícolas a través del análisis de los flujos de energía. Se presentan los fundamentos de la evaluación del funcionamiento de los agroecosistemas a través del uso de la energía útil o exergía, y se ilustra la metodología de cálculo en un sistema agrícola de la Región Pampeana destinado a la producción de etanol sobre la base de grano de maíz. Los resultados indican que si bien el impacto potencial en términos de extracción de recursos (bajo la forma de exergía consumida) es mayor en la fase industrial, las ineficiencias en la fase agrícola son mucho más marcadas. En cuanto al ciclado interno de exergía, los resultados de este trabajo indican que 41% de la exergía utilizada para obtener 1 MJ de exergía proviene de fuentes no renovables, y se eleva a 71% si se toma en cuenta el aporte neto de exergía del combustible, después de descontarle los costos exergéticos acumulados durante los procesos de elaboración. Estos resultados indican que el sistema analizado de producción de etanol sobre la base de maíz cumple de manera parcial las condiciones deseables de baja extracción de recursos del ambiente y alta renovabilidad de la producción.

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Publicado

2008-12-01

Cómo citar

Ferraro, D. O. (2008). Evaluación exergética de la producción de etanol en base a grano de maíz: un estudio de caso en la Región Pampeana (Argentina). Ecología Austral, 18(3), 323–336. Recuperado a partir de https://ojs.ecologiaaustral.com.ar/index.php/Ecologia_Austral/article/view/1379

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Sección Especial