The increasing demand for energy, growing scarcity of fossil fuel and environmental concern have stimulated the policy makers in US and Europe to search for alternative sources of energy and the agricultural sector can be a viable solution to this problem. This analysis is addressed to the study of a feasibility of the agro-industrial chain, including farms and industrial plants, to produce biofuel as though it were an "island economy", i.e., a net energy exporter only if the energy and economic values of the biofuel and its co-products exceeds that of all direct and indirect energy inputs. More specifically, the analysis is dedicated to economic, energetic and ecological aspects of the energy cogeneration approach that complete the "Island Model" and demonstrate to be more sustainable to afford competitively the economic and energetic problems. This model is based on sunflower crop used for production of biodiesel, while the co-product sunflower meal is used in the dairy production, the wastes are recycled in biogas production to generate electricity and heat, and the final residual compost is used for fertilization. This integrated farm energy cogeneration project (IFECO) requires to analyze the different steps of the agro-industrial chain and to afford investments in energy plants and operating costs; to manage the integrated agro-industrial energy chain more skilled labour is required; hence, the convenience to operate IFECO will depend on the capacity to organize and coordinate the many activities performed at different chain steps, with achievement of scale and scope economies. The macroeconomic targets as occupation, value added, import of energy products and inflation, justify the public intervention in programs directed to biodiel defiscalization and support of the energy crops such as soybean, sunflower and others. The results obtained from IFECO suggest that the total energy produced by sunflower chain is significantly superior to the energy spent, the economic gain is reflected in a considerable increase in the annual income and value of land from capitalization of permanent net farm income; finally, the life cycle GHG savings from displacing the fossil fuel (reduction in CO, VOC, PM10, SOx, Nox) are a valuable contribution that ameliorate the ecological conditions of the biosphere and must be considered as a market value if the Kyoto Protocol is to be applied.

renewable energy; biodiesel; cogeneration; sunflower