Avaliação da disponibilidade de terras e do potencial bioenergético em 2050 considerando os limites da segurança alimentar

Abstract

This study evaluates the potential of available land areas for bioenergy production in 2050 without compromising food security limits. The estimates contain the global population food demand, the agricultural production supply, the availability of surplus land that could be used for biofuels production, and the bioenergy production potential in the remaining area. The novelty of this article is the qualitative and quantitative evaluation of the parameters that influence the availability of land for bioenergy production. Unlike previous studies, the work also considers food waste in projections, the degraded land area, in addition to parameters that are often disregarded by other authors, such as urban agriculture and the consumption of insect proteins. The projections were made for 3 different scenarios: business as usual (C1), the best of realistic scenarios (C2), and the theoretical situation (C3). The projections disregard the economic and market influences that govern the distribution and use of land. The current excessive consumption and the impacts of human activities are responsible for the reduction in the available land area for bioenergy, while the application of disruptive technologies is the main factor of increase. There will be enough arable land to feed the world population in 2050 in the three proposed scenarios. However, even choosing to prioritize the preservation of forests, and going to shrubland as the next agricultural frontier, the arable land available for new bioenergy projects could be limited in C1, and it would be necessary to deforest 24% of the forests area (935 Mha). In C2, 5,7% of arable land would remain available to produce bioenergy, reaching 92% of the carbon sequestration target. And in C3, 42% of arable land could produce bioenergy to sequester more than 6 times the amount of carbon stipulated for 2100. The parameters with the greatest opportunities for gains, for quantitative reasons and technical feasibility of action, are food waste, low productivity due to land degradation, increases in productivity due to technological gain, and reduction in the consumption of animal proteins, especially from roaring animals. The potential participation of bioenergy in the global energy matrix is relevant even for C1, at 7.5%, with 64 EJ. In the best of realistic scenarios, C2, bioenergy could represent 21.0% of global energy production, with 178 EJ, while the energy crops could produce 31 times bigger than today. The results of the global bioenergy potential obtained in the projections of the most realistic scenarios, C1 and C2, were close to each other and other studies in the bibliography. In the theoretical situation, C3, bioenergy could supply almost two and a half times the total global demand for primary energy in 2050.