Resumo. The objective of this work was to build a countercurrent gasifier in hardened mortar to evaluate the potential of generating electrical energy of eucalyptus species grown in the state of Minas Gerais, from agroindustry residues and from the mixture of those materials. The immediate chemical composition and the heat power of the materials utilized were determined. The different lignocellulosic materials were experienced, and gas was used as the control. For the factors being tested, measurements of the electric yields and consumptions of the materials were performed. The statistical design was the completely randomized with seventeen treatments and three replicates done at 5% of significance. On the basis of the results obtained and on the statistical analyses performed, it follows that the gasifier-generator set is easy to build, made with easily purchased and low cost materials. Among the materials evaluated the coal of the species, Corimbia citriodora, with 78% of fixed carbon, presented the best performance of generated power, obtaining 1,391 watts, with a constant tension of 230 volts. The residues utilized of cane bagasse, rice straw, corn cob, coffee husk and coal chaff presented no potential to generate energy by the sort of gasifier utilized.