In this paper a new input-output database is utilized to investigate the intermediate energy consumptions of the Italian economic sectors. we estimate an econometric model, which uses the assumption of homothetic separability, to confirm the results of a descriptive analysis of the energy-coefficient dynamics. The functional form adopted in the work is the Leontief-Diewert cost functions. The estimates are obtained by means of an Error Correction Model. Some conclusions about the characteristics of the different sectors and the trends in the utilization of the various energy types are pointed out. It appears that the unsatisfactory performance of the Italian economy (with respect to other OECD economies) can be interpreted in terms of both low reaction velocity to relative price changes and lack of autonomous energy savings in non-manufacturing sectors. Moreover, it is stressed that electric power penetration cannot be properly explained by interenergy substitutions, as electricity proves typically to be complementary to the remaining inputs.