Energy and CO2 analysis of poplar and maize crops for biomass production in north Italy

The rising price of fossil fuel and the increasing environmental concern encourage the use of biomasses as energy sources. Aim of this study was to compare two poplar SRC and vSRC (6 and 3 years rotation cycle) with an annual crop (maize), used for biomass production in North Italy. The average of the biomass production was 13.9 Mg DM ha−1 per year for the SRC and vSRC poplar and 19.2 Mg DM ha−1 for the maize. The energy consumption for the poplar cultivations was about 15 GJ ha−1 per year, which represented only the 6% of the energy biomass product (about 257 GJ ha−1 per year). The input value of the maize was higher (26.8 GJ ha−1 per year). In this case, the input value was about the 7% of the energy content in the biomass product (about 370 GJ ha−1 per year). During the vSRC cultivation an amount of 8090 kg CO2 eq ha−1 was emitted, 6420 kg CO2 eq ha−1 for the SRC and 26,370 kg CO2 eq ha−1 for the maize. Compared to the maize, the poplar SRC (or vSRC) crops are interesting from an energetic point of view, while maize requires less manpower, but it has major problems related to the landscape biodiversity.