"1st or 2nd generation bioethanol-impacts of technology integration & on feed production and land use"

Liquid bio fuels are perceived as a means of mitigating CO₂ emissions from transport and thus climate change, but much concern has been raised to the energy consumption from refining biomass to liquid fuels.

Integrating technologies such that waste stream can be used will reduce energy consumption in the production of bioethanol from wheat. We show that the integration of bio refining and combined heat an power generation reduces process energy requirements with 30-40 % and makes bioethanol production comparable to gasoline production in terms of energy loss.

Utilisation of biomass in the energy sector is inevitably linked to the utilisation of land. This is a key difference between fossil and bio based energy systems. Thus evaluations of bioethanol production based on energy balances alone are inadequate. 1st and 2nd generation bioethanol production exhibits major differences when evaluated on characteristics as feed energy and feed protein production and subsequently on land use changes.

1st generation bioethanol production based on wheat grain in Denmark may in fact reduce the pressure on agricultural land on a global scale, but increase the pressure on local/national scale. In contrast to that 2nd generation bioethanol based on wheat straw exhibits a poorer energy balance than 1st generation, but the induced imbalances on feed energy are smaller.

Proteins are some of the plant components with the poorest bio synthesis efficiency and as such the area demand for their production is relatively high. Preservation of the proteins in the biomass such as in feed by-products from bioethanol production is of paramount importance in developing sustainable utilisation of biomass in the energy sector.