Agricultural crops are worldwide seen as an alternative resource of energy and as raw materials for industrial processes (e.g. in the production of starch products and bioplastic, “second-generation products”). Increasing prices for traditional raw materials and primary energy resources as well as environmental concerns and consequently, political decisions pushed research initiatives on this topic.

Soils as the primary resource for the production of these renewable forms of energy are not renewable which implies the need of sustainable management. Fertilization and potential greenhouse gas emissions, water management (irrigation) and other ecological concerns (e.g. biodiversity) have to be considered. Concepts such as (virtual) water or carbon footprint assessment could deliver a wider understanding of the potential impacts. A sustainable efficiency enhancement is inevitable, in particular in developing countries, as the potential to convert additional land for agriculture is limited.

The first generation biofuels (bioethanol and biodiesel) are in direct competition to traditional food crops and in order to feed the world’s population in future, there is common agreement that this could be only a temporary solution on the way to the second-generation fuels, utilizing agricultural waste- and by-products as well as woody biomass from short-rotation woody crops (SRWC). Currently, feedstock from SRWC is mainly used for conversion into thermal energy and in case of combined heat and power plants (CHP) also into electrical energy.

Biogas production is another way to convert biomass to energy. Also in this case the digestion of agricultural and industrial residual products and waste should be preferred. Future biogas plants have to be designed to utilize also thermal energy as a by-product of power generation. Alternatively, technologies to upgrade biogas to fuel quality (biomethane) for injecting into the natural gas grid could result in a more efficient energy use.

Digestate storage, transport and application as fertilizer can have relevant ecological impacts on soil properties and ground water quality. Careful handling should be considered to minimize the emission of green house gases (GHG, e.g. nitrous oxide, methane).

The assessment of the emissions of GHG from biogas plants may be based on theoretical considerations but also on real on-site measurements with non-intererecing methods (such as long-path technologies).

Hot spots for biogas technology and the potential of feedstock shall be assessed based on economic and geographic considerations. GIS-based information technology may help to re-consider regional developments and to identify new regions for the implementation and application of biogas technology.

This session aims at assessing the potential of agricultural feedstock, residues of various origins and waste as raw materials for industrial processes and energy, the ecological consequences and to highlight perspectives to increase efficiency and sustainability.