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Although biofuels have the potential for mitigating climate change and enhancing energy security, controversy regarding their overall environmental sustainability is considered a significant bottleneck in their development at both global and EU levels. Life Cycle Assessment (LCA) was applied to model the current and prospective environmental profiles for poplar-derived bioethanol across various potential EU supply chains (different poplar plantation management, different pretreatment technologies for bioethanol production, five EU locations). LCA modelling indicated that E100 (100% bioethanol) and E85 (85% bioethanol, 15% petrol) fuels derived from Poplar from various locations in the EU had environmental impact scores some 10% to 90% lower than petrol in global warming potential, abiotic depletion potential, ozone depletion potential and photochemical oxidation potential depending upon the exact poplar supply chain and conversion technology modelled. Hybrid poplar clones with higher biomass yields, modified composition and improved cell wall accessibility had a clear potential to deliver a more environmentally sustainable lignocellulosic biorefining industry with environmental scores some 50% lower than with conventional poplar feedstocks. A particular aspect of the present study that warrants further research is the contribution that soil carbon accumulation can make to achieving low-GHG fuels in the future

Purpose Despite advances in the development of impact categories for ionising radiation, the focus on artificial radionuclides produced in the nuclear fuel cycle means that the potential impacts resulting from increased exposure to naturally occurring radioactive materials (NORM) are still only covered to a limited degree in life cycle assessment (LCA). Here, we present a potential framework for the inclusion of the exposure routes and impact pathways particular to NORM in LCA. Methods We assess the potential magnitude of enhanced NORM exposure, particularly in light of the potential use of NORM residues in building materials, and set out the potential exposure routes that may exist. We then assess the current state of the art, in terms of available fate, exposure and damage models, both within and outside of the LCA sphere. Finally, these exposure routes and modelling techniques are combined in order to lay out a potential framework for NORM assessment in LCA, both in terms of impact on humans and ecosystems. Results and discussion Increased exposure to NORM radionuclides can result either from their release to the environment or their proximity to humans as they reside in stockpiles, landfills or products. The exposure route via products is considered to be increasingly significant in light of current attempts to incorporate technologically enhanced NORMs (TENORM) including bauxite residue into building materials, by groups such as the ETN-MSCA REDMUD project. Impact assessment models for NORM exposure are therefore required to avoid potential burden shifting in the assessment of such TENORM products. Models describing the fate of environmental releases, the exhalation of radon from building products and the shielding effects on landfills/stockpiles are required to assess potential exposure. Subsequently, models relating exposure to radiation sources and the effective internal and external dose received by receptors are required. Finally, an assessment of the damage caused to the receptors is desirable. Conclusions A sufficient suite of currently existing and internationally recognised models exist that can, with varying degrees of modification, form the building blocks of a comprehensive NORM characterisation method for LCA. The challenge ahead lies in consolidating these models, from disparate fields, into a coherent and generally applicable method for the assessment of enhanced NORM exposure in LCA.

While it may be impossible to accurately predict what the world will look like in the future, we can be certain that it will be different from the world of today. By extension, we know that using today's data in life cycle assessment (LCA) studies claiming to represent future scenarios is problematic. For the future impact of products to be estimated in a consistent and meaningful manner in LCA, the background system, most commonly the ecoinvent database, needs to be projected into the future alongside the foreground system modeled in a given study. Futura is a new piece of open‐source software which allows LCA practitioners to create and share novel background databases representing arbitrary scenarios. It allows users to import a base database and then start making targeted changes. These changes take three main forms—adding new technologies, regionalizing new or existing technologies, and altering market compositions. All changes made are automatically added to a "recipe." This recipe file can be shared publicly. This recipe can be imported by other users and used to exactly recreate the modified database. The additive and transparent nature of this system means that initially simple scenarios can be built upon by others to progress toward more comprehensive scenarios in a stepwise manner. The inability to build on the work of others is a serious barrier to the progress of the LCA field. Futura goes some way to reduce this barrier in the field of prospective LCA.