Towards a low CO2 emission building material employing bacterial metabolism (2/2): Prospects for global warming potential reduction in the concrete industry.

The production of concrete is one of the most significant contributors to global greenhouse gas emissions. This work focuses on bio-cementation-based products and their potential to reduce global warming potential (GWP). In particular, we address a proposed bio-cementation method employing bacterial metabolism in a two-step process of limestone dissolution and recrystallisation (BioZEment). A scenario-based techno-economic analysis (TEA) is combined with a life cycle assessment (LCA), a market model and a literature review of consumers' willingness to pay, to compute the expected reduction of global GWP. Based on the LCA, the GWP of 1 ton of BioZEment is found to be 70-83% lower than conventional concrete. In the TEA, three scenarios are investigated: brick, precast and onsite production. The results indicate that brick production may be the easiest way to implement the products, but that due to high cost, the impact on global GWP will be marginal. For precast production the expected 10% higher material cost of BioZEment only produces a marginal increase in total cost. Thus, precast production has the potential to reduce global GWP from concrete production by 0-20%. Significant technological hurdles remain before BioZEment-based products can be used in onsite construction scenarios, but in this scenario, the potential GWP reduction ranges from 1 to 26%. While the potential to reduce global GWP is substantial, significant efforts need to be made both in regard to public acceptance and production methods for this potential to be unlocked.

Food security and food insecurity in Europe: An analysis of the academic discourse (1975-2013).

In this paper we address the academic discourse on food insecurity and food security in Europe as expressed in articles published in scientific journals in the period 1975 to 2013. The analysis indicates that little knowledge has been produced on this subject, and that the limited research that has been produced tends to focus on the production of food rather than on people's access to food. The lack of knowledge about European food insecurity is particularly alarming in these times, which are characterised by increasing social inequalities and poverty, as well as shifting policy regimes. More empirical, comparative and longitudinal research is needed to survey the extent of food security problems across European countries over time. There is also a need to identify groups at risk of food insecurity as well as legal, economic, practical, social, and psychological constraints hindering access to appropriate and sufficient food.