Comparative life cycle assessment of bio-based insulation materials: Environmental and economic performances

Insulation materials decrease the final energy consumption of buildings. In Germany, fossil and mineral insulations dominate the market despite numerous life cycle assessments (LCAs) showing that bio-based insulations can offer environmental benefits. Evaluating the results of such LCAs is, however, complex due to a lack of comparability or costs considered. The objective of this study is comparing bio-based insulations under equal conditions to identify the most environmentally friendly and cost-efficient material. For this purpose, a comparative LCA and life cycle costing (LCC) were conducted from "cradle to grave" for four bio-based and two nonrenewable insulations. The bio-based insulation materials evaluated were wood fiber, hemp fiber, flax, and miscanthus. The nonrenewable insulations were expanded polystyrene (EPS) and stone wool. Key data for the LCA of the bio-based insulations were obtained from preceding thermal conductivity measurements under ceteris paribus conditions. Eighteen environmental impact categories were assessed, and direct costs were cumulated along the life cycle. Results show that the most environmentally friendly bio-based insulation materials were wood fiber and miscanthus. A hotspot analysis found that, for agriculturally sourced insulations, cultivation had the largest environmental impact, and for wood fiber insulation, it was manufacturing. The use phase (including installation) constituted a cost hotspot. The environmental impacts of end-of-life incineration were strongly influenced by the fossil components of the materials. Overall, bio-based insulations were more environmentally friendly than EPS and stone wool in 11 impact categories. The LCC found EPS and miscanthus insulation to be most cost-efficient, yet market integration of the latter is still limited. It can be concluded that miscanthus biomass is an environmentally and economically promising bio-based insulation material. Comparability of the environmental performance of the bio-based insulations was increased by applying the same system boundary and functional unit, the same impact assessment methodology, and the preceding ceteris paribus thermal conductivity measurements

Nordic forest management towards climate change mitigation: time dynamic temperature change impacts of wood product systems including substitution effects

Climate change mitigation trade-offs between increasing harvests to exploit substitution effects versus accumulating forest carbon sequestration complicate recommendations for climate beneficial forest management. Here, a time dynamic assessment ascertains climate change mitigation potential from different rotation forest management alternatives across three Swedish regions integrating the forest decision support system Heureka RegWise with a wood product model using life cycle assessment data. The objective is to increase understanding on the climate effects of varying the forest management. Across all regions, prolonging rotations by 20% leads on average to the largest additional net climate benefit until 2050 in both, saved emissions and temperature cooling, while decreasing harvests by 20% leads to the cumulatively largest net climate benefits past 2050. In contrast, increasing harvests or decreasing the rotation period accordingly provokes temporally alternating net emissions, or slight net emission, respectively, regardless of a changing market displacement factor. However, future forest calamities might compromise potential additional temperature cooling from forests, while substitution effects, despite probable prospective decreases, require additional thorough and time explicit assessments, to provide more robust policy consultation

Climate change mitigation from increased paper recycling in Sweden: conserving forests or utilizing substitution?

Climate change mitigation by increased paper recycling can alleviate the two-sided pressure on the Swedish forest sector: supplying growing demands for wood-based products and increasing the forest carbon sink. This study assesses two scenarios for making use of a reduced demand for primary pulp resulting from an increased paper recycling rate in Sweden, from the present 72% to 78%. A Conservation scenario uses the saved primary pulp to reduce pulplog harvests so as to increase the forest carbon sink concomitant with constant overall wood product supply. In contrast, a Substitution scenario uses the saved primary pulp to produce man-made cellulosic fibers (MMCF) from dissolving pulp replacing cotton fiber, implying increased overall wood product supply. Our results suggest that utilizing efficiency gains in paper recycling to reduce pulplog harvests is better from a climate change mitigation perspective than producing additional MMCF to substitute cotton fiber. This conclusion holds even when assuming the use of by-products from dissolving pulp making and an indirect increase in MMCF availability. Hence, unless joint improvements across the value chain materialize, the best climate change mitigation option from increased paper recycling in Sweden would seemingly be to reduce fellings rather than producing additional MMCF

Demand-driven climate change mitigation and trade-offs from wood product substitution: The case of Swedish multi-family housing construction

Multi-family housing construction (MFHC) with wood instead of concrete as frame material results in lower greenhouse gas emissions. Hence, substituting wood for concrete in MFHC in Sweden until 2030, and onwards to 2070, could be a promising climate change mitigation option. But to what extent, and how would it impact Sweden's forests? Here we assess climate and biodiversity implications - in terms of the area of old forest - of a completely wood-based future MFHC in Sweden. The wood required is assumed to be exclusively sourced as additional fellings in Swedish forests, thus carbon leakage from wood imports as well as displacement of other wood uses can be disregarded. Different types of timber frame systems and the role of varying future dwelling sizes are considered. We find that the wood needed for a complete substitution of concrete would result in very minor increases in harvests. We further register slight net additional climate change mitigation, irrespective of the wood construction system. There is a small tradeoff between climate change mitigation and biodiversity, as the area of old forest reduces slightly. The largest climate benefit, and lowest impact on Swedish forests, is provided when using timber-light frame combined with reduced dwelling size

Nordic forest management towards climate change mitigation: time dynamic temperature change impacts of wood product systems including substitution effects

Climate change mitigation trade-offs between increasing harvests to exploit substitution effects versus accumulating forest carbon sequestration complicate recommendations for climate beneficial forest management. Here, a time dynamic assessment ascertains climate change mitigation potential from different rotation forest management alternatives across three Swedish regions integrating the forest decision support system Heureka RegWise with a wood product model using life cycle assessment data. The objective is to increase understanding on the climate effects of varying the forest management. Across all regions, prolonging rotations by 20% leads on average to the largest additional net climate benefit until 2050 in both, saved emissions and temperature cooling, while decreasing harvests by 20% leads to the cumulatively largest net climate benefits past 2050. In contrast, increasing harvests or decreasing the rotation period accordingly provokes temporally alternating net emissions, or slight net emission, respectively, regardless of a changing market displacement factor. However, future forest calamities might compromise potential additional temperature cooling from forests, while substitution effects, despite probable prospective decreases, require additional thorough and time explicit assessments, to provide more robust policy consultation

Identification of Neural Mechanisms in First Single-Sweep Analysis in oVEMPs and Novel Normative Data

Background: Bone-conducted (BC) VEMPs provide important tools for measuring otolith function. However, two major drawbacks of this method are encountered in clinical practice—small n10 amplitude and averaging technique. In this study, we present the results of a new VEMP setup measuring technique combined with a novel single-sweep analysis. Methods: The study included BC oVEMP data from 92 participants for the evaluation of normative data using a novel analysis technique. For evaluating test-retest reliability, the intraclass correlation coefficient (ICC) was used. Results: We found significant n10 amplitude differences in single-sweep analyses after the first and second measurements. Thereby, mathematical analyses of the head movement did not show any differences in the first or second measurements. The normative n10 amplitude was 20.66 µV with an asymmetric ratio (AR) of 7%. The new value of late shift difference (LSD) was 0.01 ms. The test retest-reliability showed good to excellent ICC results in 9 out of 10 measurements. Conclusions: Our results support a phenomenon in single-sweep analysis of the first stimuli independent of head movement and signal morphology. Furthermore, the values obtained with the new measurement method appear to be more sensitive and may allow an extended diagnostic range due to the new parameter LSD

Cross-Linguistic Interplay of Lexical Aspect and (Non-)Literalness

This contribution studies correlations between the degree of literalness and the syntax and semantics of French and German verbs. Annotation tests for sentences with German verbs with and without particles and their French equivalents provide evidence for a correlation between particle verbs and non-literal senses, and, for French verbs more than for German verbs, between a shift from literal to non-literal use and a shift in lexical aspect. The last section proposes a preliminary theoretical account for the empirical findings based on specific components and properties of events