22 research outputs found
Resource Footprints are Good Proxies of Environmental Damage
Environmental footprints are increasingly used to quantify and compare environmental impacts of for example products, technologies, households, or nations. This has resulted in a multitude of footprint indicators, ranging from relatively simple measures of resource use (water, energy, materials) to integrated measures of eventual damage (for example, extinction of species). Yet, the possible redundancies among these different footprints have not yet been quantified. This paper analyzes the relationships between two comprehensive damage footprints and four resource footprints associated with 976 products. The resource footprints accounted for >90% of the variation in the damage footprints. Human health damage was primarily associated with the energy footprint, via emissions resulting from fossil fuel combustion. Biodiversity damage was mainly related to the energy and land footprints, the latter being mainly determined by agriculture and forestry. Our results indicate that relatively simple resource footprints are highly representative of damage to human health and biodiversity
Biomass residues as twenty-first century bioenergy feedstockâa comparison of eight integrated assessment models
In the twenty-first century, modern bioenergy could become one of the largest sources of energy, partially replacing fossil fuels and contributing to climate change mitigation. Agricultural and forestry biomass residues form an inexpensive bioenergy feedstock with low greenhouse gas (GHG) emissions, if harvested sustainably. We analysed quantities of biomass residues supplied for energy and their sensitivities in harmonised bioenergy demand scenarios across eight integrated assessment models (IAMs) and compared them with literature-estimated residue availability. IAM results vary substantially, at both global and regional scales, but suggest that residues could meet 7â50% of bioenergy demand towards 2050, and 2â30% towards 2100, in a scenario with 300 EJ/year of exogenous bioenergy demand towards 2100. When considering mean literature-estimated availability, residues could provide around 55 EJ/year by 2050. Inter-model differences primarily arise from model structure, assumptions, and the representation of agriculture and forestry. Despite these differences, drivers of residues supplied and underlying cost dynamics are largely similar across models. Higher bioenergy demand or biomass prices increase the quantity of residues supplied for energy, though their effects level off as residues become depleted. GHG emission pricing and land protection can increase the costs of using land for lignocellulosic bioenergy crop cultivation, which increases residue use at the expense of lignocellulosic bioenergy crops. In most IAMs and scenarios, supplied residues in 2050 are within literature-estimated residue availability, but outliers and sustainability concerns warrant further exploration. We conclude that residues can cost-competitively play an important role in the twenty-first century bioenergy supply, though uncertainties remain concerning (regional) forestry and agricultural production and resulting residue supply potentials. © 2019, The Author(s)
LCâIMPACT: A regionalized life cycle damage assessment method
Life cycle impact assessment (LCIA) is a lively field of research, and data and models are continuously improved in terms of impact pathways covered, reliability, and spatial detail. However, many of these advancements are scattered throughout the scientific literature, making it difficult for practitioners to apply the new models. Here, we present the LCâIMPACT method that provides characterization factors at the damage level for 11 impact categories related to three areas of protection (human health, ecosystem quality, natural resources). Human health damage is quantified as disability adjusted life years, damage to ecosystem quality as global species extinction equivalents (based on potentially disappeared fraction of species), and damage to mineral resources as kilogram of extra ore extracted. Seven of the impact categories include spatial differentiation at various levels of spatial scale. The influence of value choices related to the time horizon and the level of scientific evidence of the impacts considered is quantified with four distinct sets of characterization factors. We demonstrate the applicability of the proposed method with an illustrative life cycle assessment example of different fuel options in Europe (petrol or biofuel). Differences between generic and regionalized impacts vary up to two orders of magnitude for some of the selected impact categories, highlighting the importance of spatial detail in LCIA. This article met the requirements for a gold â gold JIE data openness badge described at http://jie.click/badges.info:eu-repo/semantics/publishedVersio
The importance of biogenic carbon storage in the greenhouse gas footprint of medium density fiberboard from poplar wood and bagasse
Carbon storage in long-lived bio-based products is typically ignored or accounted for in a simplistic way in greenhouse gas (GHG) footprint calculations. We quantified the GHG footprint of medium density fiberboard (MDF) in Iran from poplar wood and bagasse, a by-product from sugarcane production. Inventory data was collected from sugarcane and poplar wood plantations and MDF factories in Iran during 2017â2019 to calculate cradle-to-grave footprints for 1 âm3 of MDF. We quantify the effect of carbon storage, which depends on the crop rotation time and the economic lifetime of the product, with shorter rotation times and longer storage periods leading to lower footprints. Cradle-to-grave GHG footprints of poplar and bagasse-based MDF without accounting for biogenic carbon storage are 6.8·102 âkg CO2-eq/m3 and 8.5·102 âkg CO2-eq/m3, respectively. Footprints are higher for bagasse-based MDF than for poplar-based MDF because of a higher electricity use, higher resin use and larger transport distances in Iran. Taking into account carbon storage periods of 10â60 years decreases the footprints to 345â655 âkg CO2-eq/m3 for poplar-based MDF and 292â771 âkg CO2-eq/m3 for bagasse-based MDF. These results emphasize the importance of appropriately accounting for biogenic carbon storage in GHG footprint calculations of long-lived bio based products
Potential carbon footprint reduction for reclaimed asphalt pavement innovations : Lca methodology, best available technology, and near-future reduction potential
The carbon footprints of asphalt mixtures with increasing reclaimed asphalt pavement (RAP) content were estimated using a life-cycle assessment methodology. Three asphalt mixtures with different applications and technical requirements, namely porous asphalt (PA), stone mastic asphalt (SMA), and asphalt concrete (AC), were included. The technology leaps needed to achieve asphalt mixtures containing up to 93% RAP were modelled. Mixtures containing up to 57% RAP were hot-mix asphalts (175 °C), while mixtures containing more RAP were produced at 135 °C and 105 °C. The energy requirements and their respective carbon footprints were calculated based on the heat capacity of the aggregates, RAP, and other bituminous materials. Furthermore, the effects of changing the countryâs electricity mix were also evaluated. A potential carbon footprint reduction of between 55% and 64% was found for one tonne of asphalt containing 93% RAP and produced at 105 °C compared to the 0% RAP mixture produced at 175 °C. Considering the uncertainty of this technology at its early stage of development, the reduction could be as low as 45% or as high as 79%. Changing the electricity mix to one that is likely to be implemented until 2030 in the Netherlands further reduces the footprint by 10%.</p
Global relative species loss due to first generation biofuel production for the transport sector
The global demand for biofuels in the transport sector may lead to significant biodiversity impacts via multiple human pressures. Biodiversity assessments of biofuels, however, seldom simultaneously address several impact pathways, which can lead to biased comparisons with fossil fuels. The goal of the present study was to quantify the direct influence of habitat loss, water consumption and greenhouse gas (GHG) emissions on potential global species richness loss due to the current production of firstâgeneration biodiesel from soybean and rapeseed and bioethanol from sugarcane and corn. We found that the global relative species loss due to biofuel production exceeded that of fossil petrol and diesel production in more than 90% of the locations considered. Habitat loss was the dominating stressor with Chinese corn, Brazilian soybean and Brazilian sugarcane having a particularly large biodiversity impact. Spatial variation within countries was high, with 90th percentiles differing by a factor of 9 to 22 between locations. We conclude that displacing fossil fuels with firstâgeneration biofuels will likely negatively affect global biodiversity, no matter which feedstock is used or where it is produced. Environmental policy may therefore focus on the introduction of other renewable options in the transport sector.JRC.D.5-Food Securit
Comparative Greenhouse Gas Footprinting of Online versus Traditional Shopping for Fast-Moving Consumer Goods : A Stochastic Approach
Variability in consumer practices and choices is typically not addressed in comparisons of environmental impacts of traditional shopping and e-commerce. Here, we developed a stochastic model to quantify the variability in the greenhouse gas (GHG) footprints of product distribution and purchase of fast-moving consumer goods (FMCGs) via three prevalent retail channels in the United Kingdom (U.K.). We found that shopping via bricks and clicks (click and fulfillment via physical store delivery) most likely decreases the GHG footprints when substituting traditional shopping, while FMCGs purchased through pure players with parcel delivery often have higher GHG footprints compared to those purchased via traditional retail. The number of items purchased and the last-mile travel distance are the dominant contributors to the variability in the GHG footprints of all three retail channels. We further showed that substituting delivery vans with electric cargo bikes can lead to a GHG emission reduction of 26% via parcel delivery. Finally, we showed the differences in the "last mile" GHG footprint of traditional shopping in the U.K. compared to three other countries (China, Netherlands, and the United States), which are primarily caused by the different shares of modes of transport (walking and by car, bus, and bike).</p
Global implications of crop-based bioenergy with carbon capture and storage for terrestrial vertebrate biodiversity
Bioenergy with carbon capture and storage (BECCS) based on purposeâgrown lignocellulosic crops can provide negative CO(2) emissions to mitigate climate change, but its land requirements present a threat to biodiversity. Here, we analyse the implications of cropâbased BECCS for global terrestrial vertebrate species richness, considering both the landâuse change (LUC) required for BECCS and the climate change prevented by BECCS. LUC impacts are determined using globalâequivalent, speciesâarea relationshipâbased loss factors. We find that sequestering 0.5â5 Gtonne of CO(2) per year with lignocellulosic cropâbased BECCS would require hundreds of Mha of land, and commit tens of terrestrial vertebrate species to extinction. Species loss per unit of negative emissions decreases with: (i) longer lifetimes of BECCS systems, (ii) less overall deployment of cropâbased BECCS and (iii) optimal land allocation, that is prioritizing locations with the lowest species loss per negative emission potential, rather than minimizing overall land use or prioritizing locations with the lowest biodiversity. The consequences of prevented climate change for biodiversity are based on existing climate response relationships. Our tentative comparison shows that for cropâbased BECCS considered over 30Â years, LUC impacts on vertebrate species richness may outweigh the positive effects of prevented climate change. Conversely, for BECCS considered over 80Â years, the positive effects of climate change mitigation on biodiversity may outweigh the negative effects of LUC. However, both effects and their interaction are highly uncertain and require further understanding, along with the analysis of additional species groups and biodiversity metrics. We conclude that factoring in biodiversity means lignocellulosic cropâbased BECCS should be used early to achieve the required mitigation over longer time periods, on optimal biomass cultivation locations, and most importantly, as little as possible where conversion of natural land is involved, looking instead to sustainably grown or residual biomassâbased feedstocks and alternative strategies for carbon dioxide removal
Biomass residues as twenty-first century bioenergy feedstockâa comparison of eight integrated assessment models
In the twenty-first century, modern bioenergy could become one of the largest sources of energy, partially replacing fossil fuels and contributing to climate change mitigation. Agricultural and forestry biomass residues form an inexpensive bioenergy feedstock with low greenhouse gas (GHG) emissions, if harvested sustainably. We analysed quantities of biomass residues supplied for energy and their sensitivities in harmonised bioenergy demand scenarios across eight integrated assessment models (IAMs) and compared them with literature-estimated residue availability. IAM results vary substantially, at both global and regional scales, but suggest that residues could meet 7â50% of bioenergy demand towards 2050, and 2â30% towards 2100, in a scenario with 300 EJ/year of exogenous bioenergy demand towards 2100. When considering mean literature-estimated availability, residues could provide around 55 EJ/year by 2050. Inter-model differences primarily arise from model structure, assumptions, and the representation of agriculture and forestry. Despite these differences, drivers of residues supplied and underlying cost dynamics are largely similar across models. Higher bioenergy demand or biomass prices increase the quantity of residues supplied for energy, though their effects level off as residues become depleted. GHG emission pricing and land protection can increase the costs of using land for lignocellulosic bioenergy crop cultivation, which increases residue use at the expense of lignocellulosic bioenergy crops. In most IAMs and scenarios, supplied residues in 2050 are within literature-estimated residue availability, but outliers and sustainability concerns warrant further exploration. We conclude that residues can cost-competitively play an important role in the twenty-first century bioenergy supply, though uncertainties remain concerning (regional) forestry and agricultural production and resulting residue supply potentials