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Item type:Publication, Access status: without files , Evaluating the absolute eco-efficiency of food products: A case study of rice in PakistanEco-efficiency is a quantitative management tool that has widely been used to evaluate the life cycle impacts of a product system along with its value to the stakeholders. However, the existing eco-efficiency assessment approaches are relative in nature and unable to address the growing environmental challenges. Therefore, this study is aimed at developing a novel approach using absolute eco-efficiency based on the absolute sustainability concept which attempts to align the environmental impacts with the Earth's carrying capacity. An absolute eco-efficiency framework is developed based on the planetary boundary-based life cycle assessment and calorific intake considering the healthy diet reference. A case study from food sector is considered because food production is already putting enormous pressure on ecosystems. All the analyzed scenarios of rice production in Pakistan could not meet the reference eco-efficiency targets for most of the environmental impact categories. Therefore, it was inferred that the consumption and production of rice in Pakistan is contributing to an increase in the triple planetary crisis, viz., global warming, biodiversity loss, and unsustainable use of one of the scarce resources. Recommendations were made to reduce the environmental impacts of rice within limits as well as to analyze the other food products and management practices to promote the sustainable foods and to avoid the unnecessary exploitation of resources.Publicationtype: Journal Article35 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: with files , Assessment of critical resource use in aircraft manufacturing(Springer, 2022-03-01); ; ; ; The global aircraft fleet has been expanding worldwide, leading to a high demand for primary resources. Simultaneously, recycling initiatives for decommissioned aircraft are still incipient. Following circular economy principles, the aims of this paper are to identify potentially critical resources used and related environmental impacts, to derive recommendations regarding recycling, and to analyze the influence of increasing utilization of lightweight composite materials in aircraft manufacturing. It was identified that the engine is the structure containing resources with the highest scarcity, with tantalum dominating seven of the eleven analyzed impact categories. Aluminum, titanium, and nickel were shown to lead to the highest environmental impacts. Hotspots in the criticality and environmental assessment often occur due to alloying resources with a low mass share. It was shown that aluminum and steel alloy recycling should be prioritized. A higher lightweight composite material share in the aircraft increases impacts in the categories climate change and fossil resource depletion by 12% and 20%, respectively, whereas the impact of the category acidification, political stability, and demand growth decreases by 16%, 35%, and 60%, respectively.Publicationtype: Journal ArticleScopus© Citations 6 111 302 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: with files , Hydrogen and hydrogen-derived fuels through methane decomposition of natural gas – GHG emissions and costsHydrogen can be produced from the decomposition of methane (also called pyrolysis). Many studies assume that this process emits few greenhouse gas (GHG) because the reaction from methane to hydrogen yields only solid carbon and no CO2. This paper assesses the life-cycle GHG emissions and the levelized costs for hydrogen provision from methane decomposition in three configurations (plasma, molten metal, and thermal gas). The results of these configurations are then compared to electrolysis and steam methane reforming (SMR) with and without CO2 capture and storage (CCS). Under the global natural gas supply chain conditions, hydrogen from methane decomposition still causes significant GHG emissions between 43 and 97 g CO2-eq./MJ. The bandwidth is predominately determined by the energy source providing the process heat, i.e. the lowest emissions are caused by the plasma system using renewable electricity. This configuration shows lower GHG emissions compared to the “classical” SMR (99 g CO2-eq./MJ) but similar emissions to the SMR with CCS (46 g CO2-eq./MJ). However, only electrolysis powered with renewable electricity leads to very low GHG emissions (3 g CO2-eq./MJ). Overall, the natural gas supply is a decisive factor in determining GHG emissions. A natural gas supply with below-global average GHG emissions can lead to lower GHG emissions of all methane decomposition configurations compared to SMR. Methane decomposition systems (1.6 to 2.2 €/kg H2) produce hydrogen at costs substantially higher compared to SMR (1.0 to 1.2 €/kg) but lower than electrolyser (2.5 to 3.0 €/kg). SMR with CCS has the lowest CO2 abatement costs (24 €/t CO2-eq., other > 141 €/t CO2-eq.). Finally, fuels derived from different hydrogen supply options are assessed. Substantially lower GHG emissions, compared to the fossil reference (natural gas and diesel/gasoline), are only possible if hydrogen from electrolysis powered by renewable energy is used (>90% less). The other hydrogen pathways cause only slightly lower or even higher GHG emissions.Publicationtype: Journal ArticleScopus© Citations 102 363 1134 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: with files , A review of life cycle assessment studies of electric vehicles with a focus on resource use(Multidisciplinary Digital Publishing Institute (MDPI), 2020-03-13); ; ; ; Changes in the mobility patterns have evoked concerns about the future availability of certain raw materials necessary to produce alternative drivetrains and related batteries. The goal of this article is to determine if resource use aspects are adequately reflected within life cycle assessment (LCA) case studies of electric vehicles (EV). Overall, 103 LCA studies on electric vehicles from 2009 to 2018 are evaluated regarding their objective, scope, considered impact categories, and assessment methods—with a focus on resource depletion and criticality. The performed analysis shows that only 24 out of 76 EV LCA and 10 out of 27 battery LCA address the issue of resources. The majority of the studies apply one of these methods: CML-IA, ReCiPe, or Eco-Indicator 99. In most studies, EV show higher results for mineral and metal resource depletion than internal combustion engine vehicles (ICEV). The batteries analysis shows that lithium, manganese, copper, and nickel are responsible for the highest burdens. Only few publications approach resource criticality. Although this topic is a serious concern for future mobility, it is currently not comprehensively and consistently considered within LCA studies of electric vehicles. Criticality should be included in the analyses in order to derive results on the potential risks associated with certain resources.Publicationtype: Journal ArticleScopus© Citations 47 262 763 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: with files , Renewable electricity targets in selected MENA countries – Assessment of available resources, generation costs and GHG emissions(Elsevier, 2019-10-25); ; ; MENA countries published national policy targets for the implementation of electricity from renewable energy (RE). These targets are important as they serve as framework for stakeholders in the energy sector like businesses and administration, while also showing governmental ambitions to the public. This paper investigates the impact on resources, generation cost and GHG emissions if the targets are met. It also examines whether the current development is achieving the targets and how the targets perform in the light of the Paris Agreement. 13 to 52 % of electricity from RE is targeted for 2030. The necessary RE expansion exceeds the current expansion in most countries. Only in Morocco and Jordan are projects indicating that the targets might be reached. From a resource perspective, a much stronger expansion is possible. Beneficial locations exist allowing to cover the domestic demand or even an export of electrical energy or derived energy carrier. Furthermore, especially PV, but also wind systems, can generate electricity in many areas for lower cost than fossil fuel fired power plants. Specific GHG emissions of national electricity production in 2017 are estimated to 396–682 gCO2e/kWh and decrease to 341–514 gCO2e/kWh if the 2030 RE targets are met. The type of fossil fuel has a strong impact on the GHG emissions. Although Morocco has highest RE deployment today and targets highest RE share in 2030, it shows today and in 2030 specific GHG emissions that are among the highest of considered MENA countries because electricity production from coal dominates whereas other countries use mainly natural gas. Existing policy targets decrease specific GHG emissions until 2030. However, stronger GHG mitigation efforts will be necessary afterwards in order to reach targets of the Paris Agreement. More ambitious 2030 policy target would distribute the load more evenly over time and should be reconsidered.Publicationtype: Journal ArticleScopus© Citations 32 420 407