In an increasingly urbanized world, the concepts of ecosystem services and nature-based solutions can help tackle grand challenges. However, ambiguity in their definitions and in the relationship... Show moreIn an increasingly urbanized world, the concepts of ecosystem services and nature-based solutions can help tackle grand challenges. However, ambiguity in their definitions and in the relationship between the two concepts complicates comprehensive research efforts as well as their effective application in policy and planning in urban systems. This paper presents a framework to clarify and explicitly relate the two concepts, enhancing their applicability in the management of urban challenges. Within the framework, addressing urban challenges serves as the starting point for the development and implementation of nature-based solutions. Nature-based solutions alter the flows of ecosystem services that are produced by an ecosystem by altering the performance of the ecosystem or by changing how people engage with the ecosystem. This results both in changes in the target ecosystem services, as well as non-targeted ecosystem services, leading to benefits. Using two illustrative case studies, we show how the framework can be applied to two urban challenges that are expected to increase in intensity in cities across the world: stormwater management and urban heat stress. Moreover, we highlight key research topics that will benefit from more integrated use of nature-based solutions and ecosystem services. The framework helps emphasize co-benefits, and can be used to help make co-benefits and multifunctionality explicit in urban decision-making and planning processes. Show less
Lack of knowledge and tools hampers circular transition in the construction industry. This study analyzes the potential of a framework of circular indicators put forward by the Building Research... Show moreLack of knowledge and tools hampers circular transition in the construction industry. This study analyzes the potential of a framework of circular indicators put forward by the Building Research Establishment Environmental Assessment Method (BREEAM-C) as an answer to the prevailing need of a metric for building circularity assessment to promote circular construction. A qualitative analysis approach is adopted, involving literature review, comparative case study and semi-structured interviews conducted for collecting expert opinions. An in-depth scrutiny of the BREEAM-C indicators revealed that they are rooted in circular principles, cover building circularity realizable through circular strategies, and have given due consideration to circularity in different impact areas, structural layers and life-cycle stages of buildings. Moreover, BREEAM-C indicators not only show capacity in identifying CE-related practices implemented, but also serve as benchmarks testifying that CE principles/strategies are incorporated in the design, construction, operation and management of the buildings. Despite having room for expansion, BREEAM-C has proven to be applicable and practical with potential for use in Taiwan as confirmed by expert opinions. Nevertheless, adaptation/localization is required to cater for different concerns with respect to climate and safety as well as local context and legislations. Show less
Proton exchange membrane (PEM) water electrolyzers are a promising technology for high-purity, efficient green hydrogen production, with expanding installations. This has increased demand for... Show moreProton exchange membrane (PEM) water electrolyzers are a promising technology for high-purity, efficient green hydrogen production, with expanding installations. This has increased demand for materials like platinum (Pt) used in PEM manufacturing. Conversely, Pt, which currently serves primarily as catalysts for internal combustion engine vehicles (ICEVs), would become available as ICEVs are phased out. Here, we simulate the Pt requirements for rapid scale-up PEM electrolyzers and quantitatively compare these requirements with the availability of Pt from scraped autocatalysts under the IEA-NZE scenario. Our results show that demand for Pt in PEM electrolyzers is expected to increase by an order of magnitude by 2050, while ICEVs are expected to cumulatively scrap ∼2500 tons of Pt. The Pt surplus from ICEVs would meet the increasing Pt demand for PEM eletrolyzers from 2030 onwards. These findings offer fresh insights into using the potential of urban mines to meet the energy transition challenges. Show less
III–V/Silicon tandem solar cells offer one of the most promising avenues for high-efficiency, high-stability photovoltaics. However, a key concern is the potential environmental release of group... Show moreIII–V/Silicon tandem solar cells offer one of the most promising avenues for high-efficiency, high-stability photovoltaics. However, a key concern is the potential environmental release of group III–V elements, especially arsenic. To inform long-term policies on the energy transition and energy security, we develop and implement a framework that fully integrates future PV demand scenarios with dynamic stock, emission, and fate models in a probabilistic ecological risk assessment. We examine three geographical scales: local (including a floating utility-scale PV and waste treatment), regional (city-wide), and continental (Europe). Our probabilistic assessment considers a wide range of possible values for over one hundred uncertain technical, environmental, and regulatory parameters. We find that III–V/silicon PV integration in energy grids at all scales presents low-to-negligible risks to soil and freshwater organisms. Risks are further abated if recycling of III–V materials is considered at the panels' end-of-life. Show less
Scenarios that limit global warming to 1.5°C rely on a combination of interventions to reduce greenhouse gas emissions and capture carbon dioxide. However, the extent to which lifestyle change... Show moreScenarios that limit global warming to 1.5°C rely on a combination of interventions to reduce greenhouse gas emissions and capture carbon dioxide. However, the extent to which lifestyle change contributes to mitigation relative to technological change over time remains understudied. Here, we present a scenario model that incorporates extensive supply-side technological transformations while excluding lifestyle changes. By adapting a global supply-use table from EXIOBASE using elements from Shared Socioeconomic Pathway 1 and a mitigation pathway consistent with the 1.5°C target, we assess how household footprints evolve in 2030 and 2050 and the extent to which technological change alone can mitigate greenhouse gas emissions. We modeled footprints for 49 countries/regions, with a focus on the EU27. Our scenario results indicate that while technological change can substantially reduce emissions, the reductions are ultimately insufficient to achieve the 1.5°C target. Eight EXIOBASE regions, including three EU27 countries, are on a 1.5°C-consistent trajectory with just technological advancements in 2030. However, by 2050, no countries are projected to meet the 1.5°C-compatible target. The average EU27 overshoot for household footprints approaches 2.2 tCO2e/cap in 2030 and 3.1 tCO2e/cap in 2050. Global overshoots are more moderate at 0.3 tCO2e/cap in 2030 and 2.0 tCO2e/cap in 2050. Our results highlight the critical role of household lifestyle transformation in climate change mitigation. Future research can explore the diverse lifestyle change pathways necessary to align with the aspirational 1.5°C target outlined in the Paris Agreement. Show less
The increase in food demand and limited opportunities to expand agricultural land pose a threat to local and global food security. Producing food in urban areas such as green roofs can help satisfy... Show moreThe increase in food demand and limited opportunities to expand agricultural land pose a threat to local and global food security. Producing food in urban areas such as green roofs can help satisfy urban food demand and thus alleviate pressure on agricultural land. However, a modeling framework that simulates crop growth and production potential on green roofs at a city scale is missing. Here, we adapt the Aquacrop model to explore the growth potential of various types of crops on green roofs and apply it to suitable roof areas in the city of Amsterdam. Our modeling framework includes irrigation methods for water use on green roofs that are optimized according to various climate-driven scenarios of water availability. We find that cabbage has the maximum achievable crop yields ranging from 30.8 to 75.9 t ha-1 yr-1, while pea has the minimum achievable crop yields ranging from 1.7 to 6.4 t ha-1 yr-1. The potential suitable green roof area (i.e., roofs with a certain slope and bearing capacity) for Amsterdam is roughly 400 ha for crop production. This represents 16 % of the total rooftop areas of Amsterdam and can produce up to a total of 28 kt of crops on an annual basis. Our modeling framework can be easily applied to other cities to identify the crop growth potential of green roofs. Our results can help policymakers and urban planners find optimal planting strategies and contribute to shorter food supply chains. Show less
Geukes, H.H.; Bodegom, P.M. van; Oudenhoven, A.P.E. van 2024
Nature-based solutions (NbS) are fast becoming the norm for multifunctional coastal climate adaptation to increased sea-level rise. However, informing decision-makers about NbS presents ongoing... Show moreNature-based solutions (NbS) are fast becoming the norm for multifunctional coastal climate adaptation to increased sea-level rise. However, informing decision-makers about NbS presents ongoing challenges. This study set out to identify and explore the information requirements at different stages of the decision-making process of coastal NbS. Developing and applying a novel methodological approach, we analysed the values and indicators discussed in four key decision-making stages: the advocacy, political, bureaucratic and provisioning stages. Applied to a mega beach nourishment in the Netherlands, our study identified substantial differences in information requirements across the decision-making stages. Most notably, the values and indicators discussed shifted from being abstract to becoming increasingly specific and concrete as the stages progressed. Our findings emphasize the importance of recognizing the distinct stages of decision-making and tailoring the content and level of abstraction of information accordingly. Additionally, they suggest that future changes in the content and concretisation of the information required for decision-making on coastal NbS can be anticipated and prepared for. By distinguishing and understanding the decision-making stages in NbS, this study bridges a longstanding gap between decision-making and NbS studies, thereby allowing for improving the fairness, implementation, evaluation and comprehension of trade-offs of coastal NbS. This study progresses the understanding of the information required for planning, implementing, evaluating and managing coastal NbS, advancing multifunctional coastal climate adaptation for shores worldwide. Show less
Musters, C.J.M.; Honkoop, H.P.; Snoo, G.R. de 2024
n decision making for insect conservation, one depends largely on knowledge of the relationship between changes in environmental factors and abundance of a very limited number of species. The... Show moren decision making for insect conservation, one depends largely on knowledge of the relationship between changes in environmental factors and abundance of a very limited number of species. The species we have knowledge on cannot be regarded as a representative sample of all insects. How accurately do changes in the abundance of these species predict the changes in other species? To answer this question, we studied 373 insect species belonging to the Apidae (bees), Lepidoptera (butterflies), Orthoptera (grasshoppers), Ephemeroptera (mayflies), Trichoptera (caddisflies), Odonata (dragonflies), and Plecoptera (stoneflies), with known population trends and attributes in the Netherlands. The 78 attributes included morphological and demographic trait values, as well as habitat requirements of species. We trained Random Forests (RFs) with random samples and with taxonomic groups to predict the decline of the species based on their attributes. Then we used the trained RFs to predict the decline of the species outside the training groups and checked the accuracy of the predictions. The results showed that accuracy of the predictions of the RFs trained by the random samples increased from 0 to 0.20 (maximum 0.40, on a scale of 0 to 1) with sample size increasing from 10 to 90% of the insects. Moreover, we found that the accuracy of the predictions by the RFs trained with the taxonomic groups were zero in case of butterflies and grasshoppers, and low in other groups (maximum 0.37, in case of bees predicting terrestrial insects). Accuracy depended significantly on the size of the taxonomic group. Large over- or underestimation of number of declining species occurred in all cases. Further, we found that the taxonomic groups had few attributes important for predicting in common. The attribute ‘Active dispersion’ had the highest importance when all insects were used for training the RF. Using ‘indicator groups’ for predicting the decline of insects has a high risk of over- or underestimating the actual number of declining species and should therefore be advised against unless the indicator group is sure to be representative. Show less
Sodium-ion batteries (SIBs) have emerged as an alternative to lithium-ion batteries (LIBs) due to their promising performance in terms of battery cycle lifetime, safety, operating in wider... Show moreSodium-ion batteries (SIBs) have emerged as an alternative to lithium-ion batteries (LIBs) due to their promising performance in terms of battery cycle lifetime, safety, operating in wider temperature range, as well as the abundant and low-cost of sodium resources. This study evaluated the climate impacts of three SIBs, and compared to two LIBs under four scenarios with considering potential changes in battery performance and background productions between 2020 and 2050. To ensure a fair comparison, all batteries were modeled in the 21,700 form, and a battery dimensioning model was developed to calculate the required amount of components for each battery. We found that equal to lower GHG emissions result from the use of SIBs compared to LIBs under optimal performance scenarios. From 2020 to 2050, the climate impacts of SIBs decreased by 43–57 %. The relative contribution of the battery manufacturing process decreases from 18–32 % to 2–4 % due to the increasingly share of clean energy in the electricity grid, while the relative contribution of key battery component materials increases over time, especially for cathode active materials. These results emphasize the significance of decarbonizing the electric grid, and suggest that future investment in SIBs is promising from an environmental point of view. Show less