Life Cycle Assessment of Closed-Loop Pumped Storage Hydropower in the United States

The United States has begun unprecedented efforts to decarbonize all sectors of the economy by 2050, requiring rapid deployment of variable renewable energy technologies and grid-scale energy storage. Pumped storage hydropower (PSH) is an established technology capable of providing grid-scale energy storage and grid resilience. There is limited information about the life cycle of greenhouse gas emissions associated with state-of-the-industry PSH technologies. The objective of this study is to perform a full life cycle assessment of new closed-loop PSH in the United States and assess the global warming potential (GWP) attributed to 1 kWh of stored electricity delivered to the nearest grid substation connection point. For this study, we use publicly available data from PSH facilities that are in the preliminary permitting phase. The modeling boundary is from facility construction to decommissioning. Our results estimate that the GWP of closed-loop PSH in the United States ranges from 58 to 530 g CO2e kWh-1, with the stored electricity grid mix having the largest impact, followed by concrete used in facility construction. Additionally, PSH site characteristics can have a substantive impact on GWP, with brownfield sites resulting in a 20% lower GWP compared to greenfield sites. Our results suggest that closed-loop PSH offers climate benefits over other energy storage technologies.

Life cycle thinking and safe-and-sustainable-by-design approaches for the battery innovation landscape

Developments in battery technology are essential for the energy transition and need to follow the framework for safe-and-sustainable-by-design (SSbD) materials, chemicals, products, and processes as set by the EU. SSbD is a broad approach that ensures that chemicals/advanced materials/products/services are produced and used in a way to avoid harm to humans and the environment. Technical and policy-related literature was surveyed for battery technologies and recommendations were provided for a broad SSbD approach that remains firmly grounded in Life Cycle Thinking principles. The approach integrates functional performance and sustainability (safety, social, environmental, and economic) aspects throughout the life cycle of materials, products, and processes, and evaluates how their interactions reflect on SSbD parameters. 22 different types of batteries were analyzed in a life cycle thinking approach for criticality, toxicity/safety, environmental and social impact, circularity, functionality, and cost to ensure battery innovation has a green and sustainable purpose to avoid unintended consequences.

Spatiotemporal analysis of the future carbon footprint of solar electricity in the United States by a dynamic life cycle assessment

Solar photovoltaics (PVs) installation would increase 20-fold by 2050; however, considerable greenhouse gas (GHG) emissions are generated during the cradle-to-gate production, with spatiotemporal variances depending on the grid emission. Thus, a dynamic life cycle assessment (LCA) model was developed to assess the accumulated PV panels with a heterogeneous carbon footprint if manufactured and installed in the United States. The state-level carbon footprint of solar electricity (CFE _PV-avg) from 2022 to 2050 was estimated using several cradle-to-gate production scenarios to account for emissions stemming from electricity generated from solar PVs. The CFE _PV-avg (min 0.032, max 0.051, weighted avg. 0.040 kg CO₂-eq/kWh) in 2050 will be significantly lower than that of the comparison benchmark (min 0.047, max 0.068, weighted avg. 0.056 kg CO₂-eq/kWh). The proposed dynamic LCA framework is promising for planning solar PV supply chains and, ultimately, the supply chain of an entire carbon-neutral energy system to maximize the environmental benefits.

Distributed desalination using solar energy: A technoeconomic framework to decarbonize nontraditional water treatment

Desalination using renewable energy offers a route to transform our incumbent linear consumption model to a circular one. This transition will also shift desalination from large-scale centralized coastal facilities toward modular distributed inland plants. This new scale of desalination can be satisfied using solar energy to decarbonize water production, but additional considerations, such as storage and inland brine management, become important. Here, we evaluate the levelized cost of water for 16 solar desalination system configurations at 2 different salinities. For fossil fuel-driven plants, we find that zero-liquid discharge is economically favorable to inland brine disposal. For renewable desalination, we discover that solar-thermal energy is superior to photovoltaics due to low thermal storage cost and that energy storage, despite being expensive, outperforms water storage as the latter has a low utilization factor. The analysis also yields a promising outlook for solar desalination by 2030 as solar generation and storage costs decrease.

Food, Energy, and Water Nexus at Household Level: Do Sustainable Household Consumption Practices Promote Cleaner Environment?

Governments around the globe are trying to find sustainable solutions for lessening pressure on natural resources and reducing carbon emissions. Daily household consumption of food, energy, and water has an impact on stocks of natural resources, environmental quality, and climate change. Households have significant potential for increasing conservation actions for efficient use of natural resources and greenhouse gas emissions. Households could contribute to a clean and healthy environment by adopting sustainable household practices through lower per capita consumption and carbon emissions. This study explored the role of different sustainable household consumption practices in promoting a clean environment as well as the factors affecting the adoption of these practices in Pakistan. Factor analysis and an ordered probit model were used to analyze the data from 1424 participants chosen through a multistage random sampling technique. The factor analysis identified 35 sustainable household practices for sustainable consumption. These 35 practices were grouped into the underlying factors of "Food" (14 items), "Energy" (12 items), and "Water" (9 items). The results from the econometric model showed a significant relationship between gender, education, residential area, family size, and income and the adoption of sustainable household consumption practices. Statistically, higher levels of reported sustainable consumption practices were apparent among females, households living in urban areas, more educated people, individuals of large family sizes, and more affluent households. Therefore, public policies for taking care of the environment need to put households at the center while at the same time promoting mass uptake of sustainable consumption practices related to food, energy, and water. In addition, the sector-specific policies also need to be augmented through focus on household-level consumption and production dynamics for achieving the UN's SDGs.

Emerging Trends in Sustainable CO2 -Management Materials

With the rising level of atmospheric CO₂ worsening climate change, a promising global movement toward carbon neutrality is forming. Sustainable CO₂ management based on carbon capture and utilization (CCU) has garnered considerable interest due to its critical role in resolving emission-control and energy-supply challenges. Here, a comprehensive review is presented that summarizes the state-of-the-art progress in developing promising materials for sustainable CO₂ management in terms of not only capture, catalytic conversion (thermochemistry, electrochemistry, photochemistry, and possible combinations), and direct utilization, but also emerging integrated capture and in situ conversion as well as artificial-intelligence-driven smart material study. In particular, insights that span multiple scopes of material research are offered, ranging from mechanistic comprehension of reactions, rational design and precise manipulation of key materials (e.g., carbon nanomaterials, metal-organic frameworks, covalent organic frameworks, zeolites, ionic liquids), to industrial implementation. This review concludes with a summary and new perspectives, especially from multiple aspects of society, which summarizes major difficulties and future potential for implementing advanced materials and technologies in sustainable CO₂ management. This work may serve as a guideline and road map for developing CCU material systems, benefiting both scientists and engineers working in this growing and potentially game-changing area.

How do China's lockdown and post-COVID-19 stimuli impact carbon emissions and economic output? Retrospective estimates and prospective trajectories

This paper develops a multi-sector and multi-factor structural gravity model that allows an analytical and quantitative decomposition of the emission and output changes into composition and technique effects. We find that the negative production shock of China's containment policy propagates globally via supply chains, with the carbon-intensive sectors experiencing the greatest carbon emission shocks. We further reveal that China's current stimulus package in 2021-2025 is consistent with China's emission intensity-reduction goals for 2025, but further efforts are required to meet China's carbon emissions-peaking target in 2030 and Cancun 2°C goal. Short-term changes in carbon emissions resulting from lockdowns and initial fiscal stimuli in "economic rescue" period have minor long-term effects, whereas the transitional direction of future fiscal stimulus exerts more predominant impact on long-term carbon emissions. The efficiency improvement effects are more important than the sectoral structure effects of the fiscal stimulus in achieving greener economic growth.

Food Practice Lifestyles: Identification and Implications for Energy Sustainability

Food systems, including production, acquisition, preparation, and consumption, feature importantly in environmental sustainability, energy consumption and climate change. With predicted increases in food and water shortages associated with climate change, food-related lifestyle and behavioral changes are advocated as important mitigation and adaptation measures. Yet, reducing emissions from food systems is predicted to be one of our greatest challenges now and in the future. Traditional theories of environmental behavioral change often assume that individuals make “reasoned choices” that incorporate cost–benefit assessment, moral and normative concerns and affect/symbolic motives, yielding behavioral interventions that are often designed as informational or structural strategies. In contrast, some researchers recommend moving toward an approach that systematically examines the temporal organization of society with an eye toward understanding the patterns of social practices to better understand behaviors and develop more targeted and effective interventions. Our study follows on these recommendations with a study of food consumption “lifestyles” in the United States, using extant time use diary data from a nationally representative sample of Americans (n = 16,100) from 2014 to 2016. We use cluster analysis to identify unique groups based on temporal and locational eating patterns. We find evidence of six respondent clusters with distinct patterns of food consumption based on timing and location of eating, as well as individual and household characteristics. Factors associated with cluster membership include age, employment status, and marital status. We note the close connections between age and behaviors, suggesting that a life course scholarship approach may add valuable insight. Based on our findings, we identify opportunities for promoting sustainable energy use in the context of the transition to renewables, such as targeting energy-shifting and efficiency-improvement interventions based on group membership.

Barriers to and uncertainties in understanding and quantifying global critical mineral and element supply

The critical minerals and elements are natural substances that are essential to modern life but have insecure supply. This lack of a secure supply clashes with the increasing importance of these elements, especially given their use in technologies needed to reduce global CO₂ emissions and mitigate against anthropogenic climate change. In this contribution we review the by-product nature of the critical minerals and elements and the inherant uncertainties in reported critical mineral and element annual production as well as the relationships between these commodities and main-product metals and associated concentrates. We explore the geological and geographical barriers to critical mineral and element supplies, as well as how the lack of available data and the uncertainties in the data that are available hinder our ability to estimate global resources with confidence.

Designing optimal integrated electricity supply configurations for renewable hydrogen generation in Australia

The high variability and intermittency of wind and solar farms raise questions of how to operate electrolyzers reliably, economically, and sustainably using predominantly or exclusively variable renewables. To address these questions, we develop a comprehensive cost framework that extends to include factors such as performance degradation, efficiency, financing rates, and indirect costs to assess the economics of 10 MW scale alkaline and proton-exchange membrane electrolyzers to generate hydrogen. Our scenario analysis explores a range of operational configurations, considering (i) current and projected wholesale electricity market data from the Australian National Electricity Market, (ii) existing solar/wind farm generation curves, and (iii) electrolyzer capital costs/performance to determine costs of H₂ production in the near (2020-2040) and long term (2030-2050). Furthermore, we analyze dedicated off-grid integrated electrolyzer plants as an alternate operating scenario, suggesting oversizing renewable nameplate capacity with respect to the electrolyzer to enhance operational capacity factors and achieving more economical electrolyzer operation.

Bio-Waste Thermal Insulation Panel for Sustainable Building Construction in Steady and Unsteady-State Conditions

Apart from being used as an oil stock for bio-fuels production, an annual crop plant Brassica napus, thought to be an agro-waste, and used either as an animal feed, soil fertilizer or biomass for combustion and thermal energy production. Alternatively, as a bio-based and locally bio-sourced cellulosic material, it could be used as a thermal insulation in sustainable building fabrication, likewise woodchips, a bio-waste from the wood industry. In this study, the above-mentioned bio-waste materials’ thermal properties were identified using a sandwich panel from medium density fibreboard (MDF) and wood studs. Premanufactured panels have been filled in with randomly oriented short-cut rapeseed and with short-cut woodchips. A modified guarded hot box method was used to designate steady and un-steady state thermo-physical parameters of such insulation panels. The examined bio-waste materials absorbed thermal fluctuations of the exterior environment and kept the indoor building environment at constant temperature regardless of such fluctuations. The ability of bio-based sandwich panels to store heat energy was found to be similar to mineral wool. Additionally, VOC (volatile organic compound) emissions of tested materials were identified using gas chromatography-mass spectrometry (GC-MS) combined with headspace solid-phase microextraction (HS-SPME) to declare materials’ harmlessness to indoor environmental quality and human wellbeing. In conclusion, bio-based short-cut materials proved to be a viable environmentally friendly and energy efficient alternative to conventionally used thermal insulations.