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1. Overcoming scale-up challenges for nanostructured photoelectrodes via one-step interface engineering

   https://doi.org/10.1016/j.ijhydene.2024.01.221  

   Rodríguez-Gutiérrez, Ingrid; Peregrino, Lizandra RP; Bedin, Karen C; Morishita, Gustavo M; Morais, Gabriel H; Castro, Ricardo HR; Leite, Edson R; Souza, Flavio L (March 2024, International Journal of Hydrogen Energy)

   Scaling up photoelectrochemical (PEC) devices for green hydrogen production is a significant challenge that requires robust and cost-effective production methods. In this study, hematite photoelectrodes has been synthesized using a cost-effective polymeric precursor solution, resulting in homogeneous ultra-thin films (~125 nm) with areas up to 200 cm2. We observed a substantial photocurrent drop as photoelectrode area increases, addressed by modifying the precursor solution with Hf4+. This modification improves the morphology and films adherence, leading to simultaneous grain|grain interface segregation and a modified FTO|hematite interface. As a result, film conductivity increases, reducing the photocurrent drop at larger photoelectrode areas. The improved charge separation and surface charge injection efficiencies allows a homogeneous photocurrent of 1.6 mA cm⁻2 at 1.45V across a 15.75 m2 electrode area, using less than 70 μg of photoactive material. Cost analysis study indicates that this low-energy fabrication method is a significant step forward in green hydrogen production, contributing to sustainable and efficient green hydrogen technologies. 

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2. Exploring awareness, implementation, and future use of urine diversion systems in U.S. university buildings

   https://doi.org/10.1007/s10669-025-10011-8  

   Grieger, Khara; Scholz, Matt; Cummings, Christopher L; Crane, Lucas; Boyer, Treavor (June 2025, Environment Systems and Decisions)

   Urine diversion systems, which include waterless urinals and urine-diverting flush toilets, offer opportunities to conserve water, recover nutrients, promote circular economies, and improve sustainability. While technical development of these systems is critical, understanding stakeholder perceptions is equally important for their successful innovation, implementation, and adoption. This study conducts an exploratory analysis of stakeholder perceptions at U.S. academic institutions regarding how urine diversion technologies fit within the broader array of water conservation technologies and factors that influence decision-making related to urine diversion in buildings. We surveyed 65 stakeholders, including executive leaders, administrators, facilities managers, building managers, and sustainability professionals—key groups responsible for the adoption and maintenance of such systems but underrepresented in prior research. Participants reported a high level of awareness of water conservation technologies and varying degrees of implementation. Across all technologies, low-flush fixtures had the highest rate of implementation and waterless urinals had the highest rate of implementation and subsequent removal due to maintenance and infrastructure challenges. Participants also indicated that compliance with plumbing codes was the most critical factor when considering the implementation of urine diversion systems, followed by efficacy and cost-savings, and water conservation and nutrient recovery were among the least important factors. Future studies should focus on aligning urine diversion systems with building codes and regulations, mitigating clogging and odors to improve acceptance and adoption, and estimating costs and benefits when deciding on their implementation. 

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3. Cui Bono: Do Open Source Software Incubator Policies and Procedures Benefit the Projects or the Incubator?

   https://doi.org/10.5334/ijc.1176  

   Sen, A.; Atkisson, C.; Schweik, C (April 2022, The international journal of the commons)

   Open source software (OSS), a form of Digital or Knowledge Commons, underlies much of the technology that we use in our daily lives. The existence and continuation of OSS relies on the contribution of private resources – personal time, volunteer energy, and effort of numerous actors (e.g., software developers’ time as a common-pool resource) – to public goods, the benefits of which are enjoyed by everyone. Nonprofit organizations such as the Apache Software Foundation (ASF) attempt to aid this process by providing various collective services to OSS projects, acting as a second-order actor in the production of the public good. To this end, the ASF Incubator has created policies – essentially rules or norms – that serve to protect its interests and, as they say, increase the sustainability of the projects. Each policy requires investment by ASF (in terms of money or the use of volunteer time) or an incubating project (in terms of taking project personnel time), the benefits of which can accrue to either party. Such policies may impose additional costs on incubating projects, leading to a decreased production of the OSS public good. Using the ASF Incubator policy documents, we construct a dataset that records who – ASF or an incubating project – bears the cost and who enjoys the benefit of each policy and procedure. We can code most policy statements as costing one party and benefiting one party. The distribution of costs and benefits according to party indicates whether the second-order actor is contributing to an increase in the public good and if they are doing so sustainably. Through a two-way ANOVA, we characterize the impact of ASF policies on the production of public goods (OSS). Being a part of ASF imposes some costs on projects, but these costs may make projects more sustainable. Our analysis shows that the distribution of costs and benefits is fairly symmetric between the ASF and incubating projects. Thus, the configuration of policies or the “institutional design” of the ASF could aid in producing the OSS public good by providing services that projects require. 

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4. The Impact of Urban Heat Island on Calibrated Building Energy Model Predictions

   Jahani, Elham; Vanage, Soham; Cetin, Kristen (January 2020, ASCE Construction Research Congress)

   Among various elements of urban infrastructure, there is significant opportunity to improve existing buildings’ sustainability, considering that approximately 40% of the total primary energy consumption and 72% of electricity consumption in United States is consumed by the building sector. Many different efforts focus on reducing the energy consumption of residential buildings. Data-validated building energy modeling methods serve the role of supporting this effort, by enabling the identification of the potential savings associated with different potential retrofit strategies. However there are many uncertainties that can impact the accuracy of energy model results, one of which is the weather input data. Measured weather data inputs located at each building can help address this concern, however, weather station data collection for each building is also costly and typically not feasible. Some weather station data is already collected, however, these are generally located at airports rather than near buildings, and thus do not capture local, spatially-varying weather conditions which are documented to occur, particularly in urban areas. In this study we address the impact of spatial temperature differences on residential building energy use. An energy model was developed in EnergyPlus for a residential building located in Mueller neighborhood of Austin, TX, and was validated using actual hourly measured electricity consumption. Using the validated model, the impact of measured spatial temperature differences on building energy consumption were investigated using multiple weather stations located throughout the urban area with different urban fractions. The results indicate that energy consumption of a residential building in a city with a 10% higher urban fraction would increase by approximately 10%. This variation in energy consumption is likely due to the impact of UHI effects occurring in urban areas with high densities. 

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5. Sensitivity of Building Energy Model Predictions to Spatial Variations in Climate under Different Levels of Urbanization

   Jahani, Elham; Vanage, Soham; Cetin, Kristen; Gallus, William; Jahn, David (January 2020, ASHRAE Annual Virtual Conference 2020)

   null (Ed.)

   In the United States, approximately 40% of the primary energy use and 72% of the electricity use belong to the building sector. This shows the significance of studying the potential for reducing the building energy consumption and buildings’ sustainability for ensuring a sustainable development. Therefore, many different efforts focus on reducing the energy consumption of residential buildings. Data-validated building energy modeling methods are among the studies for such an effort, particularly, by enabling the identification of the potential savings associated with different potential retrofit strategies. However, there are many uncertainties that can impact the accuracy of such energy model results, one of which is the weather input data. In this study, to investigate the impact of spatial temperature variation on building energy consumption, six weather stations in an urban area with various urban density were selected. A validated energy model was developed using energy audit data and high-frequency electricity consumption of a residential building in Austin, TX. The energy consumption of the modeled building was compared using the selected six weather datasets. The results show that energy use of a building in an urban area can be impacted by up to 12% due to differences in urban density. This indicates the importance of weather data in predicting energy consumption of the building. The methodology and results of this study can be used by planners and decision makers to reduce uncertainties in estimating the building energy use in urban scale. 

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