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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Describes stratigraphic and lithologic work on the Cypress Sandstone, including the lateral and vertical variability of reservoirs across the Clay City Anticline.
With the emergence of cutting-edge transportation technologies, such as electric vehicles (EVs), connected and autonomous vehicles, and drones, the adoption of multimodal freight mobility has the potential to improve efficiency and save more energy. This paper proposes a hybrid tour-based model to evaluate the energy impact of multimodal intra-city freight movement for future scenarios. The model is built based on the traveling salesman problem model and clustering techniques. A case study using autonomous electric vehicles for package delivery is evaluated. The study was conducted using data analyzed from the Columbus, Ohio, metropolitan area. The initial results show that multimodal package delivery using autonomous EVs reduced total travel time by 45% and saved total energy use by 19%, but increased total vehicle miles traveled by 15% when compared with the baseline scenario.
Join this spotlight session to learn more about the SolSmart program and how it can help your city or county cut red-tape around solar.
This case study describes how Rocky Mountain Power, Questar, and Salt Lake City worked together to develop a way for commercial building owners to get access to whole-building energy data more efficiently. It details the use of a stakeholder engagement forum to enable business owners to comply with local energy benchmarking ordinances.
The purpose of this study is to develop a methodology for modeling intra-city freight delivery tours using innovative modes and alternative last mile delivery scenarios to determine potential energy savings in Columbus, Ohio. This study is part of the Department of Energy (DOE)’s SMART (Systems and Modeling for Accelerated Research in Transportation) Mobility Multi-Modal Freight Pillar. It is a partnership with the Oak Ridge National Laboratory, Idaho National Laboratory, National Renewable Energy Laboratory, United Parcel Service – Columbus, Ohio, and the Mid-Ohio Regional Planning Commission.
The Tuba City, Arizona, Disposal Site is located in the Navajo Nation and near the Hopi Reservation. A uranium mill operated at the site from 1956 to 1966. During the operational period, mill tailings were slurried to an unlined impoundment. Excess slurry water was transferred to unlined evaporation ponds. Groundwater contamination resulting from the infiltration of fluids in the mill tailings impoundment and evaporation ponds was characterized in the 1990's. The site's Groundwater Compliance Action Plan was prepared in 1999, and a groundwater extraction and treatment system was constructed in 2002. Issues with aquifer productivity and treatment plant reliability led to the suspension of operations in 2014. The limitations of the remediation system prompted a realization that the site conceptual model should be reevaluated. An integrated study to better understand the geochemical and hydrologic factors affecting contaminant transport, to support the development of a new groundwater compliance strategy, was initiated in 2017 and is ongoing. In addition to the groundwater science components, the study included the evaluation of enhanced evaporation methods. The integrated evaluation will lead to refinement of the site groundwater flow model and development of a contaminant transport model and subsequent development of remedial alternatives. Remedial alternatives will be evaluated to determine a new groundwater compliance strategy. The objectives of geochemical testing were to confirm and quantify geochemical reactions controlling uranium fate and transport. These reactions are important because they control the distribution of uranium on the solid phase; potential for release from the solid phase; mobility of uranium in the water phase; and potential for uranium redistribution onto the currently uncontaminated solid phase. A key outcome is the change in understanding of the mass of uranium in the subsurface that is potentially soluble. These results contradict the previous basis for remediation: that uranium was almost exclusively present in soluble form, within the boundaries of the contaminant plume. Testing showed that uranium sorption downgradient from the plume was measurable but relatively minimal. The movement of other mill-related constituents (nitrate, sulfate, alkalinity) results in the dissolution of naturally occurring uranium and a higher than background concentration of uranium in groundwater. These constituents are not subject to sorption, and their downgradient concentrations are reduced only by diffusion and dispersion. The geochemical testing provides conceptual and quantitative information on potential plume migration. While the testing revealed the potential availability of uranium contaminant sources, the aquifer buffering capacity, pH, and presence of oxygen in groundwater may, individually or in combination, be controlling factors for plume movement. Evaluation of evaporative treatment alternatives was undertaken to determine one or more sustainable and efficient methods capable of treating 151 liters per minute (L/min) (40 gallons per minute), the annual average flow rate. In addition to establishing the baseline capacity for evaporation using the site's existing pond, prospective methods of enhanced evaporation included preheating water before inflow to the evaporation pond, vertical circulation in the pond, dye addition, and Wind-Aided Intensified Evaporation. Consideration of a 151 L/min evaporative treatment arose from previous analysis of extraction well production rates and contaminant mass removal, which indicated that about 80% contaminant removal, relative to full-scale operation of the site's groundwater treatment plant, could be achieved with a smaller capacity system. The lower-flow evaporative option also represented a potentially more sustainable treatment system in comparison to restarting or reconfiguring the groundwater treatment plant. Aquifer pumping tests were designed to develop or improve estimates of hydraulic properties such as transmissivity, horizontal and vertical hydraulic conductivity, storativity, and storage coefficient. Testing involved pumping from one well at a constant flow rate for up to 5 days while monitoring groundwater drawdown in the pumping well and five surrounding wells and then shutting down the pumping well to observe groundwater recovery. The aquifer pumping test results provide insight regarding the hydraulics of the saturated zone. The saturated zone is in a low-conductivity formation with preferential flow in the horizontal direction. The aquifer exhibits low vertical conductance. The use of AQTESOLV software indicates that the saturated zone is a layered system due to the cross-bedded sand-grain orientation within the Navajo Sandstone. These indicators of limited vertical flow provide a potential justification for the observed depth of the contaminant plume of 15-46 meters (50-150 feet) below ground surface). Given the relatively low vertical conductance, groundwater extraction should be focused on the upper portions of the saturated zone. Aquifer response testing provided an improved understanding of aquifer characteristics. However, the primary objective, to identify optimal groundwater extraction strategies, has not been fully addressed. A list of path forward activities for hydrologic analyses was developed, with an overarching objective of providing input parameters for groundwater flow and contaminant transport modeling. Defensible predictions of contaminant transport, through modeling, are critical to the development of a new site groundwater compliance strategy. (authors)
Many households in the City of Columbia, South Carolina, could save hundreds of dollars annually on their energy bills, reduce carbon emissions, and improve comfort with energy efficiency retrofits and upgrades in their homes and apartments. As part of the U.S. Department of Energy's (DOE) Communities LEAP (Local Energy Action Program) pilot, the National Renewable Energy Laboratory (NREL) analyzed energy efficiency and electrification upgrades for about 94,000 housing units in Columbia.
This checklist provides a detail project flow for building owners pursuing onsite community solar in New York City. This includes: (1) Evaluate your building; (2) Find a solar developer; (3) Project approvals; (4) Project construction & commissioning; and (5) Ongoing O&M and payments.
Geothermal heat pumps can be great alternatives to air conditioners and furnaces, and require less electricity to run. This case study focuses on Greensburg, Kansas, City Hall and is part of a series: https://www.energy.gov/eere/geothermal/geothermal-heat-pump-case-studies.
In recent years, bikesharing systems have become increasingly popular as affordable and sustainable micromobility solutions. Advanced mathematical models such as machine learning are required to generate good forecasts for bikeshare demand. Here, this study proposes a machine learning modeling framework to estimate hourly demand in a large-scale bikesharing system. Two Extreme Gradient Boosting models were developed: one using data from before the COVID-19 pandemic (March 2019 to February 2020) and the other using data from during the pandemic (March 2020 to February 2021). Furthermore, a model interpretation framework based on SHapley Additive exPlanations was implemented. Based on the relative importance of the explanatory variables considered in this study, share of female users and hour of day were the two most important explanatory variables in both models. However, the month variable had higher importance in the pandemic model than in the pre-pandemic model.
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Effective urban ventilation through decent urban planning and building design can alleviate the deterioration of the urban built environment. Furthermore, natural ventilation requirements and guidelines in current building codes and standards are either qualitative or quantitative but subject to an absolute indoor airspeed threshold without considering the outdoor wind environment. To fill this gap, this paper develops an urban-scale coupled indoor and outdoor computational fluid dynamics (CFD) model and defines a novel ventilation index to assess natural ventilation potential. The index considers wind environments of both indoor and outdoor spaces.
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Buildings account for 35% of the global final energy demand. Efficiency improvements and advanced control strategies have a significant impact in the reduction of energy costs and CO2 emissions. Building energy simulation is widely used to help planners, contractors, and building owners analyse diverse options regarding the planning and management of energy consumption in buildings. Furthermore, recent advances in data processing and computing have led to the development of sophisticated machine learning algorithms that can learn from large datasets, e.g., sensor data from buildings, and use them to develop building-specific adaptive and automatic energy controllers. Control algorithms, such as deep reinforcement learning can tune themselves, are model-free, and economical to implement. In this paper, we introduce an integrated simulation environment that combines CitySim, a fast building energy simulator, and TensorFlow, a platform for efficient implementation of advanced machine learning algorithms. The integration is achieved via Keras - an API for TensorFlow - and a set of text and csv files for data transfer between the applications. This new environment will allow researchers to investigate novel learning control algorithms, and demonstrate their robustness and potential for diverse applications in the built environment. We present two case studies for energy savings and demand response, respectively.
The CI (Ivuna-type) carbonaceous material returned from asteroids Ryugu and Bennu contain mobilized sodium from the evaporation or freezing of liquid water into brines, shedding light on the internal structure of ice-rich CI-type worlds and the formation of prebiotic organic compounds. The formation of brines has not been demonstrated in CM (Mighei-type) carbonaceous chondrites, which also supplied organic matter to the early Earth. Here, we announce the fall of a primitive meteorite from a daytime fireball over the New York metropolitan area in July 2024. It is a CM2 breccia that contains unique CM1 clasts rich in water and sodium. The meteorite contains abundant amino acids and other products of organic chemistry in brines that reveal subsurface processes on CM-type asteroid parent bodies.
This annual guide features a comprehensive list of 2014 light-duty alternative fuel and advanced vehicles, grouped by fuel and technology. The guide provides model-specific information on vehicle specifications, manufacturer suggested retail price, fuel economy, energy impact, and emissions. The information can be used to identify options, compare vehicles, and help inform purchase decisions.
This report summarizes various policies for encouraging investment and installation of renewable energy across the country. In particular, we attempt to explain the benefits of, and considerations behind, each policy type and provide examples of implementation across the United States While recognized as important, this report does not address policies or examples of successful energy efficiency or alternative-fuel vehicle strategies. In addition, we summarize the renewable energy policy strategies undertaken by three areas of the United States: New Jersey, Hawaii, and San Francisco.
This module will help attendees understand nuances between different types of renewable energy goals, the importance of terminology when setting and announcing goals, the value of formally clarifying priorities, and how priorities may impact procurement options. It is the first training in a series intended to help municipal staff procure solar PV for their land and buildings.