Search NASA⌕ Search

SEARCH · Search NASA

Results for “Global Resource Assessment”

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.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 records

Improved Offshore Wind Resource Assessment in Global Climate Stabilization Scenarios

This paper introduces a technique for digesting geospatial wind-speed data into areally defined -- country-level, in this case -- wind resource supply curves. We combined gridded wind-vector data for ocean areas with bathymetry maps, country exclusive economic zones, wind turbine power curves, and other datasets and relevant parameters to build supply curves that estimate a country's offshorewind resource defined by resource quality, depth, and distance-from-shore. We include a single set of supply curves -- for a particular assumption set -- and study some implications of including it in a global energy model. We also discuss the importance of downscaling gridded wind vector data to capturing the full resource potential, especially over land areas with complex terrain. This paperincludes motivation and background for a statistical downscaling methodology to account for terrain effects with a low computational burden. Finally, we use this forum to sketch a framework for building synthetic electric networks to estimate transmission accessibility of renewable resource sites in remote areas.

17 WIND ENERGY↗

Climatic imprint on interfacially-controlled platinum-palladium resources

Abstract Iron oxide-rich laterites, soils, and regolith formed from the weathering of ultramafic rocks represent untapped unconventional resources for the critical minerals platinum and palladium, but the fundamental surficial geochemistry of these elements remains poorly understood. Depletion of Pd relative to Pt occurs in some weathering zones in semi-arid climates. The accepted model attributes this platinum-palladium chemical fractionation to preferential complexation of Pd by dissolved chloride. However, similar fractionation is not observed in laterites of humid equatorial regions despite substantial wet deposition of chloride. The established mechanistic model for Pt and Pd behavior during weathering thus inaccurately predicts the distribution of these critical minerals in many settings, hindering global resource assessment. We show through mineral-fluid partitioning experiments coupled to element-specific spectroscopy that this canonical explanation for platinum-palladium fractionation is invalid: chloride complexation does not differentially mobilize Pd versus Pt. Instead, mineral-specific interfacial reactions control Pd and Pt accumulation. Modeling of platinum-palladium fractionation in representative weathering zone profiles demonstrates sub-equal retention in goethite-rich settings and Pd depletion in hematite-rich zones, accurately predicting trends observed in soils and laterites. Iron oxide mineralogy, reflecting modern and past regional climate conditions, is likely the primary determinant of Pt and Pd endowment in weathering zone resources. This new model for Pt and Pd mobilization and accumulation behavior provides a mechanistic foundation for exploration and recovery of platinum group elements from novel ultramafic regolith deposits.

58 GEOSCIENCES↗

An improved global wind resource estimate for integrated assessment models

This study summarizes initial steps to improving the robustness and accuracy of global renewable resource and techno-economic assessments for use in integrated assessment models. We outline a method to construct country-level wind resource supply curves, delineated by resource quality and other parameters. Using mesoscale reanalysis data, we generate estimates for wind quality, both terrestrial and offshore, across the globe. Because not all land or water area is suitable for development, appropriate database layers provide exclusions to reduce the total resource to its technical potential. We expand upon estimates from related studies by: using a globally consistent data source of uniquely detailed wind speed characterizations; assuming a non-constant coefficient of performance for adjusting power curves for altitude; categorizing the distance from resource sites to the electric power grid; and characterizing offshore exclusions on the basis of sea ice concentrations. The product, then, is technical potential by country, classified by resource quality as determined by net capacity factor. Additional classifications dimensions are available, including distance to transmission networks for terrestrial wind and distance to shore and water depth for offshore. We estimate the total global wind generation potential of 560 PWh for terrestrial wind with 90% of resource classified as low-to-mid quality, and 315 PWh for offshore wind with 67% classified as mid-to-high quality. These estimates are based on 3.5 MW composite wind turbines with 90 m hub heights, 0.95 availability, 90% array efficiency, and 5 MW/km 2 deployment density in non-excluded areas. We compare the underlying technical assumption and results with other global assessments.

17 WIND ENERGY↗

An Improved Global Wind Resource Estimate for Integrated Assessment Models: Preprint

This paper summarizes initial steps to improving the robustness and accuracy of global renewable resource and techno-economic assessments for use in integrated assessment models. We outline a method to construct country-level wind resource supply curves, delineated by resource quality and other parameters. Using mesoscale reanalysis data, we generate estimates for wind quality, both terrestrial and offshore, across the globe. Because not all land or water area is suitable for development, appropriate database layers provide exclusions to reduce the total resource to its technical potential. We expand upon estimates from related studies by: using a globally consistent data source of uniquely detailed wind speed characterizations; assuming a non-constant coefficient of performance for adjusting power curves for altitude; categorizing the distance from resource sites to the electric power grid; and characterizing offshore exclusions on the basis of sea ice concentrations. The product, then, is technical potential by country, classified by resource quality as determined by net capacity factor. Additional classifications dimensions are available, including distance to transmission networks for terrestrial wind and distance to shore and water depth for offshore. We estimate the total global wind generation potential of 560 PWh for terrestrial wind with 90% of resource classified as low-to-mid quality, and 315 PWh for offshore wind with 67% classified as mid-to-high quality. These estimates are based on 3.5 MW composite wind turbines with 90 m hub heights, 0.95 availability, 90% array efficiency, and 5 MW/km2 deployment density in non-excluded areas. We compare the underlying technical assumption and results with other global assessments.

17 WIND ENERGY↗

What are the effects of Agro-Ecological Zones and land use region boundaries on land resource projection using the Global Change Assessment Model?

Understanding the potential impacts of climate change is complicated by mismatched spatial representations between gridded Earth System Models (ESMs) and Integrated Assessment Models (IAMs), whose regions are typically larger and defined by geopolitical and biophysical criteria. In this study we address uncertainty stemming from the construction of land use regions in an IAM, the Global Change Assessment Model (GCAM), whose regions are currently based on historical climatic conditions (1961-1990). We re-define GCAM’s regions according to projected climatic conditions (2070-2099), and investigate how this changes model outcomes for land use, agriculture, and forestry. By 2100, we find potentially large differences in projected global and regional area of biomass energy crops, fodder crops, harvested forest, and intensive pasture. These land area differences correspond with changes in agricultural commodity prices and production. These results have broader implications for understanding policy scenarios and potential impacts, and for evaluating and comparing IAM and ESM simulations.

54 ENVIRONMENTAL SCIENCES↗

Mapping and Synthesis of International Biomass Supply Assessments

This report, Mapping and Synthesis of International Biomass Supply Assessments (or Global Biomass Resource Assessment) is the first step in a long-term process to assemble data from around the globe into a virtual repository that can be updated and provide user-friendly access to the data. The Clean Energy Ministerial (CEM) Biofuture Platform Initiative recommended that research be completed to “address the need for internationally accepted benchmarks quantifying sustainable biomass feedstock supplies.” To act upon the CEM Biofuture recommendation, in 2024, the U.S. Department of Energy (DOE) commissioned Oak Ridge National Laboratory (ORNL) to prepare this report as the primary deliverable for a one-year assignment to assemble data into a citable form that could help resolve the persistent question presented related to bioenergy policy, “Is there enough sustainable biomass?” In response to that query, this report includes information received by August 2024 from national CEM representatives, collaborators, and public sources on current and future sustainable biomass supplies in 62 nations,and subsequently documents (a) the approach used by ORNL to analyze and categorize the information received in a manner that enables aggregation and comparability; and (b) recommendations for next steps and guidelines to help others update and harmonize future assessments of global sustainable biomass supplies.

09 BIOMASS FUELS↗

Addressing Investment Barriers by Improving Documentation of Sustainable Biomass Resources (Workshop Report)

On May 8, 2025, Oak Ridge National Laboratory (ORNL), in collaboration with IEA Bioenergy Task 43 and the Biofuture Platform, convened an international workshop in Vancouver, Canada to improve the Global Biomass Resource Assessment. This effort addresses investment barriers in the global bioeconomy by improving the transparency, consistency, and usability of biomass supply data. The workshop gathered 38 participants from 11 countries, representing government agencies, academia, and industry. Participants reviewed the status of the biomass dataset, tested the data-sharing platform, and provided direct input on priorities for improvement.

09 BIOMASS FUELS↗

Ocean Thermal Extractable Energy Visualization (Final Technical Report)

The Ocean Thermal Extractable Energy Visualization (OTEEV) project focuses on assessing the Maximum Practicably Extractable Energy (MPEE) from the world's ocean thermal resources. MPEE is defined as being sustainable and technically feasible, given today's state-of-the-art ocean energy technology. Under this project the OTEEV team developed a comprehensive Geospatial Information System (GIS) dataset and software tool, and used the tool to provide a meaningful assessment of MPEE from the global and domestic U.S. ocean thermal resources. The OTEEV project leverages existing NREL renewable energy GIS technologies and integrates extractable energy estimated from quality-controlled data and projected optimal achievable energy conversion rates. Input data are synthesized from a broad range of existing in-situ measurements and ground-truthed numerical models with temporal and spatial resolutions sufficient to reflect the local resource. Energy production rates are calculated for regions based on conversion rates estimated for current technology, local energy density of the resource, and sustainable resource extraction. Plant spacing and maximum production rates are then estimated based on a default plant size and transmission mechanisms. The resulting data are organized, displayed, and accessed using a multi-layered GIS mapping tool, http://maps.nrel.gov/mhk_atlas with a user-friendly graphical user interface.

14 SOLAR ENERGY↗

An assessment of global Ocean Thermal Energy Conversion resources under broad geographical constraints

Rates of Ocean Thermal Energy Conversion (OTEC) are assessed with a high-resolution ocean general circulation model when broad geographical restrictions are imposed on the OTEC implementation area. This may correspond to practical or legal limitations, such as the cost of long submarine power cables or the extent of Exclusive Economic Zones. Because some environmental effects predicted under large-scale OTEC scenarios exhibit a strong asymmetry among major oceanic basins, numerical experiments where the OTEC domain is restricted to such specific areas are also conducted. Results suggest that in all cases, a rate of about 0.2 TW per Sverdrup of OTEC deep cold seawater is sustained when overall OTEC net power peaks. At that juncture, temperature profiles in the OTEC implementation areas are affected in similar ways, while the strength of the Thermohaline Circulation roughly doubles. Overall geographical constraints simply defined by distance to shore, given the model’s 1° horizontal resolution, produce global OTEC net power maxima of 12–14 TW. In such cases, OTEC net power density approximately increases in inverse proportion to the OTEC implementation area. Limiting OTEC development to the Indo-Pacific yields results similar to the global case with a maximum proportional to the implementation area (12 TW), but simulations restricted to the Atlantic behave quite differently. In the latter case, OTEC net power peaks a little over 5 TW. In conclusion, it is estimated that producing half the predicted power maxima would substantially limit large-scale environmental temperature changes in each case.

13 HYDRO ENERGY↗

An Assessment of Global Ocean Thermal Energy Conversion Resources With a High-Resolution Ocean General Circulation Model

Global rates of ocean thermal energy conversion (OTEC) are assessed with a high-resolution (1 deg × 1 deg) ocean general circulation model (OGCM). In numerically intensive simulations, the OTEC process is represented by a pair of sinks and a source of specified strengths placed at selected water depths across the oceanic region favorable for OTEC. Results broadly confirm earlier estimates obtained with a coarse (4 deg × 4 deg) OGCM, but with the greater resolution and more elaborate description of key physical oceanic mechanisms in the present case, the massive deployment of OTEC systems appears to affect the global environment to a relatively greater extent. The maximum global OTEC power production drops to 14 TW, or about half of previously estimated levels, but it would be achieved with only one-third as many OTEC systems. Environmental effects at maximum OTEC power production are generally similar in both sets of simulations. The oceanic surface layer would cool down in tropical OTEC regions with a compensating warming trend elsewhere. Some heat would penetrate the ocean interior until the environment reaches a new steady state. A significant boost of the oceanic thermohaline circulation (THC) would occur. Although all simulations with given OTEC flow singularities were run for 1000 years to ensure stabilization of the system, convergence to a new equilibrium was generally achieved much faster, i.e., roughly within a century. Here, with more limited OTEC scenarios, a global OTEC power production of the order of 7 TW could still be achieved without much effect on ocean temperatures.

13 HYDRO ENERGY↗

Physics and Environmental Assessments for a Heavy-Water Moderated, Molten Uranium Reactor Concept

Previous papers describe a method for controlling a thermal nuclear reactor by moderator displacement between the reactor core and the reflector. The low neutron loss and high control range of this method enable a design for a molten natural uranium fueled and cooled heavy water moderated reactor. The design is geometrically similar to CANDU (Canadian Deuterium Uranium) reactors but with fewer, larger, vertically oriented fuel tubes. The fuel tubes contain molten natural uranium as both the fuel and the coolant instead of fuel rods and water coolant. The large fuel tubes have a mixed spectrum which is largely thermal at the periphery of the tubes with a very hard spectrum in the large central region of the tube. This configuration provides a fast fission rate of around 15% (mostly of U-238) and an initial conversion ratio of around 1.15. It is a hypothetical reactor because it is unclear what materials could actually be used to fabricate the fuel tubes and other primary coolant plumbing. The molten uranium serves both as the fuel and the primary coolant and as such is continuously circulated through the fuel tubes in the reactor core, the primary heat exchange, and back to the the reactor core. This means that at any point in time all the fuel has the same isotopic configuration no matter where it is in the reactor or heat exchanger. Over time the isotopic configuration changes, but it changes uniformly for all the fuel. Uranium melts at 1135 deg. C, so a proposed temperature range for the circulating molten uranium is 1200 deg. C at the exit of the heat exchanger and entry to the core fuel tubes and 1400 deg. C at the exit from the core fuel tubes and the entry into the heat exchanger. The advantages of this design include: 1. Reduced nuclear proliferation concern because of natural uranium fuel. 2. High conversion ratio and large fuel mass provides 30 to 100 year fuel life. 3. No heavy metal waste because fissile content increases over the fuel life. 4. High output temperatures are suitable for high efficiency turbine generators. This assessment will examine three perspectives: reactor physics, regional grid management, and global resource utilization and impact. This assessment will examine three perspectives: reactor physics, regional grid management, and global resource utilization and impact. The proposed reactor type can generate much of the future CO{sub 2} emission free electric power demand with a low impact on total uranium required to be mined, zero heavy metal waste produced, zero enrichment capability required, and capacity (with thermal storage) to meet fluctuating demand. There are engineering issues to be addressed before such a reactor can be built, but thanks to the demand for high efficiency gas turbines and other high temperature applications, high temperature materials and technology are developing rapidly. An operating temperature of 1400 degrees C does not seem unreasonable in the near future. The implied advantages of this reactor type compared to other existing or proposed reactors suggest that further work on the issues raised would be well worthwhile. (authors)

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗

Ocean Thermal Energy Conversion Life Cycle Cost Assessment, Final Technical Report, 30 May 2012

The Ocean Thermal Energy Conversion (OTEC) Life Cycle Cost Assessment (OLCCA) is a study performed by members of the Lockheed Martin (LM) OTEC Team under funding from the Department of Energy (DOE), Award No. DE-EE0002663, dated 01/01/2010. OLCCA objectives are to estimate procurement, operations and maintenance, and overhaul costs for two types of OTEC plants: -Plants moored to the sea floor where the electricity produced by the OTEC plant is directly connected to the grid ashore via a marine power cable (Grid Connected OTEC plants) -Open-ocean grazing OTEC plant-ships producing an energy carrier that is transported to designated ports (Energy Carrier OTEC plants) Costs are developed using the concept of levelized cost of energy established by DOE for use in comparing electricity costs from various generating systems. One area of system costs that had not been developed in detail prior to this analysis was the operations and sustainment (O&S) cost for both types of OTEC plants. Procurement costs, generally referred to as capital expense and O&S costs (operations and maintenance (O&M) costs plus overhaul and replacement costs), are assessed over the 30 year operational life of the plants and an annual annuity calculated to achieve a levelized cost (constant across entire plant life). Dividing this levelized cost by the average annual energy production results in a levelized cost of electricity, or LCOE, for the OTEC plants. Technical and production efficiency enhancements that could result in a lower value of the OTEC LCOE were also explored. The thermal OTEC resource for Oahu, Hawaii and projected build out plan were developed. The estimate of the OTEC resource and LCOE values for the planned OTEC systems enable this information to be displayed as energy supplied versus levelized cost of the supplied energy; this curve is referred to as an Energy Supply Curve. The Oahu Energy Supply Curve represents initial OTEC deployment starting in 2018 and demonstrates the predicted economies of scale as technology and efficiency improvements are realized and larger more economical plants deployed. Utilizing global high resolution OTEC resource assessment from the Ocean Thermal Extractable Energy Visualization (OTEEV) project (an independent DOE project), Global Energy Supply Curves were generated for Grid Connected and Energy Carrier OTEC plants deployed in 2045 when the predicted technology and efficiencies improvements are fully realized. The Global Energy Supply Curves present the LCOE versus capacity in ascending order with the richest, lowest cost resource locations being harvested first. These curves demonstrate the vast ocean thermal resource and potential OTEC capacity that can be harvested with little change in LCOE.

99 GENERAL AND MISCELLANEOUS↗

Influence of Groundwater Extraction Costs and Resource Depletion Limits on Simulated Global Nonrenewable Water Withdrawals Over the Twenty‐First Century

Abstract Future rates of global groundwater depletion will depend on the economic and environmental viability of extracting water from increasingly stressed aquifers. Here we analyze global groundwater depletion by considering these factors explicitly. Global gridded groundwater availability and extraction cost data are aggregated to produce nonrenewable resource supply curves for 235 major river basins and geopolitical regions. These resources are then exposed to dynamically generated demands for water in a fully coupled, multisectoral, global simulation. As groundwater head levels drop, imposing greater capital and operating costs to bring water to the surface, modeled water use sectors are able to deploy a range of supply‐ and demand‐driven adaptive responses. Results demonstrate large sensitivity in global groundwater depletion rates to adjustments in resource exploitability. Extraction costs moderate demands for nonrenewable water substantially, resulting in the onset of a decline in global groundwater depletion rates within the twenty‐first century. New groundwater depletion hot spots may emerge as crop producers abandon overexploited basins and expand croplands in regions with cheaper, more plentiful water resources.

54 ENVIRONMENTAL SCIENCES↗

Evidence-based indicator approach to guide preliminary environmental impact assessments of hydropower development

Global expansion of hydropower resources has increased in recent years to meet growing energy demands and fill worldwide gaps in electricity supply. However, hydropower induces significant environmental impacts on river ecosystems - impacts that are addressed through environmental impact assessment (EIA) processes. The need for effective EIA processes is increasing as environmental regulations are either stressed in developing countries undertaking rapid expansion of hydropower capacity or time- and resource-intensive in developed countries. Part of the challenge in implementing EIAs lies in reaching a consensus among stakeholders regarding the most important environmental factors as the focus of impact studies. To help address this gap, we developed a weight-of-evidence approach (and toolkit) as a preliminary and coarse assessment of the most relevant impacts of hydropower on primary components of the river ecosystem, as identified using river function indicators. Through a science-based questionnaire and predictive model, users identify which environmental indicators may be impacted during hydropower development as well as those indicators that have the highest levels of uncertainty and require further investigation. Furthermore, an assessment tool visualizes inter-dependent indicator relationships, which help formulate hypotheses about causal relationships explored through environmental studies. We apply these tools to four existing hydropower projects and one hypothetical new hydropower project of varying sizes and environmental contexts. We observed consistencies between the output of our tools and the Federal Energy Regulatory Commission licensing process (inclusive of EIAs) but also important differences arising from holistic scientific evaluations (our toolkit) versus regulatory policies. The tools presented herein are aimed at increasing the efficiency of the EIA processes that engender environmental studies without loss of rigor or transparency of rationale necessary for understanding, considering, and mitigating the environmental consequences of hydropower.

54 ENVIRONMENTAL SCIENCES↗

Global interfertility and heterosis in sugar kelp populations: a next step in sugar kelp breeding

Abstract The potential of seaweed aquaculture is restricted by high labor, production and processing costs, leading to low economic viability. Selective breeding can improve yields and cultivation efficiency, thereby decreasing production costs. Until now, genetic resources as input for Saccharina latissimabreeding trials have been sourced strictly locally, due to concerns regarding outplanting genetically exogenous material in local waters. Here we study, for the first time, worldwide interregional fertility of the seaweedS. latissima,in order to assess the potential of including globalS. latissimagenetic resources for selective breeding with regard to heterosis. We quantified the yield (as an indicative aquacultural performance) and morphological traits of intra- and interregionalS. latissimahybrids originating from a broad range of locations in a common garden experiment. Our results show that the practical application of worldwideS. latissimagenetic resources in breeding programs is feasible based on global interfertility. We found a wide morphological diversity of hybrids and observed significant heterosis in interregional hybrids. The degree of heterosis could not be linked to geographic distance. These findings reveal that worldwide genetic resources can considerably contribute toS. latissimabreeding programs and could offer a major next step in improving yields and quality traits.

Biotechnology & Applied Microbiology↗

Adversarial super-resolution of climatological wind and solar data

Accurate and high-resolution data reflecting different climate scenarios are vital for policy makers when deciding on the development of future energy resources, electrical infrastructure, transportation networks, agriculture, and many other societally important systems. However, state-of-the-art long-term global climate simulations are unable to resolve the spatiotemporal characteristics necessary for resource assessment or operational planning. We introduce an adversarial deep learning approach to super resolve wind velocity and solar irradiance outputs from global climate models to scales sufficient for renewable energy resource assessment. Using adversarial training to improve the physical and perceptual performance of our networks, we demonstrate up to a 50 × resolution enhancement of wind and solar data. In validation studies, the inferred fields are robust to input noise, possess the correct small-scale properties of atmospheric turbulent flow and solar irradiance, and retain consistency at large scales with coarse data. An additional advantage of our fully convolutional architecture is that it allows for training on small domains and evaluation on arbitrarily-sized inputs, including global scale. We conclude with a super-resolution study of renewable energy resources based on climate scenario data from the Intergovernmental Panel on Climate Change’s Fifth Assessment Report.

14 SOLAR ENERGY↗

Climate Mitigation Policy Implications for Global Irrigation Water Demand

Energy, water and land are scarce resources, critical to humans. Developments in each affect the availability and cost of the others, and consequently human prosperity. Measures to limit greenhouse gas concentrations will inevitably exact dramatic changes on energy and land systems and in turn alter the character, magnitude and geographic distribution of human claims on water resources. We employ the Global Change Assessment Model (GCAM), an integrated assessment model to explore the interactions of energy, land and water systems in the context of alternative policies to limit climate change to three alternative levels: 2.5 Wm-2 (445 ppm CO2-e), 3.5 Wm-2 (535 ppm CO2-e) and 4.5 Wm-2 (645 ppm CO2-e). We explore the effects of alternative land-use emissions mitigation policy options—one which values terrestrial carbon emissions equally with fossil fuel and industrial emissions, and an alternative which places no penalty on land-use change emissions. We find that increasing populations and economic growth could be anticipated to lead to increased demand for water for agricultural systems (+200%), even in the absence of climate change. In general policies to mitigate climate change will increase agricultural demands for water, regardless of whether or not terrestrial carbon is valued or not. Burgeoning demands for water are driven by the demand for bioenergy in response to emissions mitigation policies. We also find that the policy matters. Increases in the demand for water when terrestrial carbon emissions go un-prices are vastly larger than when terrestrial system carbon emissions are prices at the same rate as fossil fuel and industrial emissions. Our estimates for increased water demands when terrestrial carbon systems go un-priced are larger than earlier studies. We find that the deployment of improved irrigation delivery systems could mitigate some of the increase in water demands, but cannot reverse the increases in water demands when terrestrial carbon emissions go un-priced. Finally we estimates that the geospatial pattern of water demands could stress some parts of the world, e.g. China, India and other countries in south and east Asia, earlier and more intensely than in other parts of the world, e.g. North America.

agriculture water↗