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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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At least 505 records · Page 28
All sourcesNASA NTRSDOE OSTI
DOE OSTI2025

Temperature and Strain Sensing Characteristics of a 128° YX-Cut LiNbO 3 Rayleigh-Mode SAW Sensor From Room to Cryogenic Temperatures

Accurate, passive, and wireless monitoring of cryogenic hardware is essential for high-energy physics, space propulsion, and biomedical instrumentation. Here, this study quantifies the coupled temperature-strain behavior of Rayleigh-mode surface acoustic-wave (SAW) delay-line sensors fabricated on 128° YX-cut LiNbO 3 . A nonlinear finite element (FE) model incorporating Varshni-based elastic constants, higher-order thermal expansion, and temperature-dependent piezo- and dielectric coefficients was developed and validated experimentally between 280K and 80K. Free-standing (first test condition) and bonded/wired (second test condition) devices exhibited indistinguishable thermal responses; the average temperature coefficient of delay (TCD) in the critical cryogenic range from 130K down to 80K differed by only 0.15 ppm/K (0.32%), confirming that bonding-induced stress is negligible. Over 280-80K the measured TCD was 61.77 ppm/K, while the FE model predicted an equivalent temperature coefficient of frequency (TCF) of −62.74 ppm/K with an overall coefficient of determination R2 = 0.998. In the critical cryogenic interval 130-80K the TCD fell to 47.66 ppm/K, indicating improved thermal stability at low temperature. Controlled loading (0-300 με) revealed a strain coefficient of delay (SCD) that rises from 0.53 ± 0.02 ppm/με at 300K to 1.05 ± 0.02 ppm/με at 80K. This modest sensitivity confirms that, for temperature sensing, strain is a second-order perturbation above 135K but must be compensated at deeper cryogenic levels. Overall, this work establishes a predictive multiphysics model together with repeatable wired measurements that confirm the suitability of SAW sensors for temperature and strain monitoring in extreme cryogenic environments, while also providing a baseline for future wireless implementations.

25 ENERGY STORAGE↗
DOE OSTI2015

Stochastic Optimal Scheduling of Residential Appliances with Renewable Energy Sources

This paper proposes a stochastic, multi-objective optimization model within a Model Predictive Control (MPC) framework, to determine the optimal operational schedules of residential appliances operating in the presence of renewable energy source (RES). The objective function minimizes the weighted sum of discomfort, energy cost, total and peak electricity consumption, and carbon footprint. A heuristic method is developed for combining different objective components. The proposed stochastic model utilizes Monte Carlo simulation (MCS) for representing uncertainties in electricity price, outdoor temperature, RES generation, water usage, and non-controllable loads. The proposed model is solved using a mixed integer linear programming (MILP) solver and numerical results show the validity of the model. Case studies show the benefit of using the proposed optimization model.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2014

Detailed Modeling and Response of Demand Response Enabled Appliances

Proper modeling of end use loads is very important in order to predict their behavior, and how they interact with the power system, including voltage and temperature dependencies, power system and load control functions, and the complex interactions that occur between devices in such an interconnected system. This paper develops multi-state time variant residential appliance models with demand response enabled capabilities in the GridLAB-DTM simulation environment. These models represent not only the baseline instantaneous power demand and energy consumption, but the control systems developed by GE Appliances to enable response to demand response signals and the change in behavior of the appliance in response to the signal. These DR enabled appliances are simulated to estimate their capability to reduce peak demand and energy consumption.

demand response↗
DOE OSTI2015

Model-Predictive Cascade Mitigation in Electric Power Systems With Storage and Renewables-Part I: Theory and Implementation

A novel model predictive control (MPC) scheme is developed for mitigating the effects of severe line-overload disturbances in electrical power systems. A piece-wise linear convex approximation of line losses is employed to model the effect of transmission line power flow on conductor temperatures. Control is achieved through a receding-horizon model predictive control (MPC) strategy which alleviates line temperature overloads and thereby prevents the propagation of outages. The MPC strategy adjusts line flows by rescheduling generation, energy storage and controllable load, while taking into account ramp-rate limits and network limitations. In Part II of this paper, the MPC strategy is illustrated through simulation of the IEEE RTS-96 network, augmented to incorporate energy storage and renewable generation.

Almassalkhi, MR↗
DOE OSTI2015

Networked Microgrids for Self-healing Power Systems

This paper proposes a transformative architecture for the normal operation and self-healing of networked microgrids (MGs). MGs can support and interchange electricity with each other in the proposed infrastructure. The networked MGs are connected by a physical common bus and a designed two-layer cyber communication network. The lower layer is within each MG where the energy management system (EMS) schedules the MG operation; the upper layer links a number of EMSs for global optimization and communication. In the normal operation mode, the objective is to schedule dispatchable distributed generators (DGs), energy storage systems (ESs) and controllable loads to minimize the operation costs and maximize the supply adequacy of each MG. When a generation deficiency or fault happens in a MG, the model switches to the self-healing mode and the local generation capacities of other MGs can be used to support the on-emergency portion of the system. A consensus algorithm is used to distribute portions of the desired power support to each individual MG in a decentralized way. The allocated portion corresponds to each MG’s local power exchange target which is used by its EMS to perform the optimal schedule. The resultant aggregated power output of networked MGs will be used to provide the requested power support. Test cases demonstrate the effectiveness of the proposed methodology.

Consensus Algorithm↗
DOE OSTI2019

A Model for Joint Probabilistic Forecast of Solar Photovoltaic Power and Outdoor Temperature

In this paper, a stochastic model is proposed for a joint statistical description of solar photovoltaic (PV) power and outdoor temperature. The underlying correlation emerges from solar irradiance that is responsible in part for both the variability in solar PV power and temperature. The proposed model can be used to capture the uncertainty in solar PV power and its correlation with the electric power consumption of thermostatically controlled loads. First, a model for solar PV power that explicitly incorporates the stochasticity due to clouds via a regime-switching process between the three classes of sunny , overcast and partly cloudy is proposed. Then, the relationship between temperature and solar power is postulated using a second-order Volterra model. This joint modeling is leveraged to develop a joint probabilistic forecasting method for solar PV power and temperature. Real-world datasets that include solar PV power and temperature measurements in California are analyzed and the effectiveness of the joint model in providing probabilistic forecasts is verified. The proposed forecasting methodology outperforms several reference methods thus portraying that the underlying correlation between temperature and solar PV power is well defined and only requires a simple lower-complexity sampling space.

14 SOLAR ENERGY↗
DOE OSTI2024

Optimization of District Heating Network Parameters in Steady-State Operation

Here we examine the modeling, simulation, and optimization of district heating systems, which are widely used for thermal transport using steam or hot water as a carrier. We propose a generalizable framework to specify network models and scenario parameters, and develop an optimization method for evaluating system states including pressures, fluid flowrates, and temperatures throughout the network. The network modeling includes pipes, thermal plants, pumps, and passive or controllable loads as system components. We propose basic models for thermodynamic fluid transport and enforce the balance of physical quantities in steady-state flow over co-located outgoing and return networks. We formulate an optimization problem with steam and hot water as the outgoing and return carriers, as in legacy twentieth century systems. The physical laws and engineering limitations are specified for each component type, and the thermal network flow optimization problem is formulated and solved for a realistic test network under several scenarios.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2017

FATIGUE BEHAVIOR OF SPENT NUCLEAR FUEL RODS IN SIMULATED TRANSPORTATION ENVIRONMENT

Nuclear fuel rod is composed of cladding tube and a specified number of fuel pellets contained. In the United States, spent nuclear fuel (SNF) is expected to be transported to at least one storage facility before permanent disposal. The fatigue behavior of spent nuclear fuel (SNF) rods under reversed cyclic bending must be understood in order to evaluate their vibration integrity in a transportation environment. This is especially important for high-burnup SNFs (>45 GWd/MTU). This report presents the experimental results related to Zircaloy (Zry)-4 - based surrogate rods and high-burnup SNFs, based on recent work performed at Oak Ridge National Laboratory (ORNL). The surrogate rod was made of Zry-4 cladding and alumina pellets, and high-burnup fuel rods were discharged from H.B. Robinson pressurized water reactor. The reversed cyclic bending testing was conducted at 5 Hz under loading control. The effect of pre-hydriding and burnup or irradiation on the flexural rigidity and fatigue life of cladding-pellet system were discussed. The fatigue data obtained are extremely useful to the future certification of SNF storage and transportation cask.

Wang, Jy-An John↗
DOE OSTI2022

Hydrogen and Battery Storage Technologies for Low-Cost Energy Decarbonization in Distribution Networks

Deep energy decarbonization cannot be achieved without high penetration of renewables. At higher renewable energy penetrations, the variability and intermittent nature of solar photovoltaic (PV) electricity can cause ramping issues with existing fossil fuel generation, requiring longer term energy storage to increase the reliability of grid operation. Here, a proton exchange membrane electrolyzer can produce H 2 and serves as a utility controllable load. The produced H 2 can then be stored and converted back into electricity, or mixed with natural gas, or used as transportation fuel, or chemical feedstock. This paper considers the perspective of the distribution system operator that operates the distributed energy resources on a standard IEEE 33-node distribution network considering the technical and physical constraints with the goal of minimizing total investment and operation cost. Different case studies, at very high PV penetrations are considered to show the challenges and path to net-zero emission energy production using H 2 energy. Sensitivity of utility PV costs and electrolyzer capital costs on producing H 2 at $\$1$ /kg are presented showing that the distribution network could produce 100% renewable electricity and H 2 could be produced at a cost of $\$1$ /kg by 2050 with conservative cost estimates and by 2030 with accelerated cost declines.

25 ENERGY STORAGE↗
DOE OSTI2017

Understanding the Effect of Preparative Approaches in the Formation of “Flower-like” Li 4 Ti 5 O 12 —Multiwalled Carbon Nanotube Composite Motifs with Performance as High-Rate Anode Materials for Li-Ion Battery Applications

Herein we highlight the significance of nanoscale attachment modality as an important determinant of observed electrochemical performance. Specifically, controlled loading ratios of multi-walled carbon nanotubes (MWNTs) have been successfully anchored onto the surfaces of a unique “flower-like” Li 4 Ti 5 O 12 (LTO) micro-scale sphere motif, for the first time, using a number of different and distinctive preparative approaches, including (i) a sonication method, (ii) an in situ direct-deposition approach, (iii) a covalent attachment protocol, as well as (iv) a π-π interaction strategy. In terms of structural characterization, the composites generated by physical sonication as well as non-covalent π-π interactions retained the intrinsic hierarchical “flower-like” morphology and exhibited a similar crystallinity profile as compared with that of pure LTO. By comparison, the composite prepared by an in situ direct deposition approach yielded not only a fragmented LTO structure, likely due to the possible interfering presence of the MWNTs themselves during the relevant hydrothermal reaction, but also a larger crystallite size, owing to the higher annealing temperature associated with its preparation. Finally, the composite created via covalent attachment was covered with an amorphous insulating linker, which probably led to a decreased contact area between the LTO and the MWNTs and hence, a lower crystallinity in the resulting composite. In addition electrode tests suggested that the composite generated by π-π interactions out-performed the other three analogous heterostructures, due to a smaller charge transfer resistance as well as a faster Li-ion diffusion. In particular, the LTO-MWNT composite, produced by π-π interactions, exhibited a reproducibly high rate capability as well as a reliably solid cycling stability, delivering 132 mA h g -1 at 50 C, after 100 discharge/charge cycles, including 40 cycles at a high (>20 C) rate. To conclude, such data denote the highest electrochemical performance measured to date as compared with any LTO-carbon nanotube-based composite materials previously reported, under high discharge rate conditions, and tangibly underscore the correlation between preparative methodology and the resulting performance metrics.

25 ENERGY STORAGE↗
DOE OSTI2025

evmc-supply-curves (Electric Vehicle Managed Charging Supply Curves) [SWR-25-69]

Data and a supporting lightweight Python package that describes possible costs for enabling EV managed charging from 2025 to 2050 for three dispatch mechanisms: Time-of-Use (TOU), Real Time Pricing (RTP), and direct load control (DLC) and four flexibility scenarios (Flat and Low, Mid, and High Flex).

Matsuda-Dunn, Reiko [National Renewable Energy Lab↗
DOE OSTI2013

Progress Report on Reverse Bending Fatigue Testing of Zry-4 Surrogate Rod

Testing high-burnup spent nuclear fuel (SNF) presents many challenges in areas such as specimen preparation, specimen installation, mechanical loading, load control, measurements, data acquisition, and specimen disposal because these tasks are complicated by the radioactivity of the test specimens. Unique features of the test and testing specimens demand that the test plan address these issues from the very beginning.

Fuel Transportation↗
DOE OSTI2014

TEP Power Partners Project [Tucson Electric Power]

The Arizona Governor’s Office of Energy Policy, in partnership with Tucson Electric Power (TEP), Tendril, and Next Phase Energy (NPE), formed the TEP Power Partners pilot project to demonstrate how residential customers could access their energy usage data and third party applications using data obtained from an Automatic Meter Reading (AMR) network. The project applied for and was awarded a Smart Grid Data Access grant through the U.S. Department of Energy. The project participants’ goal for Phase I is to actively engage 1,700 residential customers to demonstrate sustained participation, reduction in energy usage (kWh) and cost ($), and measure related aspects of customer satisfaction. This Demonstration report presents a summary of the findings, effectiveness, and customer satisfaction with the 15-month TEP Power Partners pilot project. The objective of the program is to provide residential customers with energy consumption data from AMR metering and empower these participants to better manage their electricity use. The pilot recruitment goals included migrating 700 existing customers from the completed Power Partners Demand Response Load Control Project (DRLC), and enrolling 1,000 new participants. Upon conclusion of the project on November 19, 2013; 1,390 Home Area Networks (HANs) were registered; 797 new participants installed a HAN; Survey respondents’ are satisfied with the program and found value with a variety of specific program components; Survey respondents report feeling greater control over their energy usage and report taking energy savings actions in their homes after participating in the program; On average, 43 % of the participants returned to the web portal monthly and 15% returned weekly; and An impact evaluation was completed by Opinion Dynamics and found average participant savings for the treatment period1 to be 2.3% of their household use during this period.2 In total, the program saved 163 MWh in the treatment period of 2013.

24 POWER TRANSMISSION AND DISTRIBUTION↗
DOE OSTI2014

NSTAR Smart Grid Pilot

NSTAR Electric & Gas Corporation (“the Company”, or “NSTAR”) developed and implemented a Smart Grid pilot program beginning in 2010 to demonstrate the viability of leveraging existing automated meter reading (“AMR”) deployments to provide much of the Smart Grid functionality of advanced metering infrastructure (“AMI”), but without the large capital investment that AMI rollouts typically entail. In particular, a central objective of the Smart Energy Pilot was to enable residential dynamic pricing (time-of-use “TOU” and critical peak rates and rebates) and two-way direct load control (“DLC”) by continually capturing AMR meter data transmissions and communicating through customer-sited broadband connections in conjunction with a standards-based home area network (“HAN”). The pilot was supported by the U.S. Department of Energy’s (“DOE”) through the Smart Grid Demonstration program. NSTAR was very pleased to not only receive the funding support from DOE, but the guidance and support of the DOE throughout the pilot. NSTAR is also pleased to report to the DOE that it was able to execute and deliver a successful pilot on time and on budget. NSTAR looks for future opportunities to work with the DOE and others in future smart grid projects.

24 POWER TRANSMISSION AND DISTRIBUTION↗
DOE OSTI2021

Staged OMB for Modular Gasifier/Burner

The goal of this final project report is to comprehensively summarize the work conducted on project DE-FE0031506. In accordance with the Statement of Project Objectives (SOPO), the University of Kentucky Center for Applied Energy Research (UK CAER) (Recipient) has developed a staged opposed multi-burner (OMB) gasifier, scaled down from a commercial gasification technology to utilize coal slurry as feed for the high-temperature gasification. The project involved the design, fabrication, commissioning, parametric testing, and performance validation of the entrained gasifier with multiple burners to narrow the major near-term technical gaps that impede the application of small-size gasification by modularizing the system. Project results verified the UK CAER approach to address the major technical challenges on the gasification modularization for a distributed application at a small scale of 1-5 MWe, while maintaining advantages in cost and flexibility, which include: 1) a cost-effective burner configuration to provide high flexibility in both load and fuel feed; 2) the modularized staged-OMB to provide better gasification performance such as a desired temperature profile, better fuel conversion, better gasification efficiency, and long lifetimes of the refractory wall and burners; and 3) load control simply through changing the number of burners firing. UK CAER’s staged gasifier configuration, fuel blend performance, and economic evaluation shows promise, as summarized in this report, as an effective means for improved gasification efficiency with reduced operation cost and process complexity.

01 COAL, LIGNITE, AND PEAT↗
DOE OSTI2022

Electric Vehicle Managed Charging: Forward-Looking Estimates of Bulk Power System Value

When and where electric vehicle charging occurs has significant implications for power systems supporting widespread electric vehicle deployment with high shares of wind and solar generation. Numerous studies have estimated the value of scheduling or otherwise managing electric vehicle charging in such power systems. This study improves on those earlier works by leveraging detailed simulation models for electric vehicle adoption, electric vehicle use, electric vehicle charging, and bulk power system operations; and linking them with methods for describing charging flexibility at both the individual vehicle and aggregate levels. This study closely analyzes electric vehicle managed charging (EVMC) performance along the dimensions of flexibility type (within-charging session or within-week scheduling), dispatch mechanism (direct load control or one of several price-based mechanisms), and participation rate, under the assumptions of ubiquitous chargers and all trips completed on time. The study is located in a passenger light-duty vehicle adoption scenario with 100% electric vehicle sales by 2035, and in an envisioned 2038 New England power system for which within-region generation is 84% clean.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
DOE OSTI2022

Remote Deployment and Setup of VOLTTRON Instances

The goal of this project is to increase the pool of people who can install and configure applications in the Intellimation platform. This will be accomplished with a joint development effort between Intellimation and PNNL to create a set of services to simplify the process for the onsite client as well as the Intellimation staff at a centralized location. Intellimation’s tagging capability, hosted in their cloud, will be leveraged to create an autoconfiguration process for selected PNNL applications such as Intelligent Load Control and AIRCX. The results of the configuration process will be sent to Intellimation field units which host the applications locally. This will allow these applications to be configured remotely and with greatly reduced effort on the part of Intellimation staff. Consequently, this will enable a greater usage of these applications and greater impact to energy efficiency than would be possible without this effort. The use of these newly developed services would allow Intellimation to reduce the cost of installation and allow them to offer the service to new and existing clients.

97 MATHEMATICS AND COMPUTING↗
DOE OSTI2024

Determining and Unlocking Untapped Demand-Side Management Potential in South Africa: Demand Response at the Grid Edge

The National Renewable Energy Laboratory (NREL), funded through the Climate Technology and Change Network (CTCN), has provided technical assistance to key energy sector entities in South Africa to examine untapped demand-side management potential. NREL partnered with the Council for Scientific and Industrial Research (CSIR) and included key South Africa stakeholders: Eskom, the South African National Energy Development Institute (SANEDI), and the Department of Mineral and Resources and Energy (DMRE), including the CTCN National Designated Entity (NDE), the Department of Science and Innovation (DSI). South Africa is currently experiencing an energy crisis with extensive load shedding. While the load shedding crisis in South Africa is a supply side problem, demand-side management provides opportunities to achieve energy efficiency and to reduce peak demand. DSM also has huge potential to help alleviate load shedding, which is a last resort form of DSM.

24 POWER TRANSMISSION AND DISTRIBUTION↗