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DOE OSTI2014

Competing effects of electronic and nuclear energy loss on microstructural evolution in ionic-covalent materials

Ever increasing energy needs have raised the demands for advanced fuels and cladding materials that withstand the extreme radiation environments with improved accident tolerance over a long period of time. Ceria (CeO2) is a well known ionic conductor that is isostructural with urania and plutonia-based nuclear fuels. In the context of nuclear fuels, immobilization and transmutation of actinides, CeO2 is a model system for radiation effect studies. Covalent silicon carbide (SiC) is a candidate for use as structural material in fusion, cladding material for fission reactors, and an inert matrix for the transmutation of plutonium and other radioactive actinides. Understanding microstructural change of these ionic-covalent materials to irradiation is important for advanced nuclear energy systems. While displacements from nuclear energy loss may be the primary contribution to damage accumulation in a crystalline matrix and a driving force for the grain boundary evolution in nanostructured materials, local non-equilibrium disorder and excitation through electronic energy loss may, however, produce additional damage or anneal pre-existing defects. At intermediate transit energies where electronic and nuclear energy losses are both significant, synergistic, additive or competitive processes may evolve that affect the dynamic response of materials to irradiation. The response of crystalline and nanostructured CeO2 and SiC to ion irradiation are studied under different nuclear and electronic stopping powers to describe some general material response in this transit energy regime. Although fast radiation-induced grain growth in CeO2 is evident with no phase transformation, different fluence and dose dependence on the growth rate is observed under Si and Au irradiations. While grain shrinkage and amorphization are observed in the nano-engineered 3C SiC with a high-density of stacking faults embedded in nanosize columnar grains, significantly enhanced radiation resistance is attributed to stacking faults that promote efficient point defect annihilation. Moreover, competing effects of electronic and nuclear energy loss on the damage accumulation and annihilation are observed in crystalline 4H-SiC. Systematic experiments and simulation effort are needed to understand the competitive or synergistic effects.

36 MATERIALS SCIENCE↗

DOE OSTI2018

Energy Savings Analysis of the Proposed NYStretch-Energy Code 2018

This study was conducted by the Pacific Northwest National Laboratory (PNNL) in support of the stretch energy code development led by the New York State Energy Research and Development Authority (NYSERDA). In 2017 NYSERDA developed its 2016 Stretch Code Supplement to the 2016 New York State Energy Conservation Construction Code (hereinafter referred to as “NYStretch-Energy”). NYStretch-Energy is intended as a model energy code for statewide voluntary adoption that anticipates other code advancements culminating in the goal of a statewide Net Zero Energy Code by 2028. Since then, NYSERDA continues to develop the NYStretch-Energy Code 2018 edition. To support the effort, PNNL conducted energy simulation analysis to quantify the energy savings of proposed commercial provisions of the NYStretch-Energy Code (2018) in New York. The focus of this project is the 20% improvement over existing commercial model energy codes. A key requirement of the proposed stretch code is that it be ‘adoptable’ as an energy code, meaning that it must align with current code scope and limitations, and primarily impact building components that are currently regulated by local building departments. It is largely limited to prescriptive measures, which are what most building departments and design projects are most familiar with. This report describes a set of energy-efficiency measures (EEMs) that demonstrate 20% energy savings over ANSI/ASHRAE/IES Standard 90.1-2013 (ASHRAE 2013) across a broad range of commercial building types and all three climate zones in New York. In collaboration with New Building Institute, the EEMs were developed from national model codes and standards, high-performance building codes and standards, regional energy codes, and measures being proposed as part of the on-going code development process. PNNL analyzed these measures using whole building energy models for selected prototype commercial buildings and multifamily buildings representing buildings in New York. Section 2 of this report describes the analysis methodology, including the building types and construction area weights update for this analysis, the baseline, and the method to conduct the energy saving analysis. Section 3 provides detailed specifications of the EEMs and bundles. Section 4 summarizes the results of individual EEMs and EEM bundles by building type, energy end-use and climate zone. Appendix A documents detailed descriptions of the selected prototype buildings. Appendix B provides energy end-use breakdown results by building type for both the baseline code and stretch code in all climate zones.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

DOE OSTI2014

Stockbridge Munsee Community Health and Wellness Center and the Mohican Family Center Renewable Energy and Energy Efficiency Feasibility Study

The results of the Renewable Energy and Energy Efficiency Feasibility Study of Stockbridge Munsee Community’s Health and Wellness Center (HWC) indicate that a variety of renewable energy options and energy conservation measures (ECMs) exist for the facility. A requirement of the Request for Proposal for this study was to assess renewable energy options that could offset 30 to 100 percent of the HWC’s energy use. This study identifies that a geothermal system is the most cost effective renewable energy option available to decrease the HWC’s energy consumption by 30 to 100 percent. Currently the HWC performs in the lowest 8 percent of buildings in its building category, as scored in the EPA portfolio manager benchmarking tool. Multiple ECM opportunities have been identified with paybacks of less than five years to yield an estimated 25-percent decrease in annual energy consumption. The ECMs within this payback period are estimated to save $26,800 per year with an implementation cost of just $4,650 (0.2 year payback). For the Mohican Family Center document: The results of the Renewable Energy and Energy Efficiency Feasibility Study of Stockbridge Munsee Community’s Mohican Family Center (MFC) indicate that a variety of renewable energy options and energy conservation measures (ECMs) exist for the facility. A requirement of the Request for Proposal for this study was to assess renewable energy options that could offset 30 to 100 percent of the MFC’s energy use. This study identifies that a geothermal system is the most cost effective renewable energy option available to decrease the MFC’s energy consumption by 30 to 100 percent. Currently the MFC performs better than 80 percent of buildings in its building category, as scored in the EPA portfolio manager benchmarking tool. Multiple ECM opportunities have been identified with short term paybacks to yield an estimated 13-percent decrease in energy consumption. The ECMs within this payback period are estimated to save $3,100 per year with an implementation cost of under $20,000.

09 BIOMASS FUELS↗

DOE OSTI2018

Material and Energy Efficiency: A Framework for Broader Analysis of Energy Use in the U.S. Economy

Energy efficiency analysis has focused predominantly on reducing energy at its point of use by individual components, processes, or products. Efforts to address the energy embodied in materials through strategies and technologies that reduce raw material production - while maintaining the function and use of materials - offer a complementary and expansive approach to traditional energy efficiency analysis. The U.S. Department of Energy (DOE) energy analysis community currently lacks analytical tools that are appropriate for 1) estimating on a product and economy-wide basis energy efficiency potential achieved through material efficiency strategies and 2) evaluating how these new strategies may complement existing energy efficiency efforts. The goal of this report is to describe a standardized analysis framework that would enable calculation of embodied and direct energy and the estimation of energy reduction potential achieved through changes in material use. The proposed framework meets this functionality by spanning the entire U.S. economy, including international trade flows; capturing material and energy use in products and services from raw material extraction to retirement; maintaining material and energy balances; and adjusting dynamically to absolute and relative changes in materials and energy use. The framework is composed of two main elements: a dynamic hybrid input-output (IO) model and a material energy identity. The hybrid IO model defines recipes for material and energy flows in physical (e.g., British thermal units [Btus] and tons) and monetary units, and allows for dynamic adjustments to the amount of materials and energy used. The second element of the analytical framework, the material energy identity, acts as a way of identifying and organizing energy and material efficiency strategies, which are then implemented and analyzed in the hybrid IO model. The report also provides a simple example application of the proposed framework, which illustrates the concept of reducing energy use through changes to material efficiency.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

DOE OSTI2018

Zero Energy University Campuses: A 2018 Progress Update on Reaching Campus Energy Goals: Preprint

Many universities have aggressive energy-reduction and climate action plans. To reach these goals, leading universities have developed a suite of common energy-efficiency and renewable generation strategies. In this paper, we present a common set of approaches across the following areas: zero energy campus definitions and planning, best practices for including energy targets in new construction procurement contracts and design guidelines, implementing pilot new construction zero energy projects, aggressively implementing best-in-class laboratory energy-efficiency strategies, planning for and optimizing on-site and off-site renewable energy projects, and high-performance district energy systems. Best practices are compiled from various experiences, including programs funded by the U.S. Department of Energy, Energy Efficiency and Renewable Energy program. The summary of these best practices is to reduce campus energy use and then meet the remaining campus energy needs with renewable energy. The fivestep process to developing and implementing campus energy-reduction plans is described: 1) determine baseline energy consumption, 2) analyze technology options, 3) develop a plan and set priorities, 4) implement the plan, and 5) evaluate progress. The process follows a logical hierarchy of actions to evaluate options by energy sector and set specific targets. It encompasses all energy systems on campus, recognizing that campus-wide measures have increased potential for reducing energy use. Common strategies are explained along with examples and results.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

DOE OSTI2018

Zero Energy University Campuses: A 2018 Progress Update on Reaching Campus Energy Goals

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

DOE OSTI2013

U.S. Department of Energy Pacific Region Clean Energy Application Center (PCEAC)

The U.S. Department of Energy Pacific Region Clean Energy Application Center (PCEAC) was formed in 2009 by the U.S. Department of Energy (DOE) and the California Energy Commission to provide education, outreach, and technical support to promote clean energy -- combined heat and power (CHP), district energy, and waste energy recovery (WHP) -- development in the Pacific Region. The region includes California, Nevada, Hawaii, and the Pacific territories. The PCEAC was operated as one of nine regional clean energy application centers, originally established in 2003/2004 as Regional Application Centers for combined heat and power (CHP). Under the Energy Independence and Security Act of 2007, these centers received an expanded charter to also promote district energy and waste energy recovery, where economically and environmentally advantageous. The centers are working in a coordinated fashion to provide objective information on clean energy system technical and economic performance, direct technical assistance for clean energy projects and additional outreach activities to end users, policy, utility, and industry stakeholders. A key goal of the CEACs is to assist the U.S. in achieving the DOE goal to ramp up the implementation of CHP to account for 20% of U.S. generating capacity by 2030, which is estimated at a requirement for an additional 241 GW of installed clean technologies. Additional goals include meeting the Obama Administration goal of 40 GW of new CHP by 2020, key statewide goals such as renewable portfolio standards (RPS) in each state, California’s greenhouse gas emission reduction goals under AB32, and Governor Brown’s “Clean Energy Jobs Plan” goal of 6.5 GW of additional CHP over the next twenty years. The primary partners in the PCEAC are the Department of Civil and Environmental Engineering and the Energy and Resources Group (ERG) at UC Berkeley, the Advanced Power and Energy Program (APEP) at UC Irvine, and the Industrial Assessment Centers (IAC) at San Diego State University and San Francisco State University. The center also worked with a wide range of affiliated groups and industry, government, NGO, and academic stakeholders to conduct a series of CHP education and outreach, project technical support, and related activities for the Pacific region. Key PCEAC tasks have included: - Preparing, organizing and conducting educational seminars on various aspects of CHP - Conducting state baseline assessments for CHP - Working with state energy offices to prepare state CHP action plans - Providing technical support services including CHP/district energy project feasibility screenings - Working with state agencies on CHP policy development - Developing additional CHP educational materials The primary specific services that PCEAC has offered include: - A CHP “information clearinghouse “ website: http://www.pacificcleanenergy.org - Site evaluations and potential projects screenings - Assessment of CHP status, potential, and key issues for each state - Information and training workshops - Policy and regulatory guidance documents and other interactions These services were generally offered at no cost to client groups based on the DOE funding and additional activities supported by the California Energy Commission, except for the in-kind staff resources needed to provide input data and support to PCEAC assessments at host sites. Through these efforts, the PCEAC reached thousands of end-users and directly worked with several dozen organizations and potential CHP “host sites” from 2009-2013. The major activities and outcomes of PCEAC project work are described.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

DOE OSTI2018

Final Energy Savings Analysis of the Proposed NYStretch-Energy Code 2018

This study was conducted by the Pacific Northwest National Laboratory (PNNL) in support of the stretch energy code development led by the New York State Energy Research and Development Authority (NYSERDA). In 2017 NYSERDA developed its 2016 Stretch Code Supplement to the 2016 New York State Energy Conservation Construction Code (hereinafter referred to as “NYStretch-Energy”). NYStretch-Energy is intended as a model energy code for statewide voluntary adoption that anticipates other code advancements culminating in the goal of a statewide Net Zero Energy Code by 2028. Since then, NYSERDA continues to develop the NYStretch-Energy Code 2018 edition (NYSERDA 2018). To support the effort, PNNL conducted energy simulation analysis to quantify the energy savings of proposed commercial provisions of the NYStretch-Energy Code 2018 in New York. The focus of this project is to significantly improve the energy efficiency over existing commercial model energy codes. A key requirement of the proposed stretch code is that it be ‘adoptable’ as an energy code, meaning that it must align with current code scope and limitations, and primarily impact building components that are currently regulated by local building departments. It is largely limited to prescriptive measures, which are what most building departments and design projects are most familiar with. This report describes a set of energy-efficiency measures (EEMs) that demonstrate significant energy savings over ANSI/ASHRAE/IES Standard 90.1-2013 (ASHRAE 2013) across a broad range of commercial building types and all three climate zones in New York. In collaboration with New Building Institute, the EEMs were developed from national model codes and standards, high-performance building codes and standards, regional energy codes, and measures being proposed as part of the on-going code development process. PNNL analyzed these measures using whole building energy models for selected prototype commercial buildings and multifamily buildings representing buildings in New York.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

DOE OSTI2018

Moving K-12 Zero Energy Schools to the Mainstream: Establishing Design Guidelines and Energy Targets: Preprint

K-12 school buildings are ideal candidates to lead the market shift from buildings that consume energy to buildings that produce as much renewable energy as they use, and there are now resources available to guide owners and project teams as they make that shift. Chief among them is the Advanced Energy Design Guide for K-12 School Buildings: Achieving Zero Energy (K-12 ZE AEDG). Starting with a feasibility study to prove that zero energy schools were possible, a committee of industry experts used extensive energy modeling to create a set of energy use intensity allowances for school buildings such that on-site renewable energy could meet the buildings' energy loads . These energy targets were compared with the energy use intensities of a limited number of schools that have achieved very high levels of energy performance. The allowances represent a 'zero energy ready' (rather than zero energy) school, because in many situations the ability to use on-site renewable sources is limited by utilities, policies, or economics. From these targets, the guidance for achieving a zero energy school was created and developed into the K-12 ZE AEDG, which covers the process of designing and building zero energy schools from the perspective of an owner and a project team. The K-12 ZE AEDG advocates setting an absolute energy target before design begins. The K-12 ZE AEDG also contains practical, cost-effective strategies for achieving the energy target and outreach approaches and disseminating these market-friendly strategies to design and school owner communities.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

DOE OSTI2018

Moving K-12 Zero Energy Schools to the Mainstream: Establishing Design Guidelines and Energy Targets

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

DOE OSTI2020

Developing a common approach for classifying building stock energy models

Buildings contribute 40% of global greenhouse gas emissions; therefore, strategies that can substantially reduce emissions from the building stock are key components of broader efforts to mitigate climate change and achieve sustainable development goals. Models that represent the energy use of the building stock at scale under various scenarios of technology deployment have become essential tools for the development and assessment of such strategies. Within the past decade, the capabilities of building stock energy models have improved considerably, while model transferability and sharing has increased. Given these advancements, a new scheme for classifying building stock energy models is needed to facilitate communication of modeling approaches and the handling of important model dimensions. In this article, we present a new building stock energy model classification framework that leverages international modeling expertise from the participants of the International Energy Agency's Annex 70 on Building Energy Epidemiology. Drawing from existing classification studies, here we propose a multi-layer quadrant scheme that classifies modeling techniques by their design (top-down or bottom-up) and degree of transparency (black-box or white-box); hybrid techniques are also addressed. The quadrant scheme is unique from previous classification approaches in its non-hierarchical organization, coverage of and ability to incorporate emerging modeling techniques, and treatment of additional modeling dimensions. The new classification framework will be complemented by a reporting protocol and online registry of existing models as part of ongoing work in Annex 70 to increase the interpretability and utility of building stock energy models for energy policy making.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

DOE OSTI2016

From Zero Energy Buildings to Zero Energy Districts

Some U.S. cities are planning advanced districts that have goals for zero energy, water, waste, and/or greenhouse gas emissions. From an energy perspective, zero energy districts present unique opportunities to cost-effectively achieve high levels of energy efficiency and renewable energy penetration across a collection of buildings that may be infeasible at the individual building scale. These high levels of performance are accomplished through district energy systems that harness renewable and wasted energy at large scales and flexible building loads that coordinate with variable renewable energy supply. Unfortunately, stakeholders face a lack of documented processes, tools, and best practices to assist them in achieving zero energy districts. The National Renewable Energy Laboratory (NREL) is partnering on two new district projects in Denver: the National Western Center and the Sun Valley Neighborhood. We are working closely with project stakeholders in their zero energy master planning efforts to develop the resources needed to resolve barriers and create replicable processes to support future zero energy district efforts across the United States. Initial results of these efforts include the identification and description of key zero energy district design principles (maximizing building efficiency, solar potential, renewable thermal energy, and load control), economic drivers, and master planning principles. The work has also resulted in NREL making initial enhancements to the U.S. Department of Energy's open source building energy modeling platform (OpenStudio and EnergyPlus) with the long-term goal of supporting the design and optimization of energy districts.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

DOE OSTI2016

Marine Hydrokinetic Energy Site Identification and Ranking Methodology Part I: Wave Energy

Marine hydrokinetic energy is a promising and growing piece of the renewable energy sector that offers high predictability and additional energy sources for a diversified energy economy. This report investigates the market opportunities for wave energy along the U.S. coastlines. It is part one of a two-part investigation into the United State's two largest marine hydrokinetic resources (wave and tidal). Wave energy technology is still an emerging form of renewable energy for which large-scale, grid-connected project costs are currently poorly defined. Ideally, device designers would like to know the resource conditions at economical project sites so they can optimize device designs. On the other hand, project developers need detailed device cost data to identify sites where projects are economical. That is, device design and siting are, to some extent, a coupled problem. This work describes a methodology for identifying likely deployment locations based on a set of criteria that wave energy experts in industry, academia, and national laboratories agree are likely to be important factors for all technology types. This work groups the data for the six criteria into 'locales' that are defined as the smaller of either the local transmission grid or a state boundary. The former applies to U.S. islands (e.g., Hawaii, American Samoa) and rural villages (e.g., in Alaska); the latter applies to states in the contiguous United States. These data are then scored from 0 to 10 according to scoring functions that were developed with input from wave energy industry and academic experts. The scores are aggregated using a simple product method that includes a weighting factor for each criterion. This work presents two weighting scenarios: a long-term scenario that does not include energy price (weighted zero) and a near term scenario that includes energy price. The aggregated scores are then used to produce ranked lists of likely deployment locales. In both scenarios, Hawaii and the Pacific Northwest (northern California, Oregon, and Washington) rank at the top of the lists. Hawaii ranks highest in the near-term scenario because it has high energy costs. In the long-term scenario, Oregon ranks highest because it has a large market and an energetic resource. Several East Coast states and Puerto Rico are also identified as potential wave energy deployment sites if technological innovations make it possible to efficiently generate electricity from the modest resource there. There are also several small-market sites in Alaska and U.S. Pacific Islands that rank particularly well in the near-term analysis due to their high energy prices. These locations may represent opportunities to demonstrate economical wave energy conversion as a stepping-stone to larger markets. Several factors that will affect wave project costs and siting have not been considered here -- including permitting constraints, conflicting use, seasonal resource variability, extreme event likelihood, and distance to ports -- because consistent data are unavailable or technology-independent scoring could not be identified. As the industry continues to mature and converge around a subset of device archetypes with well-defined costs, more precise investigations of project siting that include these factors will be possible. For now, these results provide a high-level guide pointing to the regions where markets and resource will one day support commercial wave energy projects.

16 TIDAL AND WAVE POWER↗

DOE OSTI2015

Study of energy conversion and partitioning in the magnetic reconnection layer of a laboratory plasma

While the most important feature of magnetic reconnection is that it energizes plasma particles by converting magnetic energy to particle energy, the exact mechanisms by which this happens are yet to be determined despite a long history of reconnection research. Recently, we have reported our results on the energy conversion and partitioning in a laboratory reconnection layer in a short communication [Yamada et al., Nat. Commun. 5, 4474 (2014)]. The present paper is a detailed elaboration of this report together with an additional dataset with different boundary sizes. Our experimental study of the reconnection layer is carried out in the two-fluid physics regime where ions and electrons move quite differently. We have observed that the conversion of magnetic energy occurs across a region significantly larger than the narrow electron diffusion region. A saddle shaped electrostatic potential profile exists in the reconnection plane, and ions are accelerated by the resulting electric field at the separatrices. These accelerated ions are then thermalized by re-magnetization in the downstream region. A quantitative inventory of the converted energy is presented in a reconnection layer with a well-defined, variable boundary. We have also carried out a systematic study of the effects of boundary conditions on the energy inventory. This study concludes that about 50% of the inflowing magnetic energy is converted to particle energy, 2/3 of which is ultimately transferred to ions and 1/3 to electrons. Assisted by another set of magnetic reconnection experiment data and numerical simulations with different sizes of monitoring box, it is also observed that the observed features of energy conversion and partitioning do not depend on the size of monitoring boundary across the range of sizes tested from 1.5 to 4 ion skin depths.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗

DOE OSTI2013

Energy implications of mechanical and mechanical–biological treatment compared to direct waste-to-energy

Highlights: • Compared systems achieve primary energy savings between 34 and 140 MJ{sub primary}/100 MJ{sub input} {sub waste.} • Savings magnitude is foremost determined by chosen primary energy and materials production. • Energy consumption and process losses can be upset by increased technology efficiency. • Material recovery accounts for significant shares of primary energy savings. • Direct waste-to-energy is highly efficient if cogeneration (CHP) is possible. - Abstract: Primary energy savings potential is used to compare five residual municipal solid waste treatment systems, including configurations with mechanical (MT) and mechanical–biological (MBT) pre-treatment, which produce waste-derived fuels (RDF and SRF), biogas and/or recover additional materials for recycling, alongside a system based on conventional mass burn waste-to-energy and ash treatment. To examine the magnitude of potential savings we consider two energy efficiency levels (state-of-the-art and best available technology), the inclusion/exclusion of heat recovery (CHP vs. PP) and three different background end-use energy production systems (coal condensing electricity and natural gas heat, Nordic electricity mix and natural gas heat, and coal CHP energy quality allocation). The systems achieved net primary energy savings in a range between 34 and 140 MJ{sub primary}/100 MJ{sub input} {sub waste}, in the different scenario settings. The energy footprint of transportation needs, pre-treatment and reprocessing of recyclable materials was 3–9.5%, 1–18% and 1–8% respectively, relative to total energy savings. Mass combustion WtE achieved the highest savings in scenarios with CHP production, nonetheless, MBT-based systems had similarly high performance if SRF streams were co-combusted with coal. When RDF and SRF was only used in dedicated WtE plants, MBT-based systems totalled lower savings due to inherent system losses and additional energy costs. In scenarios without heat recovery, the biodrying MBS-based system achieved the highest savings, on the condition of SRF co-combustion. As a sensitivity scenario, alternative utilisation of SRF in cement kilns was modelled. It supported similar or higher net savings for all pre-treatment systems compared to mass combustion WtE, except when WtE CHP was possible in the first two background energy scenarios. Recovery of plastics for recycling before energy recovery increased net energy savings in most scenario variations, over those of full stream combustion. Sensitivity to assumptions regarding virgin plastic substitution was tested and was found to mostly favour plastic recovery.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

DOE OSTI2017

Energy Conversion Loop: Process Heat Applications of Hybrid Energy Systems

Climate change due to greenhouse gas (GHG) emissions has prompted a shift from fossil fuel energy to other sources for electricity production such as nuclear, solar or wind. These alternatives since no GHG is produced, and no fossil fuels are burned. Both nuclear and other renewable energy sources are recognized as reliable technologies in the United States and around the world. However, they all have a unique set of challenges. Two of the most common renewable energy sources are solar and wind. A particular shortcoming of these two options is the variability of the energy produced; that is they are highly dependent on weather. Many times wind and/or solar power systems are not able to meet the electric demand during peak times. Replacing fossil fuels with nuclear energy is an option (non fossil fuel) for clean energy production. Two primary challenges with using nuclear energy are; wasted heat energy and the lack of load following capabilities. First, heat energy is wasted in the production stream from steam that is created while cooling the core of a nuclear reactor. This steam is initially used in turbines where the electricity is produced. However, once the steam passes through the turbines it is cooled, re-condensed to water, and reused. Large amounts of heat energy are released in the form of heat to the environment (either to the atmosphere or as waste water) and go unused. Secondly, nuclear energy is primarily a baseload power producer - the power output does not fluctuate with power demands, or is not load following. A nuclear hybrid energy system (NHES) may be a solution to the two issues mentions above. Traditional hybrid energy systems (HES) are a combination of two or more energy producers working together to create different energy commodities such as fuel or electricity. To create a NHES, normal use of the reactor for electricity production is combined with renewable power sources to meet the peak power demand of the grid. When electricity demand is high the renewable source and NPP are used in conjunction to meet the demand. When the electricity demand is low the renewable power is used to produce electricity while the NPP operates at full capacity. Rather than sending the excess heat to the cooling towers the excess energy created by the NPP (heat) is diverted to another industrial process.There is no need to decrease the power coming out of the NPP. This research proposal addresses harvesting unused thermal energy from a NPP during normal operations and in times of low power demand.

22 GENERAL STUDIES OF NUCLEAR REACTORS↗

DOE OSTI2025

Potential Effects of Climate Change and Solar Radiation Modification on Renewable Energy Resources

Solar radiation modification (SRM) is a possible deliberate approach to decrease or reflect incoming solar radiation with the goal of reducing global temperatures, which have increased over the last decades due to high atmospheric greenhouse gas concentrations. Stratospheric aerosol injection, specifically, has shown potential for successfully reducing global temperatures in climate model simulations. Despite the growing literature in the areas of climate change and SRM, their combined effects on renewable energy generation, a climate change mitigation strategy, have not been addressed. In this review paper, we synthesize previous literature on the possible effects of climate change and SRM on renewable energy resources (i.e., wind energy, solar energy, biomass energy, and hydropower), review the status of climate change and SRM research, and explore potential effects of SRM on renewable energy primarily in the Continental United States (CONUS), but with global perspectives as well. We discuss the research challenges and impacts of SRM on renewable energy and conclude by discussing the potential implications of SRM for renewables for SRM governance and policy. This work is not advocating for or against SRM. It is highlighting an important potential impact for future decision makers.

Kumler, Andrew [National Renewable Energy Laborato↗

DOE OSTI2014

Technical Note: Influence of the phantom material on the absorbed-dose energy dependence of the EBT3 radiochromic film for photons in the energy range 3 keV–18 MeV

Purpose: Water is the reference medium for radiation therapy dosimetry, but for film dosimetry it is more practical to use a solid phantom. As the composition of solid phantoms differs from that of water, the energy dependence of film exposed within solid phantoms may also differ. The energy dependence of a radiochromic film for a given beam quality Q (energy for monoenergetic beams) has two components: the intrinsic energy dependence and the absorbed-dose energy dependence f(Q), the latter of which can be calculated through a Monte Carlo simulation of radiation transport. The authors used Monte Carlo simulations to study the influence of the phantom material on the f(Q) of the EBT3 radiochromic film (Ashland Specialty Ingredients, Wayne, NJ) for photon beams with energies between 3 keV and 18 MeV. Methods: All simulations were carried out with the general-purpose Monte Carlo code PENELOPE 2011. The geometrical model consisted of a cylindrical phantom, with the film positioned at different depths depending on the initial photon energy. The authors simulated monoenergetic parallel photon beams and x-ray beams from a superficial therapy system. To validate their choice of simulation parameters, they also calculated f(Q) for older film models, EBT and EBT2, comparing with published results. In addition to water, they calculated f(Q) of the EBT3 film for solid phantom materials commonly used for film dosimetry: RW1 and RW3 (PTW-Freiburg, Freiburg, Germany), Solid Water (Gammex-RMI, Madison, WI), and PMMA. Finally, they combined their calculated f(Q) with published overall energy response data to obtain the intrinsic energy dependence of the EBT3 film in water. Results: The calculated f(Q) for EBT and EBT2 films was statistically compatible with previously published data. Between 10 keV and 18 MeV, the variation found in f(Q) of the EBT3 film for water was within 2.3%, with a standard statistical uncertainty less than 1%. If the quantity dose-to-water in the phantom is considered, which is the common practice in radiation dosimetry, the maximum difference of energy dependence for the solid phantoms with respect to water is about 6%, at an energy of 50 keV. Conclusions: The EBT3 film shows a reasonably constant absorbed-dose energy dependence when irradiated in water. If the dose-to-water in the phantom is considered, the maximum difference of EBT3 film energy dependence with the solid phantoms studied with respect to water is about 6% (at an energy of 50 keV). The reported overall energy dependence of the EBT3 film in water at energies below 100 keV is mainly due to the intrinsic energy dependence.

07 ISOTOPE AND RADIATION SOURCES↗