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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 307 records · Page 17

Texas Clean Energy Project: Decision Point Application, Section 2: Topical Report - Phase 1, February 2010-October 2013

Summit Texas Clean Energy, LLC (STCE) is developing the Texas Clean Energy Project (TCEP or the Project) to be located near Penwell, Texas. The TCEP will include an Integrated Gasification Combined Cycle (IGCC) power plant with a nameplate capacity of 400 megawatts electric (MWe), combined with the production of urea fertilizer and the capture, utilization and storage of carbon dioxide (CO 2 ) sold commercially for regional use in enhanced oil recovery (EOR) in the Permian Basin of west Texas. The TCEP will utilize coal gasification technology to convert Powder River Basin subbituminous coal delivered by rail from Wyoming into a synthetic gas (syngas) that will be cleaned and further treated so that at least 90 percent of the overall carbon entering the IGCC facility will be captured. The clean syngas will then be divided into two highhydrogen (H 2 ) concentration streams, one of which will be combusted as a fuel in a combined cycle power block for power generation and the other converted into urea fertilizer for commercial sale. The captured CO 2 will be divided into two streams: one will be used in producing the urea fertilizer and the other will be compressed for transport by pipeline for offsite use in EOR and permanent underground sequestration. The TCEP was selected by the U.S. Department of Energy (DOE) Office of Fossil Energy (FE) for cost-shared co-funded financial assistance under Round 3 of its Clean Coal Power Initiative (CCPI). A portion of this financial assistance was budgeted and provided for initial development, permitting and design activities. STCE and the DOE executed a Cooperative Agreement dated January 29, 2010, which defined the objectives of the Project for all phases. During Phase 1, STCE conducted and completed all objectives defined in the initial development, permitting and design portions of the Cooperative Agreement. This topical report summarizes all work associated with the project objectives, and additional work required to complete the financing of the Project. In general, STCE completed project definition, a front-end, engineering and design study (FEED), applied for and received its Record of Decision (ROD) associated with the NEPA requirements summarized in a detailed Environmental Impact Statement. A topical report covering the results of the FEED is the subject of a separate report submitted to the DOE on January 26, 2012. References to the FEED report are contained herein. In August 2013, STCE executed fixed-price turnkey EPC contracts and previously, in December 2011 a long-term O&M agreement, with industry-leading contractors. Other work completed during Phase 1 includes execution of all commercial input and offtake agreements required for project financing. STCE negotiated long-term agreements for power, CO 2 and urea offtake. A contract for the purchase of coal feedstock from Cloud Peak Energy’s Cordero Rojo mine was executed, as well as necessary agreements (supplementing the tariff) with the Union Pacific Railroad (UPRR) for delivery of the coal to the TCEP site. STCE executed firm agreements for natural gas transportation with ONEOK for long-term water supply with a private landowner. In addition, STCE secured options for critical easements and rights-of-way, completed and updated a transmission study, executed an interconnection agreement and has agreed a target October 31, 2013 financial closing date with debt and conventional and tax equity.

Mattes, Karl↗

Stem Inc. SunShot Incubator Program Final Technical Report

In this Energy Storage Control Algorithms project, Stem sought to develop tools and control algorithms to increase the value and reduce balance-of-system and grid integration costs associated with adding distributed solar generation to the grid. These advances fell under the headings SolarScope and SolarController. Stem sought to create initial market traction with a fully commercialized product for the solar industry to size storage systems (SolarScope) as well as a solar intermittency-mitigation framework for utilities (SolarController) in the course of the project. The company sought to align strategic growth plans and enable the rollout of the products to broader audiences in multiple geographic regions by leveraging the major solar companies in the national market as partners. Both final products were both intended to be commercialized. They are: SolarScope: Analysis tool to identify viable PV + storage projects and thereby expedite the sales and interconnection processes. SolarScope combines customer load data, PV production estimates, utility rate tariff, and simulated storage into a simple user interface for PV developers. Developers can easily identify viable solar + storage sites without the need for complex and time consuming, site-by-site spreadsheet modeling. SolarContoller: Tool to autonomously dispatch distributed storage in order to mitigate voltage fluctuation and reduce curtailment. SolarController co-optimizes, in real time, storage dispatch for circuit stability and curtailment reduction, enabling higher penetrations of PV. SolarController is automated, not requiring utility dispatch or management, as Stem hardware senses grid voltage, frequency, customer load, PV production, and power factor. In the end the two products met with different outcomes. SolarScope was tested by potential users, and continues to be used as a foundational platform for partnership with key solar industry partners. SolarController, on the other hand, was successful in lab testing but was not commercialized due to a lack of marketability and lack of interested customer base. Together the development of these two products marked a material step forward for Stem; and a new milestone along the pathway of integration for the solar and storage industries. SolarScope is leading to real, out-of-the-lab project development in storage + solar for the commercial customer sector. Meanwhile SolarController has opened the eyes of regulators and utility executives alike to the potential of distributed solar and by doing so, has moved the conversation forward for the integration of distributed energy resources more broadly on the grid.

25 ENERGY STORAGE↗

Energizing Government Decision-Makers with the Facts on Solar Technology, Policy, and Integration

The Solar Technical Assistance Team (STAT) is a network of solar technology and implementation experts who provide timely, unbiased expertise to assist policymakers and regulators in making informed decisions about solar programs and policies. Government officials can submit requests directly to the STAT for technical assistance. STAT then partners with experts in solar policy, regulation, finance, technology, and other areas to deliver accurate, up-to-date information to state and local decision makers. The STAT responds to requests on a wide range of issues -- including, but not limited to, feed-in tariffs, renewable portfolio standards, rate design, program design, workforce and economic impacts of solar on jurisdictions, and project financing.

14 SOLAR ENERGY↗

A Transparent Framework for Evaluating the Effects of DGPV on Distribution System Costs

Assessing the costs and benefits of distributed photovoltaic generators (DGPV) to the power system and electricity consumers is key to determining appropriate policies, tariff designs, and power system upgrades for the modern grid. We advance understanding of this topic by providing a transparent framework, terminology, and data set for evaluating distribution system upgrade costs, line losses, and interconnection costs as a function of DGPV penetration level.

24 POWER TRANSMISSION AND DISTRIBUTION↗

Distributed Energy Resources Customer Adoption Model - Graphical User Interface, Version 2.1.8

The DER-CAM Graphical User Interface has been redesigned to consist of a dynamic tree structure on the left side of the application window to allow users to quickly navigate between different data categories and views. Views can either be tables with model parameters and input data, the optimization results, or a graphical interface to draw circuit topology and visualize investment results. The model parameters and input data consist of tables where values are assigned to specific keys. The aggregation of all model parameters and input data amounts to the data required to build a DER-CAM model, and is passed to the GAMS solver when users initiate the DER-CAM optimization process. Passing data to the GAMS solver relies on the use of a Java server that handles DER-CAM requests, queuing, and results delivery. This component of the DER-CAM GUI can be deployed either locally or remotely, and constitutes an intermediate step between the user data input and manipulation, and the execution of a DER-CAM optimization in the GAMS engine. The results view shows the results of the DER-CAM optimization and distinguishes between a single and a multi-objective process. The single optimization runs the DER-CAM optimization once and presents the results as a combination of summary charts and hourly dispatch profiles. The multi-objective optimization process consists of a sequence of runs initiated by the GUI, including: 1) CO2 minimization, 2) cost minimization, 3) a user defined number of points in-between objectives 1) and 2). The multi-objective results view includes both access to the detailed results of each point generated by the process as well as the generation of a Pareto Frontier graph to illustrate the trade-off between objectives. DER-CAM GUI 2.1.8 also introduces the ability to graphically generate circuit topologies, enabling support to DER-CAM 5.0.0. This feature consists of: 1) The drawing area, where users can manually create nodes and define their properties (e.g. point of common coupling, slack bus, load) and connect them through edges representing either power lines, transformers, or heat pipes, all with user defined characteristics (e.g., length, ampacity, inductance, or heat loss); 2) The tables, which display the user-defined topology in the final numerical form that will be passed to the DER-CAM optimization. Finally, the DER-CAM GUI is also deployed with a database schema that allows users to provide different energy load profiles, solar irradiance profiles, and tariff data, that can be stored locally and later used in any DER-CAM model. However, no real data will be delivered with this version.

Ewald, Friedrich↗

Geothermal-Enabled Zero Energy Community: A Techno-Economic Design Study to Address Cold-Climate Challenges

In northern climates, developing a zero-energy community is increasingly costly. Building loads are higher, thanks to the colder weather, and solar PV is both less effective, due to lower solar incidence, and misalignment with the buildings' energy needs (summer production, winter demands). We present a novel application for geothermal energy production in support of a zero-energy community, combining appropriate energy efficiency (demand design), geothermal production (supply design), and asset dispatch as an integrated technoeconomic package. This poster presents the process used to explore this system integration challenge, initial results, and discusses some of the technical opportunities for increasing the community-scale adoption of geothermal as an electric and thermal resource. Results indicate that under certain conditions, community-scale geothermal resources are quite competitive with today's grid tariffs and with PV, showing an LCOE within $0.01/kWh before consideration of important grid modernization factors such as resiliency and reliability.

15 GEOTHERMAL ENERGY↗

Geothermal-Enabled Zero Energy Electric Community: An Integrated System Design Study

In northern climates, developing a zero-energy community is increasingly costly. Building loads are higher, thanks to the colder weather, and solar PV is both less effective, due to lower solar incidence, and misalignment with the buildings' energy needs (summer production, winter demands). We present a novel application for geothermal energy production in support of a zero-energy community, combining appropriate energy efficiency (demand design), geothermal production (supply design), and asset dispatch as an integrated technoeconomic package. This poster presents the process used to explore this system integration challenge, initial results, and discusses some of the technical opportunities for increasing the community-scale adoption of geothermal as an electric and thermal resource. Results indicate that under certain conditions, community-scale geothermal resources are quite competitive with today's grid tariffs and with PV, showing an LCOE within $0.01/kWh before consideration of important grid modernization factors such as resiliency and reliability.

15 GEOTHERMAL ENERGY↗

Geothermal-Enabled Zero Energy Electric Community -- An Integrated System Design Study: Preprint

In northern climates, developing a zero-energy community is increasingly costly. Building loads are higher, thanks to the colder weather, and solar PV is both less effective, due to lower solar incidence, and misalignment with the buildings' energy needs (summer production, winter demands). We present a novel application for geothermal energy production in support of a zero-energy community, combining appropriate energy efficiency (demand design), geothermal production (supply design), and asset dispatch as an integrated technoeconomic package. This paper presents the process used to explore this system integration challenge, initial results, and discusses some of the technical opportunities for increasing the community-scale adoption of geothermal as an electric and thermal resource. Results indicate that under certain conditions, community-scale geothermal resources are quite competitive with today's grid tariffs and with PV, showing an LCOE within $0.01/kWh before consideration of important grid modernization factors such as resiliency and reliability.

15 GEOTHERMAL ENERGY↗

Solar + Storage: A Guide for Local Governments

The pairing of solar energy and energy storage technologies presents several opportunities of increased value for communities. This webinar provided an introduction into the topic including markets, tariffs, benefits, and interconnection agreements. It then included a deeper study of permitting considerations for communities such as safety, resources and existing challenges. Lastly, SolSmart communities with solar and storage experience are highlighted.

14 SOLAR ENERGY↗

Quantifying Technical Diversity Benefits of Wind as a Distributed Energy Resource

Distributed energy resources are increasingly used in power distribution systems and microgrids to supply cost competitive power, improve resilience, and provide a host of grid services. Diversifying variable renewable resources (e.g., by combining wind with solar) can increase energy usage efficiency and improve system resilience. However, when grid optimization and resilience studies consider multiple renewable resources, diversity benefits are usually captured only implicitly in the results of location-specific economic optimization. In this paper, metrics are introduced to express the technical value of resource diversity independent of jurisdiction-specific market structures. Specifically, marginal energy usage efficiency metrics are developed to quantify the ability of new distributed generation to produce useful energy and an incremental sustainable ride through metric is developed to express improvement in grid outage ride through capability. While there are economic implications for each of these metrics, the metrics themselves are technically-driven and could be used as components of a technical figure of merit that could be used to inform policy actions, such as development of resource-specific incentives and time-of-use tariff designs. Each of these metrics is demonstrated using balance-of-energy simulations that highlight the benefits of improving resource diversity.

Reiman, Andrew P.↗

The Impact of Behind-the-Meter Heterogeneous Distributed Energy Resources on Distribution Grids: Preprint

The increasing integration of distributed energy resources (DERs) on the electric grid brings new challenges and opportunities for utility grid operations. With the rapid deployment of DERs, there is emerging interest in integrating these controllable devices with utility operations at all levels for monitoring and management. Different types of DERs such as Photovoltaics (PV), energy storage, electric vehicles (EVs), etc. have varying effects on the grid based on how and where they are deployed. Again, the DER deployment and its impact are network-dependent, while the traditional electric grids were not designed to host DERs. To understand the challenges with increasing behind-the-meter (BTM) DERs and to identify the needs in deploying advanced controls, a comprehensive grid impact study is indispensable. This paper investigates the impacts of integrating a mix of DERs in the utility distribution network in Colorado, U.S. Firstly, BTM DERs at the residential scale including distributed PV; battery energy storage systems (BESS); heating, ventilation, and air-conditioning (HVAC) load; electric water heater (EWH) load; and EVs are modeled. The impacts of integrating these resources on the distribution network are evaluated by conducting time-series simulations for different scenarios considering different days to capture the worst-case conditions. Monte Carlo simulations are conducted to generate the realistic EV charging profile. The voltage issues, substation transformer loadings, and critical nodes in the network are identified with the incorporation of uncoordinated EV charging loads and other DER in the network. This analysis helps visualize the DER impact on the grid, identify the challenges, and provides an insight into the new distribution management and control needs to enable reliable and resilient distribution grid operations. Additionally, further analysis is performed to estimate the daily residential electricity cost with the inclusion of DERs under time-of-use tariffs. The result shows the daily residential electricity cost reduced by 20:7% on average with DERs compared to the case without DERs.

27 ARPA - Advanced Research Projects Agency-Energy↗

Behind the Meter Storage for Electric Vehicle Charging, Electrochemical and Thermal Energy Storage, and Solar Photovoltaic

In response to the potentially large and irregular demand from EVs, along with changing load profiles from buildings with on-site generation, utilities are evaluating multiple options for managing dynamic loads, including time-of-use pricing, demand charges, battery storage, and curtailment of variable generation. Buildings, as well as commercial, public, and workplace EV charging operations, can use a combination of electrochemical battery storage and thermal energy storage coupled with on-site generation to manage energy costs as well as provide resiliency and reliability for EV charging and building energy loads. We are completing a behind the meter storage analysis that focuses on determining the optimal system designs and energy flows for thermal and electrochemical behind the meter storage with on-site solar photovoltaic (PV) generation enabling electric vehicle charging in various climates, building types, and utility rate structures. In completing this analysis, we have developed a tool that combines existing battery models via the System Advisor Model (SAM) and building modeling software via EnergyPlus into a single interface. This tool allows us to simulate a building with a detailed battery model to properly size the battery, thermal energy storage, and solar PV systems to maximize profit for the system owner. This also allows us to assess how the battery degrades under various supervisory control dispatch algorithms to control charging/discharging; we can also see how thermal energy storage is created and used to complement the battery to reduce thermal loads in the building. With this project, we can analyze new batteries that are designed specifically for energy storage, rather than designed to be extremely energy dense for electric vehicle applications, using battery lifetime models from other national labs and the existing SAM battery model, which has detailed lifetime and degradation parameters. We can also assess novel thermal storage technologies by integrating them into the whole building energy simulation program EnergyPlus. Because the model calls both SAM and EnergyPlus, required inputs need to be compatible for both models. These inputs include, on a high-level, the following: weather files, building and electric vehicle load profiles, electricity rate tariff information, and system cost information for the stationary battery, solar PV, and thermal storage system. The various buildings we are studying for this analysis are retail big-box grocery store, commercial office building, fleet vehicle depot and operations facility, multi-family residential, and electric vehicle charging station. For these different applications, the battery and thermal storage will be dispatched differently, and the various technologies are sized differently to optimize cost.

30 DIRECT ENERGY CONVERSION↗

Optimal Efficiency and Operational Cost Savings: A Framework for Automated Rooftop PV Placement

Residential energy consumers are charged based on a utility rate structure, such as net metering or feed-in tariff. To lower consumers' electricity bills, expensive batteries are deployed to reduce the electricity fed from the grid during peak hours. However, strategic photovoltaic (PV) panel placement enables the reduction of operational energy cost while considering the spatial feasibility and efficiency for hosting rooftop PV. In this paper, we present a framework to automatically identify the optimal location of rooftop PV panels on residential buildings. Our framework integrates multiple workflows, including energy and environmental simulation, parametric modeling, and optimization to identify the ideal location of PV panels to balance the demand and supply at a building and community scale. These workflows are linked using the Grasshopper plug-in for Rhinoceros CAD software. The framework includes two different workflows, each satisfying a target for optimal PV placement: (a) maximizing PV panel efficiency, where users aim to maximize energy generation, and (b) minimizing operational energy cost, where "best'' panels are selected considering utility rates for operational energy cost. Our framework is demonstrated in a residential community in Fort Collins, Colorado, to generate the optimal PV placement for each of the two aforementioned targets. Results from the two workflows are compared to illustrate the effect of PV location and orientation on solar energy production efficiency and operational energy cost. The developed workflows are introduced as tools within the Grasshopper plug-in to investigate the solar potential of rooftop PV panels while taking into account factors such as contextual shading, utility rate structures, and buildings' energy demand profiles.

30 DIRECT ENERGY CONVERSION↗

Peak Power Reduction for HVAC Operations in Multi-unit Commercial Buildings

The load profiles of most commercial consumers are characterized by brief periods of very high power consumption followed by intervals of relatively lower demand. In order to flatten commercial load profiles, several power utilities in addition to billing energy consumption, levy a demand charge (DC) on the monthly peak demand. In this work, we consider the problem of joint optimization of energy costs (EC) and DC incurred by a multi-unit building which follows a demand response (DR) program. Despite the non-linear structure of the problem, we show how the optimal solutions can be obtained efficiently using linear programming. We evaluate the performance of the proposed power control scheme for various climate zones in the US. We show that depending on the ambient conditions and the prescribed tariff structure, our strategy can result in savings of up to nearly 19% compared to the baseline.

Raza Naqvi, Syed A.↗

Towards a Techno-Economic Analysis of PCM Integrated Hybrid HVAC Systems

Thermal end uses dominate building energy consumption and are a major driver of peak demand. As heating is electrified, peak electrical power required will surge, prompting a need for innovative HVAC system designs and controls.These designs must incorporate novel technologies at the component level and new integration techniques at the system level. One such possibility involves the addition of thermal energy storage (TES) in heating and cooling equipment using a phase change material (PCM) heat exchanger. Here, thermal energy storage via phase change can be used to shift the HVAC system loads to times of lower electricity cost, reduced carbon intensity, and greater energy efficiency. Most of the current utilization of PCM in buildings involves passive components. By actively controlling when heat is stored and released from PCM, we can optimize the building HVAC system to cost-effectively meet consumer needs with the flexibility to draw on renewable energy resources when they are abundant and available. While this combination of technologies is promising in theory, simulation-based evaluation of a prototype can be difficult due to the modeling requirements at the component level and the large number of possible configurations and operating modes at the system level. To conduct this evaluation, we use the Modelica language for modeling and simulation because it enables users to represent the important physics of the problem, interchange and rearrange components in an efficient manner, and implement a range of control configurations. In this work, we considered three case studies: a portable building, a large commercial retail store, and a multifamily residential apartment unit. Each of these employs a different system design, ranging from a single package vertical unit incorporating PCM to a central plant with independent heat pump, evaporative cooling, and thermal energy storage components. This paper describes the technologies in question, presents modeling at the component and system levels, and demonstrates building energy and demand charge cost savings with local time-of-use tariffs in a hot-dry climate.

Helmns, Dre↗

Transactive Energy Rationing in an Islanded Electric Power System

A battery energy storage system (BESS) has been installed on Nantucket Island to provide service continuity during the N-1 contingency of partial electricity supply interruption from the mainland. During the N-2 contingency of complete interruption from the mainland, most of the loads will have to be disconnected so that a combustion gas turbine (CTG) can supply critical facilities. This work proposes an alternative transactive rationing mechanism that would provide some service to all of the loads, and still fully serve the critical loads, through market-based control during the N-2 contingency. A BESS operating strategy is proposed that would enhance the transactive rationing mechanism. The necessary enabling changes to communication systems, controls and utility tariffs are discussed, along with some ancillary benefits.

transactive energy, power distribution, energy sto↗

Case Study: Healthcare Realty's Medical Office Solar PV

This case study describes how Healthcare Realty partnered with a renewable energy advisor to establish its solar program and make progress towards its energy and GHG emissions reduction goals; all of the projects in the pipeline will be financed through third-party ownership, via power purchase agreements or through a feed-in-tariff program.

solar, solar PV, photovoltaic, onsite solar, healt↗

Electric Vehicle Efficiency Ratios for Light-Duty Vehicles Registered in the United States

Electric vehicles (EVs) use energy more efficiently than gasoline vehicles. This is one of their primary attributes, enabling other benefits such as improved torque and reduced operating costs and greenhouse gas emissions. An electric vehicle efficiency ratio (EVER) is therefore important when calculating the financial and environmental benefits of EVs, calculating the impact that EVs have on a manufacturer's Corporate Average Fuel Economy rating, calculating credits in trading schemes such as California's Low Carbon Fuel Standard, fuel price leveling, designing electricity tariffs from utility-owned public charging infrastructure, creating EV alternatives to gasoline excise taxes, and more.

33 ADVANCED PROPULSION SYSTEMS↗