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Ethyl alcohol (ethanol) is known to possess a pair of closely-spaced excited torsional substates (gauche +, gauche -) at an energy of approximately 57 K above the ground (trans) torsional substrate. We report an extended analysis of some gauch- - gauch+ Q branch (delta J=0) transitions witha three-substrate fixed frame axis method (FFAM) Hamilton.
Disordered proteins frequently serve as interaction hubs involving a constrained variety of partners. Complexes with different partners frequently exhibit distinct binding modes, involving regions that remain disordered in the bound state. While the conformational properties of disordered proteins are well-characterized in their free states, less is known about the molecular mechanisms by which specificity can be achieved not with one but with multiple partners. Using the energy landscape theory concept of protein frustration, we demonstrate that complexes of disordered proteins exhibit a high degree of local frustration, especially at the binding interface. These suboptimal interactions lead to the possibility of multiple bound substates, each displaying distinct frustration patterns, which are differently populated in complexes with different partners. These results explain how specificity of disordered proteins can be achieved without a single common bound conformation and how the conflict between different interactions can be used to control the binding to multiple partners.
Electric utilities have a main responsibility to protect the lives and safety of their workers when they are working on low-, medium-, and high-voltage power lines and distribution circuits. With the anticipated widespread deployment of smart grids, a secure and highly reliable means of maintaining isolation of customer-owned distributed generation (DG) from the affected distribution circuits during maintenance is necessary to provide a fully de-energized work area, ensure utility personnel safety, and prevent hazards that can lead to accidents such as accidental electrocution from unanticipated power sources. Some circuits are serviced while energized (live line work) while others are de-energized for maintenance. For servicing de-energized circuits and equipment, lock-out tag-out (LOTO) programs provide a verifiable procedure for ensuring that circuit breakers are locked in the off state and tagged to indicate that status to operational personnel so that the lines will be checked for voltage to verify they are de-energized. The de-energized area is isolated from any energized sources, which traditionally are the substations. This procedure works well when all power sources and their interconnections are known armed with this knowledge, utility personnel can determine the appropriate circuits to de-energize for isolating the target line or equipment. However, with customer-owned DG tied into the grid, the risk of inadvertently reenergizing a circuit increases because circuit connections may not be adequately documented and are not under the direct control of the local utility. Thus, the active device may not be properly de-energized or isolated from the work area. Further, a remote means of de-energizing and locking out energized devices provides an opportunity for greatly reduced safety risk to utility personnel compared to manual operations. In this paper, we present a remotely controllable LOTO system that allows individual workers to determine the configuration and status of electrical system circuits and permit them to lock out customer-owned DG devices for safety purposes using a highly secure and ultra-reliable radio signal. The system consists of: (1) individual personal lockout devices, (2) lockout communications and logic module at circuit breakers, which are located at all DG devices, and (3) a database and configuration control process located at the utility operations center. The lockout system is a close permissive, i.e., loss of control power or communications will cause the circuit breaker to open. Once the DG device is tripped open, a visual means will provide confirmation of a loss of voltage and current that verifies the disconnected status of the DG. Further the utility personnel will be able to place their own lock electronically on the system to ensure a lockout functionally. The proposed LOTO system provides enhanced worker safety and protection against unintended energized lines when DG is present. The main approaches and challenges encountered through designing the proposed region-wide LOTO system are discussed in this paper. These approaches include: (1) evaluating the reliability of the proposed approach under N-modular redundancy with voter/spares configurations and (2) conducting a system level risk assessment study using the failure modes and effects analysis (FMEA) technique to identify and rank failure modes by probability of occurrence, probability of detection, and severity of consequences. This ranking allows a cost benefits analysis to be conducted such that dollars and efforts will be applied to the failures that provide greatest incremental gains in system capability (resilience, survivability, security, reliability, availability, etc.) per dollar spent whether capital, operations, or investment. Several simulation scenarios and their results are presented to demonstrate the viability of these approaches.
Compromises attributable to the Advanced Persistent Threat (APT) highlight the necessity for constant vigilance. The APT provides a new perspective on security metrics (e.g., statistics based cyber security) and quantitative risk assessments. We consider design principals and models/tools that provide high assurance for energy delivery systems (EDS) operations regardless of the state of compromise. Cryptographic keys must be securely exchanged, then held and protected on either end of a communications link. This is challenging for a utility with numerous substations that must secure the intelligent electronic devices (IEDs) that may comprise complex control system of systems. For example, distribution and management of keys among the millions of intelligent meters within the Advanced Metering Infrastructure (AMI) is being implemented as part of the National Smart Grid initiative. Without a means for a secure cryptographic key management system (CKMS) no cryptographic solution can be widely deployed to protect the EDS infrastructure from cyber-attack. We consider 1) how security modeling is applied to key management and cyber security concerns on a continuous basis from design through operation, 2) how trusted models and key management architectures greatly impact failure scenarios, and 3) how hardware-enabled trust is a critical element to detecting, surviving, and recovering from attack.
Dear Secretary Moniz: I am pleased to present the financial statements and operating data for Southwestern Power Administration (Southwestern) for Fiscal Year (FY) 2012. In FY 2012, Southwestern delivered over 4.1 billion kilowatt-hours of energy to its wholesale customers in Arkansas, Kansas, Louisiana, Missouri, Oklahoma, and Texas, generating $195 million in revenue. In fulfilling its mission to market and reliably deliver renewable Federal hydroelectric power, Southwestern maintains 1,380 miles of high-voltage transmission lines, substations, and communications sites, contributing to the reliability of the regional and National electric grid. Southwestern also actively partners with the Department of Energy, the U.S. Army Corps of Engineers, Southwestern’s customers, and other Federal power stakeholders to most effectively balance their diverse interests with Southwestern’s mission while continuing to maximize Federal assets to repay the Federal investment in the 24 hydropower facilities within Southwestern’s marketing region. Southwestern is proud of its past successes, and we look forward to continuing to serve the Nation’s energy needs in the future. Sincerely, Christopher M. Turner Administrator
Dear Secretary Chu: I am pleased to present the financial statements and operating data for Southwestern Power Administration (Southwestern) for Fiscal Year (FY) 2011. In FY 2011, Southwestern delivered over 4.1 billion kilowatt-hours of energy to its wholesale customers in Arkansas, Kansas, Louisiana, Missouri, Oklahoma, and Texas, generating $167 million in revenue. In fulfilling its mission to market and reliably deliver renewable Federal hydroelectric power, Southwestern maintains 1,380 miles of high-voltage transmission lines, substations, and communications sites, contributing to the reliability of the regional and National electric grid. Southwestern also actively partners with the Department of Energy, the U.S. Army Corps of Engineers, Southwestern’s customers, and other Federal power stakeholders to most effectively balance their diverse interests with Southwestern’s mission while continuing to maximize Federal assets to repay the Federal investment in the 24 hydropower facilities within Southwestern’s marketing region. Southwestern is proud of its past successes, and we look forward to continuing to serve the Nation’s energy needs in the future. Sincerely, Christopher M. Turner Administrator
Dear Secretary Chu: I am pleased to present the financial statements and operating data for Southwestern Power Administration (Southwestern) for Fiscal Year (FY) 2010. In FY 2010, Southwestern delivered nearly 7.6 billion kilowatt-hours of energy to its wholesale customers in Arkansas, Kansas, Louisiana, Missouri, Texas, and Oklahoma, generating $189 million in revenue. In fulfilling its mission to market and reliably deliver renewable Federal hydroelectric power, Southwestern maintains 1,380 miles of high-voltage transmission lines, substations, and communications sites, contributing to the reliability of the regional and National electric grid. Southwestern also actively partners with the Department of Energy, the U.S. Army Corps of Engineers, Southwestern’s customers, and other Federal power stakeholders to most effectively balance their diverse interests with Southwestern’s mission while continuing to maximize Federal assets to repay the Federal investment in the 24 hydropower facilities within Southwestern’s marketing region. Southwestern is proud of its past successes, and we look forward to continuing to serve the Nation’s energy needs in the future. Sincerely, Christopher M. Turner Administrator
A method of modeling electric supply and demand with a data processor in combination with a recordable medium, and for estimating spatial distribution of electric power outages and affected populations. A geographic area is divided into cells to form a matrix. Within the matrix, supply cells are identified as containing electric substations and demand cells are identified as including electricity customers. Demand cells of the matrix are associated with the supply cells as a function of the capacity of each of the supply cells and the proximity and/or electricity demand of each of the demand cells. The method includes estimating a power outage by applying disaster event prediction information to the matrix, and estimating power restoration using the supply and demand cell information of the matrix and standardized and historical restoration information.
This report provides details on the activities and accomplishments of Phase 1 of the Sunshine State Solar Grid Initiative (SUNGRIN) Project for the period beginning 4/28/2010 and ending 12/31/2011. SUNGRIN is a five-phase high-penetration solar PV project within the Systems Integration (SI) area of the Solar Energy Technologies (SETP) Program, under the SunShot Initiative. SUNGRIN is focused on understanding and enabling high-penetration grid-connected solar PV through simulation assisted studies of actual Florida utility high-penetration distribution circuits as well as substations and, to a limited extent, the bulk power system. Each phase builds and expands upon the efforts of the previous phase, leading to a comprehensive examination and understanding of high-penetration solar PV issues, from the solar resource to the conversion and integration technologies to the electric power system, with Florida and it’s utility partners providing the broad range of conditions and system integration scenarios necessary to develop useful insight and solutions. This phase, Phase 1, was funded with American Recovery and Reinvestment Act (ARRA) funds. This version of the final report is organized to align with statement of project objectives (SOPO) critical milestones.
Protective barriers for protecting assets (e.g., electrical power transformers and other substation components). The protective barrier may include a lower portion and an upper portion. The lower portion may include first and second laterally spaced A-frame structures having a first protective member assembly extending between aligned legs of the respective A-frame structures on one side thereof. The first protective member assembly may include a first plurality of substantially horizontally extending protective members oriented at an angle relative to a horizontal plane. The first and second A-frame structures may have a second protective member assembly extending between aligned legs of the respective A-frame structures on an opposing side thereof. The upper portion may comprise a third protective member assembly. Methods of making a protective barrier are also disclosed.
As distributed energy resources (DER) achieve higher penetration levels in distribution systems, the normal flow of power (and fault current) is no longer unidirectional, from substation source to load (or fault). The increased importance of DER has also led to pending revisions in the DER interconnection standards, particularly voltage regulation and ride-through, with publication of a new IEEE Standard 1547 expected in early 2018. These changes have complicated normal distribution system operation, and they will also complicate distribution system protection. The U. S. Department of Energy undertook a review of protection state-of-the-art for this new environment in order to identify gaps and propose near-term solutions.
This paper presents a data-driven load modeling methodology for distribution system quasi-static time-series (QSTS) simulation considering both diversity and variability characteristics of distribution loads. Based on our previous work in [1]-[2], a variability library and diversity library have been established based on the realistic high-resolution data collected from actual utility feeders. Given the load profile for the start-of-circuit load of a feeder, the loads on the feeder nodes can be modeled with both diversity and variability instead of being directly scaled from the substation load profile according to the distribution allocation factors. With diversified load models, the load-induced impact on the feeder operation characteristics, such as voltage ramp and regulator operations, can be better considered in QSTS simulation. The proposed modeling methodology has been tested on both the IEEE 123-bus feeder and an actual utility feeder model, and the simulation results have demonstrated the merits of deploying the proposed load modeling methodology.
Maintaining electrical generation assets to meet peak demand increases the cost of providing electricity to a country’s buildings and insufficient assets can result in power outages. In order to keep reliable electricity costs low for consumers and demand charges low for utilities, there exist markets and financial incentives for limiting consumption during peak demand.The team has partnered with an electrical distributor servicing a 1,390 km2 area and 178,368 buildings with the aim of using urban-scale building energy modelling to inform business decisions necessary for the operation of their electric grid. A suite of software has been developed that allows the scalable creation of a “digital twin” for all buildings in the utility’s service area. This virtual utility area is analysed for targeted deployment of new technologies or policies to assess building-specific savings, effects on critically-loaded grid infrastructure (e.g. feeders, substations), and aggregated impact to utility-scale operations.This work leverages 15-minute data from each building to compare actual and simulated monthly peak-hour demand and assessment of the load factor for each building. Findings include market characterization via clustering of relative energy use profiles for ~180,000 buildings as well as simulation-informed savings opportunities indicating residential load factors of 0.17, commercial load factors of 0.2-0.4 depending on year of construction, and general load factors of 0.16-0.5 depending on building type.
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.
The explosion of new ideas for distributed energy resources and advanced distribution grid algorithms faces a critical challenge: how can one effectively develop and evaluate these breakthrough technologies without an adequate set of power systems network, load, and resource data to test against? Today's open test systems, particularly for distribution systems, are tiny and incomplete; and though with enough effort, obtaining utility data under NDA can overcome scale challenges, the results can't be openly shared, preventing fair comparison. The Smart-DS project-led by NREL in partnership with MIT, Universidad Pontificia Comillas, CYME, and EDD-is working to overcome this gap by generating multiple large-scale, open, synthetic, distribution systems that are realistic but not real. These datasets go beyond a single medium voltage feeder (~1000 customers) to cover entire metropolitan areas and their surrounds with up to hundreds of feeders and millions of customers, complete with low voltage customer connections and high voltage sub-transmission. This scale allows adequate testing and analysis of not just local controls and advanced DERs, but also multiple substation interactions, optimized switching, full-scale distribution-OPF, and more. To accompany these datasets, the project is also building a rich set of scenario generation tools that can be used for distribution and transmission systems alike. This includes automated, spatially aware access to world-class, high-resolution solar, wind, and weather data: forward looking generation mixes: and highly configurable DER, load, climate, outage, control-scheme, and other scenarios. We will also highlight DiTTo, an exciting open-source, multi-way distribution dataset transformation tool for many-to-many format translation with scenario, merge/split, and many other manipulation capabilities.
As decarbonization goals drive increasing levels of renewable generation, there is a need to understand the time- and location-based savings benefits of demand-side management (DSM) programs. The challenges of the 'duck curve' are driving the utility industry to consider how programs can be optimized to match demand profiles with low carbon generation resources. From an infrastructure standpoint, time- and location-targeted DSM could serve as a ‘non-wires alternative’ (NWA) to defer equipment upgrades. Additional DSM value streams are motivating innovation in savings evaluation, providing more resolved insights beyond the total annual program impact. Methods grounded in the principles of billing analysis, leveraging hourly metering at the distribution grid, can provide new visibility into the spatial and temporal savings achieved through DSM. A large body of work has investigated related topics including interval meter-based savings analysis, the time- varying nature of efficiency measures, and NWA. A less studied topic concerns the impact of DSM on the grid, based on metered consumption. This paper presents an analysis of interval data across more than 25,000 customers and twelve substations, from the Sacramento Municipal Utility District. The results show for different locations on the grid: achieved savings and the impact on grid consumption; hourly savings shapes for DSM program participants and non-participants, and how those shapes vary with season; and the impact of the programs on peak demand. These findings show the current impact of DSM, with implications for future, more intentional targeting as the utility continues to pursue aggressive electrification, efficiency, load flexibility, and reliable NWA.
Power distribution systems are more prone to disruptions and cause most power system outages. We propose a service restoration technique to recover the system service (electricity delivery) following an extreme event-triggered substation outage. The proposed technique considers the problem of controlling distributed energy resources (DERs) of a distribution system with the objective of achieving maximum load pick up while satisfying network flow and voltage constraints. The problem is formulated as a model predictive control (MPC), where a linearized optimal power flow (OPF) model is employed to describe the network. The formulation is augmented with a ramping (up) reserve product for the DERs to ensure an upward monotonic load restoration as time evolves. We perform simulations considering the IEEE 13-bus test feeder integrated with wind, solar, microturbine, and energy storage devices. We demonstrate the efficacy of the devised technique in restoring the system loads monotonically, without shedding previously restored loads. We also show the benefit of co-optimization of power and reserve products for DERs on service restoration. In addition, the capability of the technique in regulating nodal voltages and reducing renewable power curtailment is demonstrated.
With the influx of distributed generation (DG) penetration, power utilities have adopted active anti-islanding protection methods to prevent an unintentional islanding condition. One commonly used protection scheme is implemented through the use of a transfer trip from the upline connected substation to the DG facility and is required when the capacity of connected DGs exceed a certain threshold of local minimum load. The threshold established by standard IEEE 1547.2-2009 states that a 3:1 minimum load to generation ratio is acceptable to ensure the DG will not sustain an unintentional island. However, the term “minimum load” is not precisely defined in any standard, and in practice, a light load value is chosen by engineers through manual methods that can be inconsistent, not representative and change drastically based on various cases. To solve this problem, this paper proposes a new light load calculation method creating consistency and better accuracy; the method has been implemented in. NET C# application and is used within Dominion Energy.