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Starke, Michael R.

Publications and source records attributed to Starke, Michael R..

11 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2024

Microgrid Controller Survey Report: 2024 Update

In the past decade, the number of microgrids deployed by electric utilities, end-use customers, and third parties has been increasing significantly both in the US and worldwide. The increase is driven by various reasons, such as carbon emission reduction, energy efficiency improvement, reliability and resilience enhancement, energy infrastructure modernization, and more. Microgrid controllers, as the most important components in these deployed microgrids, optimally coordinate the operation and control of the microgrid assets (e.g., distributed energy resources [DERs], energy storage systems, demand response, and even electric vehicles) and ensure that the microgrid is being operated in an efficient, clean, and resilient manner. To that end, the market for microgrid controllers has been growing rapidly in recent years. Various microgrid controllers have been released and continuously updated by vendors to satisfy the different needs of microgrid customers. However, the functionalities demonstrated by microgrid controllers released by different vendors show a huge difference because of a lack of widely known and accepted industrial standards, and various microgrid customers have specific requirements for different applications and scenarios. To obtain a clear view of the current state of the commercial microgrid controllers’ functionalities and identify potential research gaps, a survey of the functionalities of commercial microgrid controllers and the Advanced Distribution Management System (ADMS) developed by vendors and national laboratories was conducted in 2023. The results of the survey are presented in this report with the current status of commercial microgrid controllers analyzed, potential research gaps identified, and future research trends revealed.

24 POWER TRANSMISSION AND DISTRIBUTION↗
DOE OSTI2018

Autonomous Battery Identification and Health Parameterization

Demand for grid energy storage is on the rise as grid resiliency becomes increasingly important. The large number of grid-based applications for energy storage are attractive to utilities, but the cost of large energy storage is often too high. Secondary-use batteries provide an opportunity to significantly lower the cost of a utility-scale energy storage system through the use of repurposed electric vehicle batteries. However, the available batteries from OEMs differ in many key parameters such as chemistry, capacity, and remaining life. Developing a method to autonomously identify these parameters will reduce the time spent installing and commissioning an autonomous multi-chemistry battery energy storage system. In this paper, a chemistry identification technique will be automated and adapted to high capacity, secondary-use batteries to expedite systems integration. Additionally, an approach for integrating these techniques to a utility-scale energy storage system will be discussed.

Starke, Michael R.↗
DOE OSTI2017

Microgrid Optimal Scheduling With Chance-Constrained Islanding Capability

To facilitate the integration of variable renewable generation and improve the resilience of electricity sup-ply in a microgrid, this paper proposes an optimal scheduling strategy for microgrid operation considering constraints of islanding capability. A new concept, probability of successful islanding (PSI), indicating the probability that a microgrid maintains enough spinning reserve (both up and down) to meet local demand and accommodate local renewable generation after instantaneously islanding from the main grid, is developed. The PSI is formulated as mixed-integer linear program using multi-interval approximation taking into account the probability distributions of forecast errors of wind, PV and load. With the goal of minimizing the total operating cost while preserving user specified PSI, a chance-constrained optimization problem is formulated for the optimal scheduling of mirogrids and solved by mixed integer linear programming (MILP). Numerical simulations on a microgrid consisting of a wind turbine, a PV panel, a fuel cell, a micro-turbine, a diesel generator and a battery demonstrate the effectiveness of the proposed scheduling strategy. Lastly, we verify the relationship between PSI and various factors.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
DOE OSTI2016

Networked Microgrids Scoping Study

While the utilization of a microgrid for local power reliability during grid outage and emergencies is a well-known benefit, the integration of microgrids with the broader electrical distribution system will allow for seamless interaction with distribution system operations, contributing to resource and economic optimization, enhanced reliability and resiliency, and improved power quality. By virtue of integration with the distribution system, multiple microgrids should be networked and collectively known as networked microgrids. As a follow-up to the work conducted by Oak Ridge National Laboratory on a microgrid controller [the Complete System-level Efficient and Interoperable Solution for Microgrid Integrated Controls (CSEISMIC)], the main goal of this work is to identify the next steps for bringing microgrid research to the utility industry, particularly as a resource for enhancing efficiency, reliability, and resilience. Various R&D needs for the integration of microgrids into the distribution system have been proposed, including interconnection types, communications, control architectures, quantification of benefits, functional requirements, and various operational issues.

24 POWER TRANSMISSION AND DISTRIBUTION↗
DOE OSTI2016

Chattanooga Electric Power Board Case Study Distribution Automation

In 2009, the U.S. Department of Energy under the American Recovery and Reinvestment Act (ARRA) awarded a grant to the Chattanooga, Tennessee, Electric Power Board (EPB) as part of the Smart Grid Investment Grant Program. The grant had the objective “to accelerate the transformation of the nation’s electric grid by deploying smart grid technologies.” This funding award enabled EPB to expedite the original smart grid implementation schedule from an estimated 10-12 years to 2.5 years. With this funding, EPB invested heavily in distribution automation technologies including installing over 1,200 automated circuit switches and sensors on 171 circuits. For utilities considering a commitment to distribution automation, there are underlying questions such as the following: “What is the value?” and “What are the costs?” This case study attempts to answer these questions. The primary benefit of distribution automation is increased reliability or reduced power outage duration and frequency. Power outages directly impact customer economics by interfering with business functions. In the past, this economic driver has been difficult to effectively evaluate. However, as this case study demonstrates, tools and analysis techniques are now available. In this case study, the impact on customer costs associated with power outages before and after the implementation of distribution automation are compared. Two example evaluations are performed to demonstrate the benefits: 1) a savings baseline for customers under normal operations1 and 2) customer savings for a single severe weather event. Cost calculations for customer power outages are performed using the US Department of Energy (DOE) Interruption Cost Estimate (ICE) calculator2. This tool uses standard metrics associated with outages and the customers to calculate cost impact. The analysis shows that EPB customers have seen significant reliability improvements from the implementation of distribution automation. Under normal operations, the investment in distribution automation has enabled a 43.5% reduction in annual outage minutes since 2012. This has led to an estimated total savings of $26.8 million per year. Examining a single severe weather event3, the distribution automation was able to restore power to 40,579 (nearly 56%) customers within 1–2 seconds and reduce outage minutes by 29.0%. This saved customers an estimated $23.2 million over the course of the storm.

24 POWER TRANSMISSION AND DISTRIBUTION↗
DOE OSTI2016

Microgrid Controller and Advanced Distribution Management System Survey Report

A microgrid controller, which serves as the heart of a microgrid, is responsible for optimally managing the distributed energy resources, energy storage systems, and responsive demand and for ensuring the microgrid is being operated in an efficient, reliable, and resilient way. As the market for microgrids has blossomed in recently years, many vendors have released their own microgrid controllers to meet the various needs of different microgrid clients. However, due to the absence of a recognized standard for such controllers, vendor-supported microgrid controllers have a range of functionalities that are significantly different from each other in many respects. As a result the current state of the industry has been difficult to assess. To remedy this situation the authors conducted a survey of the functions of microgrid controllers developed by vendors and national laboratories. This report presents a clear indication of the state of the microgrid-controller industry based on analysis of the survey results. The results demonstrate that US Department of Energy funded research in microgrid controllers is unique and not competing with that of industry.

24 POWER TRANSMISSION AND DISTRIBUTION↗
DOE OSTI2016

Preliminary Report on Oak Ridge National Laboratory Testing of Drake/ACSS/MA2/E3X

A key to industry acceptance of a new technology is extensive validation in field trials. The Powerline Conductor Accelerated Test facility (PCAT) at Oak Ridge National Laboratory (ORNL) is specifically designed to evaluate the performance and reliability of a new conductor technology under real world conditions. The facility is set up to capture large amounts of data during testing. General Cable used the ORNL PCAT facility to validate the performance of TransPowr with E3X Technology a standard overhead conductor with an inorganic high emissivity, low absorptivity surface coating. Extensive testing has demonstrated a significant improvement in conductor performance across a wide range of operating temperatures, indicating that E3X Technology can provide a reduction in temperature, a reduction in sag, and an increase in ampacity when applied to the surface of any overhead conductor. This report provides initial results of that testing.

24 POWER TRANSMISSION AND DISTRIBUTION↗
DOE OSTI2015

Cost-effective retrofit technology for reducing peak power demand in small and medium commercial buildings

We describe a cost-effective retrofit technology that uses collective control of multiple rooftop air conditioning units to reduce the peak power consumption of small and medium commercial buildings. The proposed control uses a model of the building and air conditioning units to select an operating schedule for the air conditioning units that maintains a temperature set point subject to a constraint on the number of units that may operate simultaneously. A prototype of this new control system was built and deployed in a large gymnasium to coordinate four rooftop air conditioning units. Based on data collected while operating this prototype, we estimate that the cost savings achieved by reducing peak power consumption is sufficient to repay the cost of the prototype within a year.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
DOE OSTI2015

Opportunities for Efficiency Improvements in the U.S. Electricity Transmission and Distribution System

Since 2000, more than 172 quads of electricity have been transmitted on the US transmission and distribution (T&D) grid. Given this significant amount of energy flow, establishing and maintaining an efficient T&D grid is paramount. As shown in the figure below, the total percentage of overall losses in the US electric grid is approximately 6% (5.12% in 2012) (30% lower than the world average since 2000). While these efficiency losses appear to be relatively small from a percentage perspective, the total estimated electricity loss during this time is 10.8 quads.

24 POWER TRANSMISSION AND DISTRIBUTION↗
DOE OSTI2013

Assessment of Industrial Load for Demand Response across U.S. Regions of the Western Interconnect

Demand response (DR) has the ability to both increase power grid reliability and potentially reduce operating system costs. Understanding the role of demand response in grid modeling has been difficult due to complex nature of the load characteristics compared to the modeled generation and the variation in load types. This is particularly true of industrial loads, where hundreds of different industries exist with varying availability for demand response. We present a framework considering industrial loads for the development of availability profiles that can provide more regional understanding and can be inserted into analysis software for further study. The developed framework utilizes a number of different informational resources, algorithms, and real-world measurements to perform a bottom-up approach in the development of a new database with representation of the potential demand response resource in the industrial sector across the U.S. This tool houses statistical values of energy and demand response (DR) potential by industrial plant and geospatially locates the information for aggregation for different territories without proprietary information. This report will discuss this framework and the analyzed quantities of demand response for Western Interconnect (WI) in support of evaluation of the cost production modeling with power grid modeling efforts of demand response.

24 POWER TRANSMISSION AND DISTRIBUTION↗