Energy Systems Integration Newsletter: March 2021

In this edition, NREL helps Los Angeles create a pathway to 100% renewables, celebrates research and leadership staff for Women's History Month, takes major strides in improving grid stability, and more!

Pioneering NREL Analysis Empowers Los Angeles in Its Pursuit of 100% Renewables

In 2017, the Los Angeles Department of Water and Power sought out NREL to lead analysis of how its power system could evolve to a 100% renewable future, jumpstarting LA100: the Los Angeles 100% Renewable Energy Study.

Over the past 3 years, a multidisciplinary team of dozens of NREL experts ran more than 100 million simulations and studied a range of future scenarios—an analytical undertaking of unprecedented scale and complexity. NREL found reliable, 100% renewable energy by 2045—or even 2035—is achievable with rapid deployment of wind, solar, and storage technologies this decade. The analysis revealed that while achieving a reliable, 100% clean energy future is a significant undertaking with substantial investments, there are multiple pathways to get there—and LA can get started now.

Read more about the findings from this pioneering study that paves the way for other jurisdictions to reach their own clean energy goals, equitably and economically.

Women's History Month: Celebrating NREL Research Pioneers and Leaders

In honor of Women's History Month, we recognize NREL research and leadership staff who are advancing NREL's mission to transform energy. Take a look back at some of the NREL team we have profiled, whose work covers a variety of specialties, including energy security and resilience, grid modernization, high-performance computing, and technological collaboration with state, local, and tribal governments.

Sheila Hayter: Laying the Foundation for an Interconnected Energy Future

Fatima Al Suwaidi: Visiting UAE Engineer Details How NREL and Masdar Are Helping Shape Her Career Goals

Kristen Ardani: From Research to Rooftops

Annabelle Pratt: Managing Energy at All Scales

Jennifer Daw: Working at the Crossroads of Energy, Water, and Land

Elizabeth Doris: Connecting NREL with the World It Serves

Sherry Stout: Building Capacity and Collaboration for Energy Resilience

Julieta Giraldez-Miner: Providing Innovative Integration Options to Utilities and Power Systems

Andrea Watson: Building Teams To Solve Energy Challenges Globally

Eliza Hotchkiss: Refining Resilience in Energy Systems

Fei Ding: Helping Power System Industries Do the Real Work of Grid Resilience and Reliability

Sakshi Mishra: Addressing the Challenges of Climate Change and Advocating for Women in STEM

Charisa Powell: Developing Tools and an Emulation Platform To Safeguard Distributed Energy Resource Systems

Kristin Munch: Advancing Computing Capabilities to Efficiently Simulate, Analyze Complex Energy Systems

NREL Clears Hurdle to Dynamic Stability for Renewables

As wind and solar energy become larger players on the bulk grid, their complex electronic behavior adds new challenges around bulk grid stability. Two NREL resources are available to understand such large-scale stability: one, a hardware testbed that rigorously evaluates at-scale interconnections, and the other, a Python toolkit to perform simulated bulk-grid stability analysis. These resources are now being applied in multiple communities around the world to identify grid stability weaknesses and opportunities.  

Read the full story.

Juan Torres Speaks at Congressional Hearing on Grid Resilience

This month, NREL's associate laboratory director of Energy Systems Integration, Juan Torres, testified alongside other grid experts at a congressional hearing on Lessons Learned from the Texas Blackouts: Research Needs for a Secure and Resilient Grid.

In the hearing—called by the U.S. House of Representatives Committee on Science, Space, and Technology—Torres presented his perspective on the changing state of the power grid and impacts on energy security and resilience. He then responded to questions from congressional attendees on actions—current and prospective—to strengthen the energy grid. The 3-hour session took place on March 18 and offered spirited conversation around energy resilience, not only for Texas but also from a national perspective.

Torres' written testimony  describes U.S. Department of Energy and NREL progress in energy resilience and next steps. A video recording of the hearing is also available. Shortly after Torres' testimony, another NREL research leader was invited to a different grid-related congressional hearing. The laboratory program manager for Buildings Research, Roderick Jackson, testified a week after Torres on Building Technologies Research for a Sustainable Future. Jackson's testimony is available online.

Research Platform Offers New Insights into Fast-Charging Station Cybersecurity

With the demand for electric vehicles accelerating across the country, fast-charging infrastructure is expanding to meet consumer needs. In response to this massive expansion, researchers at NREL are leading the way in understanding the impact of these systems on the power grid while minimizing vulnerabilities to cyberattacks. Using NREL's Cyber-Energy Emulation Platform, researchers can analyze real and virtual network traffic in normal and cyberattack scenarios.

Learn more about how NREL is using the Cyber-Energy Emulation Platform to secure fast-charging infrastructure.

Two New Papers Highlight the Impacts of High Levels of Inverter-Based Resources on Power Grids

As many island power systems seek to integrate high levels of renewable energy, they face new challenges on top of the existing difficulties of operating an isolated grid. With their drastically declining cost, variable renewables, such as wind and photovoltaics (PV), are increasingly being integrated into island grids to reduce the use of imported fuels. NREL researchers Andy Hoke, Vahan Gevorgian, Shahil Shah, Przemek Koralewicz, Wallace Kenyon, and Ben Kroposki recently published Island Power Systems with High Levels of Inverter-Based Resources: Stability and Reliability Challenges. This paper examines how to ensure the frequency and voltage stability in an island power system with very high instantaneous levels of wind and PV and focuses on reliability and stability challenges on short timescales (microseconds to seconds).

Dynamic stability is a major concern in maintaining the security of power grids as the generation mix transitions to higher levels of inverter-based resources. Researchers at NREL and the Department of Energy published a paper that takes a detailed look at using impedance-based stability analysis to evaluate stability problems involving inverter-based resources. Results were published in Impedance Methods for Analyzing Stability Impacts of Inverter-Based Resources: Stability Analysis Tools for Modern Power Systems. This paper gives an overview of the impedance methods and describes the growing number of applications where they are used for stability analysis, ranging from microgrids and shipboard power systems to wind and PV power plants with high-voltage AC and DC transmission networks.

California Public Utilities Commission Report Highlights Partnership Project between NREL, San Diego Gas and Electric Co.

A partnership project between NREL and the San Diego Gas and Electric Co. exploring advanced metering infrastructure was recently included in the Electric Program Investment Charge (EPIC) program report. EPIC was established by the California Public Utilities Commission to assist the development of non-commercialized new and emerging clean energy technologies in California while aiding commercially viable projects.

In the featured project, NREL and the San Diego Gas and Electric Co. partnered to analyze real-time data collected from smart meters the utility has deployed across the city. This pervasive and continuous data from the grid edge could benefit real-time operations, and this project explores opportunities in the space.

Check out the full EPIC report to learn more about this project.

Q&A with Alexandra Aznar: USAID-NREL Partnership Readies for Expansion under Biden Administration

One of the ways that NREL advances the deployment of renewable energy resources is through its global partnerships. A flagship is NREL's partnership with the U.S. Agency for International Development (USAID), which assists more than 40 countries around the world with policy, planning, and renewable energy deployment support.

The USAID-NREL Partnership provides assistance primarily through its global toolkits, which offer resources, best practices, and assistance through an Ask an Expert service. In December 2020, after working on the USAID project, Alexandra (Alex) Aznar, a program manager in NREL's Integrated Applications Center, took over the USAID-NREL portfolio.

Read our full Q&A with Alex Aznar.

USAID, NREL Enhance Renewable Energy Resource Data Analysis Tool To Inform Decision-Making

USAID and NREL have released an enhanced and expanded version of the Renewable Energy Data Explorer (RE Data Explorer), a publicly available geospatial analysis tool that can inform renewable energy policy, investment, and deployment decisions. With funding from USAID through the USAID-NREL Partnership as well as the Advanced Energy Partnership for Asia, this release includes a redesigned user interface; the addition of high spatial and temporal resolution solar resource data for Southeast Asia; and wind, solar, and complementary data for many countries. Over the coming weeks, renewable energy data sets will be added for the entire world.

Read the full story.

Publications Roundup

Voices of Experience: Microgrids for Resiliency
Energy resilience is becoming an increasing point of focus for utilities, policymakers, regulators, and community leaders. As options are explored to help the grid withstand disruptions caused by everything from natural disasters to cyberattacks, microgrids are a popular emerging solution to mitigate the consequences of outages.

The latest entry in the Voices of Experience series, produced by the Department of Energy's Office of Electricity, examines microgrids and their role in improving energy resilience, focusing on the value that they provide to both utilities and customers. A compendium included with the latest entry specifically looks at microgrid controllers to see how they can be operated to meet different needs.

Optimizing Design and Dispatch of Renewable Energy Systems
A new report from NREL researchers in Applied Energy proposes a novel model to improve system design. This model recommends an optimally sized mix of renewable energy, conventional generation, and energy storage technologies while simultaneously optimizing the corresponding dispatch strategy. To develop the model, researchers looked at a variety of venues, including a small campus and a local hospital, taking into consideration utility rate tariffs, opportunities for the integration of multiple renewable technologies, and incentives for production. The model demonstrated a potential for millions of dollars in savings over 25 years and thousands of kilowatts of installed renewable energy.

Impact of Emergency Diesel Generator Reliability on Microgrids and Building-Tied Systems
With resilience becoming a major concern in the development and improvement of energy systems, microgrids are emerging as an alternative to traditional diesel generators to provide emergency backup power. In this study published in Applied Energy, NREL researchers compare the reliability for backup energy production of diesel generator-based microgrids to that of centralized emergency diesel generators reliant on short-term fuel stockpiles tied to individual buildings. The study determined that traditional diesel generator configurations cannot provide the required reliability to withstand a grid outage for multiple days. The researchers demonstrate that diesel generator-based microgrid configurations have at least a 93% probability of reliably providing backup power for upwards of 2 weeks.

Co-Simulation of Transactive Energy Markets: A Framework for Market Testing and Evaluation
The exponential expansion of integrated distributed energy resources (DERs) presents a challenge for grid operators: how to incorporate all these new assets while providing reliable, affordable, and cost-effective electricity. As traditional centralized grid services increasingly demonstrate an inability to provide the flexibility utilities need to accommodate these DERs, distribution-level transactive energy markets have emerged as a viable solution. This study from NREL researchers published in the International Journal of Electrical Power and Energy Systems establishes a co-simulation framework to help utilities test and evaluate these markets prior to deployment.

Using NREL's HELICS co-simulation platform, the study developed and applied this framework to perform simultaneous evaluation of market performance, DER performance, DER bidding approaches, and distribution feeder power quality in two DER penetration levels. Compared to full retail net energy metering, the study shows that transactional markets provide increased value for a majority of customers while reducing overall costs for the utility.