Skip to main content

Energy Systems Integration Newsletter: September 2019

New prototype brings NREL collaborators together; Q&A with Elizabeth Doris; USAID, NREL launch Resilient Energy Platform

NREL researchers discussing battery testing protocol and design in lab.

Storage Startup Brings Prototype to NREL via the Wells Fargo Innovation Incubator

Trends like continued population growth, vehicle electrification, and greater adoption of renewable generation are changing the magnitude and shape of utility load profiles. Because of this, the demand for grid services such as load shedding and load shifting is expected to increase in coming years.

Increasing energy storage capacity in the built environment is part of a portfolio of solutions for adapting to and staying ahead of these trends. Yotta Solar is an Austin-based startup that is working with NREL to characterize its prototype battery unit under the auspices of the Wells Fargo Innovation Incubator (IN2) program. Their battery unit, named the "SolarLEAF," is a flat white box small enough to fit behind a typical PV panel.

If successful, space-saving technologies like this could enable more utility customers to deploy energy storage on their properties. Over the next several months, a team of NREL researchers from across the lab will use equipment in the Thermal Test Facility to characterize the performance of Yotta's unique thermal management system under a variety of conditions.

"A next-generation battery system is a technology that benefits from a multi-disciplinary approach," says Johney Green, NREL's associate lab director for mechanical and thermal engineering. "Between power systems, buildings, battery characterization, and PV research, we can offer that here. And that's unique."

This recent NREL.gov feature article has more on the Wells Fargo Innovation Incubator program.

Q&A with Elizabeth Doris: Connecting NREL with the World It Serves

Elizabeth Doris is the principal laboratory program manager of the State, Local, and Tribal Program. Her work concerns the intersection of technology and society, a topic that crosscuts departments at NREL. Her experience in the field has led to efficient adoption of breakthrough Energy Systems Integration (ESI) research for governments across the nation.

Learn more about Doris and her work at NREL in this Q&A.

Paper on Surface Albedo Selected as One of Solar Energy Journal's Best Papers

The editors of Solar Energy recently selected their Best Papers published in the Solar Energy journal in the last two years. Among the papers selected was one co-authored by NREL researchers Manajit Sngupta and Yu Xie, titled "Surface Albedo and Reflectance: Review of Definitions, Angular and Spectral Effects, and Intercomparison of Major Data Sources in Support of Advanced Solar Irradiance Modeling over the Americas." The study defines albedo and reflectance in the context of solar applications and examines the main sources of surface albedo data that can be used to help solar irradiance modeling efforts.

The award will be presented by the President of the International Solar Energy Society at the 2019 Solar World Congress in Santiago, Chile, Nov. 4–8.

USAID-NREL Partnership Launches Resilient Energy Platform

The USAID-NREL Partnership launched the Resilient Energy Platform, which provides expertly curated resources, training materials, data, tools, and direct technical assistance in planning resilient, sustainable, and secure power systems. The Resilient Energy Platform enables decision makers to assess power sector vulnerabilities, identify resilience solutions, and make informed decisions to enhance power sector resilience at all scales.

Weaknesses within power sector infrastructure, systems, or operations are susceptible to natural, technological, and human-caused threats. Impacts from these threats include power outages resulting from physical infrastructure damage, fuel supply shortages, shifts in energy demand, and financial and economic implications associated with such events. The platform helps countries address these vulnerabilities by providing strategic resources and direct country support to enable planning and deployment of resilient energy systems.

In a recent webinar, Sherry Stout, a leading power sector resilience expert at NREL, provides an overview of the platform as well as its supplemental Power Sector Resilience Planning Guidebook. The webinar also details how the Lao People's Democratic Republic used the Resilient Energy Platform to develop a resilience action plan with the support of NREL and USAID's Clean Power Asia program.

Learn more about how the USAID-NREL Partnership is delivering clean, reliable, and affordable power in the developing world by visiting its website.

Sheila Hayter Defines Platform in Year as ASHRAE President

For Sheila Hayter, recent president of the American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE), her presidential platform, "Building Our New Energy Future," is all about interconnectivity.

"We are moving to a point where there is not going to be a separation of the problem at the meter," said Hayter. "You can't think about things going on at the building side as different from what's happening at the grid side."

Hayter notes a discrepancy in perspectives and awareness of the issue between grid and power-focused researchers on one side, and real-world practitioners and building operators on the other. Some 70% of our energy is consumed by buildings, and further electrification, including the advent of electric vehicle charging within buildings, will further increase that proportion of use. On the other side, those involved in building design and operation are still tackling the challenge of achieving zero-energy buildings, let alone the idea of a seamless back-and-forth of energy supply between buildings and the power grid. Hayter believes that the key to addressing this discrepancy is by connecting with the people.

"You can't change the direction of a ship very fast, but you can get people continuing the conversation," said Hayter.

To emphasize this message, Hayter focused on engaging ASHRAE members on an individual and local level. She visited 67 different chapters and sections, more than any other previous ASHRAE president. She met with student branches at 25 different universities and visited 23 U.S. states, four Canadian provinces, and 16 countries across five continents.

Read this NREL.gov feature article for more on Hayter's work as president of ASHRAE.

NREL, Anterix Announce Completion of First Phase of Private LTE Network Project

As part of a partnership with Anterix (formerly pdvWireless), researchers at NREL have successfully demonstrated increased reliability for distributed generation systems, such as solar and wind, using LTE communications. The results show potential for private LTE networks to effectively transmit control information without interruption or delay, regardless of usage level or other congestion conditions.

"Adding more renewables and advanced energy technologies to the grid requires a backbone of secure, reliable communications," said Juan Torres, associate director for Energy Systems Integration at NREL. "NREL's work with Anterix at the ESIF is answering questions and identifying scalable solutions to allow communications to keep pace with deployment."

The partnership between NREL and Anterix has focused on analyzing the performance of LTE broadband networks and accelerating the development and validation of innovative approaches to enhance the resilience of distribution systems, including microgrids, with high penetration of distributed energy resources. The initial results show that Anterix's private 900-MHz broadband spectrum can enable a private LTE network to quickly communicate signals to energy grid devices.

"These initial results give a baseline for controlling intermittent energy sources that utilities can refer to as they plan for a future filled with solar generation," said Mike Brozek, senior vice president of technology for Anterix.

The project now moves into phase two, in which the network will be expanded to include a full suite of utility grid automation devices and the advanced distribution management system control system. Wireless congestion scenarios will be tested with high impact communications, such as control systems, prioritized over normal traffic such as meter reads. These efforts will be guided by an independent industrial advisory board to ensure the testing scenarios reflect real world utility conditions.

New Grid Modernization Laboratory Consortium Report Details Role of Renewables in Stabilizing Energy Systems

A new report published through DOE's Grid Modernization Laboratory Consortium summarizes an extensive body of work pertaining to the nitty-gritty of grid control: How can wind power, alongside a few short-term storage technologies, improve the reliability of power systems? The research cataloged in this report covers three years of full-scale demonstrations of active power control using grid assets coordinated between institutions in a real-time "super laboratory."

The range of assets and the controllable grid interface allowed NREL to bring testing to a new level of detail, for example, the potential to understand operation and maintenance costs of shifting a turbine's load to provide grid services. The Flatirons Campus testing arrangement consisted of the controllable grid interface providing controllable power signals to assets and recording their response. With this setup, NREL effectively simulated a full wind farm by aggregating the response of its turbine across wind conditions.

The assets, including a 1-MW battery system, a 1-MW solar array, multimegawatt wind turbines, and a controllable grid interface, were also integrated into a sort of hybrid renewable plant, allowing the researchers to survey and test the reliability services offered by the collective devices. This work contains entirely unique insights into how a new suite of utility assets can support the grid—it is the first report to comprehensively unite large-scale renewable energy technologies and test their varied control features. 

New Professional Master's Program Prepares Students To Energize the World

The new Professional Master's Program in Next-Generation Power and Energy Systems offered by the University of Colorado Boulder Department of Electrical, Computer, and Energy Engineering in partnership with NREL prepares students to build the electric power grid of the future. Instructors from CU Boulder's faculty and NREL research programs teach courses designed to help students learn about grid modernization-related challenges the lab is addressing, such as renewable energy integration, cybersecurity, and the potential of autonomous energy grids.

"NREL researchers and CU faculty together bring real-world scenarios to students who can leverage Colorado's hub for renewable energy development," said Ben Kroposki, director of the Power Systems Engineering Center at NREL.

Applications are due Dec. 1, 2019, for classes starting fall semester 2020, when CU Boulder's new program begins.

Summer Intern Makes an Impact at NREL

Every summer, interns are invited to NREL to advance in their studies, support NREL research, and present what they've learned. Several interns lent their expertise to energy systems integration research throughout summer 2019, including Pooja Gupta, a third-year doctorate student from Arizona State University. Gupta was a standout student and support researcher. As stated by her project lead, Himanshu Jain, Gupta is a "quick learner, asks tough and relevant questions, and was willing to question assumptions we made throughout the project." The following is a short interview with Gupta about her time at NREL.

How did you find out about this internship?

One of my faculty advisors at Arizona State University actually forwarded the internship to all the students and encouraged them to apply. He forwarded to all the students in the department. That's how I got to know about this position. I then applied and was interviewed. I was also motivated to apply after seeing all of the positive experiences my friend at ASU had. He interned with NREL last summer and again this summer.

What did you work on while at NREL?

I was focused on finding the reliability of the power systems when you have many renewables integrated in the system; this particular project was implemented for a utility. My other project was finding the shortcomings of existing tools we have for simulating the dynamics of power systems—that was kind of a use-case study of whether we can proceed with the existing tools, or if we need to come up with more tools.

Did you get to choose the project you worked on? How does that work?

When I started working, I was asked "Is there a sort of project that you're interested to work on?" I think that was really cool—the first project I didn't have a clue, but the second I was given some choice.

How would you describe the experience overall?

It was very rewarding. The internships at NREL are worth anyone's time. Three months feel like a very short time to work on two projects—you start something, and then you do not want to leave without fulfilling your objectives. The work culture is great at NREL; everyone is supportive and friendly.

New Pubs in ESI: Advanced Grid Control and a New Cyber Defense Framework

Real-Time Feedback-Based Optimization of Distribution Grids: A Unified Approach
This paper continues the authors' pursuit of a framework for real-time control and optimization of distributed energy resources. Their most recent progress, published in IEEE Transactions on Control of Network Systems, includes an algorithmic method for optimizing distributed energy resources at both an individual, and aggregated level. Their method was validated on real distribution system data, is robust against inaccuracies in distribution system modeling, and doesn't require pervasive metering of resources. The authors' work is a step closer toward autonomous energy grids, capable of self-regulating the millions of new grid devices coming online.

A Multidimensional Holistic Framework for the Security of Distributed Energy and Control Systems
Energy systems depend increasingly on extensive communication networks, which could expand the grid's vulnerabilities. This paper, published in IEEE Systems Journal, presents a cybersecurity framework that uses advanced technologies and intelligent algorithms to improve the defenses for a changing industry. The framework is modeled within a utility's enterprise and multiple substations network, and can be used to enhance the security and resilience of microgrid control systems. The results of the evaluation are used to recommend best business practices, and ultimately introduce a new approach to cybersecurity that blends contextual data analysis and machine learning to respond to advanced persistent threats.

Quantifying the Opportunity Limits of Automatic Residential Electric Load Shaping
In future energy markets, consumers and utilities could shape their loads around economic and environmental benefits. This paper, published in Energies, considers load-shaping behavior in the context of forecasted electricity prices, which would add elasticity to the marketplace and would support continuous load-shaping. The authors compared techniques for quantifying residential appliance behavior, and studied the opportunities for single-family homes in the Northwest United States to instantaneously add or reduce load. The authors present their data and code and discuss future studies to estimate the benefits of continuous automatic residential load shaping.