Cycle 16 NCESR Projects Show Progress

NCESR Principal Investigators for Cycle 16
NCESR Principal Investigators for Cycle 16

We applaud the eight NCESR Cycle 16 projects for focusing on improving renewable and/or sustainable energy. The following Cycle 16 project research updates are from the beginning of their funding, which started on January 1, 2022, into the second year of the project, which will end on December 31, 2023. NCESR provides funding for new two-year seed projects each year through the collaboration with Nebraska Public Power District (NPPD). Research updates for Cycle 17 projects that started January 1, 2023, will be provided in future newsletters. Cycle 18 pre-proposals will begin the review process in June 2023.

Robust Topologically Protected Energy-Efficient On-Chip Microlaser for Secure Data Center Communication Systems

PI: Dr. Wei Bao, Associate Professor
UNL Electrical and Computer Engineering

CO-PI: Dr. Christos Argyropoulos, Associate Professor
UNL Electrical and Computer Engineering

The laser has penetrated our society pervasively since its inception in 1960. High-quality lasers with exceptional properties, such as low threshold, high efficiency, high output power, high speed, small size, and single-mode operation, have, therefore, become essential for many critical applications. Our project developed a novel photonic crystal microlaser with the smallest footprint in the world and small energy consumption. Ideal for future data center applications. The project is close to the finish of all the objectives in the proposal.

Diamond-Coated Metallic Structures for Molten-Salt Thermal-Energy Storage Systems
Relates to NPPD Low-Carbon Initiative

PI: Dr. Bai Cui, R. Vernon McBroom Associate Professor
UNL Mechanical and Materials Engineering

CO-PI: Dr. Yongfeng Lu, Lott Distinguished University Professor
UNL Electrical and Computer Engineering

This project aims to develop a low-cost, large-area deposition method for diamond coatings on metallic structures to address critical corrosion issues in molten-salt thermal-energy storage (MSTES) systems for solar thermal power stations. The research team has successfully developed a novel laser-assisted chemical vapor deposition process for manufacturing of protective diamond coatings on stainless steel surfaces in open air.

This process will extend the lifetime and reliability of MSTES systems and thus reduce the maintenance and replacement costs. This new technology will allow for more solar energy (thermal plants instead of photovoltaic, PV) and/or nuclear (0 carbon dioxide production) generating sources.

Next-Generation Laser-Driven Lightsources and Imaging Modalities for Nondestructive Evaluation (NDE) of the Energy Infrastructure

PI: Dr. Matthias Fuchs, Associate Professor
UNL Physics and Astronomy

CO-PI: Dr. Bradley Shadwick, Professor
UNL Physics and Astronomy

The goal of the project is the development and application of novel compact light sources that can generate radiation ranging from terahertz to X-ray wavelengths and imaging modalities for non-destructive evaluation of the energy infrastructure.

To this end, we have performed experiments that demonstrate a novel method of efficiently generating high brightness X-ray radiation from a table-top setup with a beam quality that is comparable to that of kilometer-scale conventional synchrotron facilities. We have used this source for high-resolution X-ray imaging. We have also used X-ray radiation generated by a conventional source to perform advanced X-ray tomographic imaging with micrometer resolution that is sensitive to density variations in the sample and can greatly increase the visibility of inhomogeneities in low absorption objects or voids. Finally, we have developed a source of quantum-entangled photons at visible wavelengths that will be used for an advanced imaging modality termed “ghost imaging.”

Harnessing Domain Formation in Ferroelectric Oxides for Weather- and Environment-Resilient Energy Applications

PI: Dr. Xia Hong, Associate Professor
UNL Physics and Astronomy

CO-PI: Dr. Xiaoshan Xu, Associate Professor
UNL Physics and Astronomy

CO-PI: Dr. Takashi Komesu, Research Associate Professor
UNL Physics and Astronomy

Xia Hong, Xiaoshan Xu, and Takashi Komesu have worked on an NCESR project aiming at understanding and controlling the ferroelectric domain properties in ferroelectric oxide thin films and free-standing membranes, which can facilitate their implementations in weather- and environment-resilient energy applications. By combining advanced epitaxial thin film growth with structural, electrical, spectroscopic and scanning probe microscopy studies, the team has achieved high quality samples of Pb(Zr,Ti)O3 and hexagonal R(Fe,Mn)O3 and investigated the critical roles of electrode screening and interfacial bonding condition on the polarization switching dynamics and domain wall roughness.

This award has supported the research activities of six graduate students and two undergraduate students. To date, the research has resulted in two journal publications and two submitted papers.

Flexible Secondary-Life Battery for Grid Energy Storage

PI: Dr. Wei Qiao, Professor
UNL Electrical and Computer Engineering

CO-PI: Dr. Liyan Qu, Associate Professor
UNL Electrical and Computer Engineering

The goal of this project is to explore and prove an innovative concept for a flexible secondary-life battery (FSLB) system with hot-swappable, modular battery packs retired from electric vehicles for grid energy storage. The FSLB system is tolerant to failure of one or multiple battery packs, can self-balance the state of charge (SOC) of different battery packs during operation, has lower repurposing, system and maintenance costs, and is scalable to different voltage/power levels.

The project team has designed a 10-kW single-phase modular power converter for a proof-of-concept study of the FSLB, developed a basic intelligent battery energy management system (iBEMS) for online condition monitoring, fault tolerant control and SOC balancing of the FSLB system, carried out computer simulations to validate the FSLB system designed and the iBEMS, and conducted a scalability study for the FSLB concept for grid-scale energy storage applications.

The FSLB provides a disruptive solution to grid-scale energy storage with 25-50% expected cost reduction and significantly improved flexibility, modularity, reliability and maintainability over the state-of-the-art battery storage systems using new or secondary-life battery cells.

A novel Framework for Cybersecurity Vulnerability Analysis of Energy Sector OT Communications Technologies

PI: Dr. Hamid Sharif, Charles J. Vranek Professor
UNL Electrical and Computer Engineering

CO-PI: Dr. Michael Hempel, Research Assistant Professor
UNL Electrical and Computer Engineering

CO-PI: Dr. Kenneth L. Hansen, Associate Vice Chancellor Facilities Management and Planning
UNMC Environmental, Agricultural and Occupational Health

We are rapidly progressing through our research tasks on the NCESR project. We have completed several components of our framework, including the formal modeling and verification processes, as well as strategies for using it to identify problem areas and vulnerabilities within protocols and their implementation. We also established an OT device testing platform that allows us to explore and verify these findings, and we are currently working on establishing the framework’s computer simulation capabilities. This framework will be utilized for exploring various OT protocols prevalent in energy grid installations, using information from UNMC’s power infrastructure as a case study environment.

Our findings have been published in several peer-reviewed conference papers and journal publications, and we are currently working on more papers focused on our latest efforts and their findings.

Finally, we continue our grant proposal development based on our work for NCESR and NPPD, including a collaborative proposal with ORNL for DOE, and another proposal for NSF, to enable us to continue this effort beyond the seed funding stage.

Ultra-Efficient Power Module for MVDC Solid-State Circuit Breakers

PI: Dr. Jun Wang, Assistant Professor
UNL Electrical and Computer Engineering

CO-PI: Dr. Liyan Qu, Associate Professor
UNL Electrical and Computer Engineering

Medium-voltage direct current (MVDC) distribution systems are an emerging solution to integrate renewable and electrified energy sources and loads with high efficiency, high density, and high performance. In these systems, DC solid-stage circuit breakers (SSCBs) act as vital protection devices to promptly isolate faulty subsystems without the need for arc extinction but are subject to low-efficiency challenges. This project addresses the SSCB’s efficiency and bulky cooling system problems by proposing the development of a bidirectional SiC FET module (ηPak) optimized for MVDC SSCBs, capable of achieving efficiency > 99.988%. This can be attained by adopting the proposed: 1) back-to-back press-pack of enormous-scale SiC FET dies; 2) fault-tolerant designs; and 3) multiphysics optimization.

The project targets the delivery of one 1.7 kV, 167 A, 600 μΩ, ηPak submodule. At this point, a basic four-die sample has been fabricated and validated by four-wire resistance tests and shear strength tests. In the meanwhile, a monolithic spring is innovated to replace the conventional disc springs with much improved electrical and thermal conductance. Out of our first year's work, we have filed one non-provisional patent and two invention disclosures, published one conference paper (accepted) and submitted two more conference digests.

Protein Fibers from Sorghum Distillers Grains for Value-Additions to Sorghum-Based Biofuel Industry

PI: Dr. Yiqi Yang, Professor
UNL Textiles, Merchandising & Fashion Design

CO-PI: Dr. Bingnan Mu, Research Scientist
UNL Textiles, Merchandising & Fashion Design

We are working on the development of protein fibers from sorghum distillers grains (sorghum DG) for value-additions to the sorghum biofuel industry. Low values of sorghum distillers grains substantially decrease the profitability of sorghum-based biofuel industry. Sorghum distillers grains are mainly used as livestock feed for less than $100/ton because of their poor digestibility and potential health risk to animals imputable to dense sulfur crosslinkages in sorghum proteins. Sorghum proteins are better than other plant proteins for biobased products because their high molecular weights, dense crosslinkages and rich hydrophobic amino acids ensure the toughness and water stability of the final products. We have developed an aqueous spinning system suitable for both kafirin and glutelin from sorghum distillers grains.

We have found that glutelin substantially improved the spinnability of protein solution and, thus, the mechanical properties of wet-spun sorghum protein fibers. The final diameters of fibers were 13 µm, finer than average wool fibers, indicating a desirable processability of fiber spinning. The mechanical properties of sorghum-protein-derived fibers met the minimal requirement for textile applications. We continue to optimize the spinning conditions, including fiber oxidation and washing, to improve the toughness and durability of sorghum protein fibers.

Meanwhile, we will develop various reinforcements suitable for sorghum proteins to further improve the wet properties of the fibers. Sorghum protein fibers developed from our technology have lower processing costs. The material and energy costs using our technology are less than $1.2 for production of 1 kg of protein fibers, while the price of 1 kg of protein fibers is at least $6.5/kg. Converting 1 ton of sorghum DG into fibers could add values of at least $1,300, more than 10 times of the price of sorghum DG.