Resources

 

 

2023 HelioCon Annual Workshop

The Heliostat Consortium for Concentrating Solar-Thermal Power (HelioCon) hosted its annual workshop during the ASME-ES Conference July 10-12 in Washington D.C. During the summary session portion of the workshop, the HelioCon team provided technical work highlights, introduced recently awarded RFP projects, and led a discussion on progress made on gaps identified in the heliostat roadmap report as well as future goals. During technical sessions, researchers presented information about specific HelioCon topic areas and initiatives. 

Publications

HelioCon Annual Report 2023

December 5, 2023
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Authors: Guangdong Zhu, Chad Augustine, Tucker Farrell, Devon Kesseli, Parthiv Kurup, Rebecca Mitchell, Matthew Muller, Daniel Tsvankin, Shashank Yellapantula, Alexander Zolan, Kenneth Armijo, Randy Brost, Margaret Gordon, Daniel Small, Jeremy Sment, Braden Smith, Mike Collins, Joe Coventry, John Pye, Ye Wang, Michael Cholette, Giovanni Picotti, Maziar Arjomandi, and Matthew Emes

Abstract

The HelioCon Annual Report 2023 provides detailed information on progress the HelioCon team has made since its founding, including expanding the number of partnerships with industry, research, education, and other institutions; increasing staff size; providing information to a growing audience through its web presence; and participating in national and international conferences with industry leaders. In 2023, HelioCon successfully completed its key milestones and further defined goals and objectives for 2024. HelioCon will continue to advance U.S. heliostat technology, capabilities, and the national workforce by:

  • Carrying out high-impact R&D and technology validation projects at national labs for strategic core capabilities and infrastructure.
  • Engaging relevant industries and research institutes to advance heliostat technologies and minimize commercial deployment risks through new round of RFP. 
  •  Expanding workforce through student internships and collaboration with universities and community colleges.
  • Enhancing the impact of HelioCon activities such as participating researchers, students, publications, seminars, and R&D projects.  

We look forward to engaging with industry and academia through direct partnerships, workshops, conferences, meetings, and other in-person/virtual opportunities in the upcoming years.

Compilation of a Solar Mirror Materials Database and an Analysis of Natural and Accelerated Mirror Exposure and Degradation

October 4, 2023
Subject: https://doi.org/10.1115/1.4063079

Authors: Tucker Farrell, Yue Cao, Frank Burkholder, Daniel Celvi, Christa Schreiber, Guangdong Zhu

Abstract

The National Renewable Energy Laboratory (NREL) has been conducting exposure experiments on solar reflectors for over four decades. Thousands of mirror samples from over 100 suppliers have been exposed to and monitored in a range of relevant environments. These test conditions include outdoor test settings and several controlled laboratory environments. These samples have been rigorously individually characterized using a series of reflectance measurements, visual inspections and, in some cases, in-depth composition analysis to identify degradation modes, reflectance losses, and other mirror properties integral to understanding the solar reflector’s life cycle. This article compiles the decades of measurement data into a concise statistical analysis. It includes exposure and degradation data for numerous reflector types, including secondary-surface reflector permutations of polymer and glass superstrates with silver and aluminum reflectors as well as front-surface reflectors. The results herein are intended to analyze environmental stressors and degradation trends among various historical and state-of-the-art solar reflectors. This article may be used to support solar reflector design, effective testing methodology, and inform manufacturing decisions moving forward. Presented are the results of the compiled database and an initial analysis for degradation rate modeling using full-spectrum and wavelength-dependent approaches. The database is a growing resource hosted on a live, publicly accessible website. In conjunction with the analysis presented here, the database provides a valuable resource to the solar reflector manufacturing and testing industry.

HelioCon: A roadmap for advanced heliostat technologies for concentrating solar power

September 2023
Subject: https://doi.org/10.1016/j.solener.2023.111917

Authors: Guangdong Zhu , Chad Augustine , Rebecca Mitchell , Matthew Muller , Parthiv Kurup , Alexander Zolan , Shashank Yellapantula , Randy Brost , Kenneth Armijo , Jeremy Sment , Rebecca Schaller , Margaret Gordon , Mike Collins , Joe Coventry , John Pye , Michael Cholette , Giovanni Picotti , Maziar Arjomandi , Matthew Emes , Daniel Potter , Michael Rae

Abstract

Heliostat-based concentrating solar-thermal power (CSP) systems can offer immense potential to provide low-cost, dispatchable renewable thermal and electrical energy to help achieve 100% decarbonized energy infrastructure in the United States. Heliostats are a major determinant of both capital cost and performance of state-of-the-art commercial molten salt towers and Generation 3 CSP systems. In 2021, the U.S. Department of Energy (DOE) Solar Energy Technologies Office (SETO) launched the Heliostat Consortium (HelioCon), a five-year initiative to advance heliostat technologies. The HelioCon mission is threefold: (1) establish strategic core testing and modeling capabilities and infrastructure at national labs; (2) support heliostat technology development in relevant industries; and (3) serve as a central repository to integrate industry, academia, and other stakeholders for heliostat technology research, development, validation, and deployment. In this Perspective, HelioCon presents a roadmapping study on advancing heliostat technologies, intended as a central reference for the entire CSP community.

Initial Heliostat Supply Chain Analysis

November 2022
Subject: Publication Released: NREL/TP-7A40-83569

Authors: Parthiv Kurup, Sertac Akar, Chad Augustine, David Feldman

Abstract

Globally, the growing demand for concentrating solar power (CSP) technologies, primarily for electricity generation plants has been met with supply chains primarily composed of plentiful commodity materials such as steel, aluminum, and glass. Often the majority of the commodity materials are sourced within the domestic market where generating plants are constructed. Although specialty components are required for CSP solar field components - including mirror panels used for heliostat applications - these specialty components constitute about 30-50% of total system installed costs. Only a few companies and countries, including the United States, have developed the capacity to supply such specialty components. This report is an initial assessment of the global and U.S. heliostat supply chain.

Roadmap to Advance Heliostat Technologies for Concentrating Solar-Thermal Power

October 2022
Download Roadmap Report

Authors:
Guangdong Zhu, Chad Augustine, Rebecca Mitchell, Matthew Muller, Parthiv Kurup, Alexander Zolan, Shashank Yellapantula, Randy Brost, Kenneth Armijo, Jeremy Sment, Rebecca Schaller, Margaret Gordon, Mike Collins, Joe Coventry, John Pye, Michael Cholette, Giovanni Picotti, Maziar Arjomandi, Matthew Emes, Daniel Potter, and Michael Rae

Abstract

Heliostat-based concentrating solar-thermal power (CSP) systems can offer immense potential to provide low-cost, dispatchable renewable thermal and electrical energy to help achieve 100% decarbonized energy infrastructure in the United States. Heliostats are a major capital cost technology and a performance-dominating component of state-of-the-art commercial molten salt towers and Generation 3 CSP systems. In 2021, the U.S. Department of Energy (DOE) Solar Energy Technologies Office (SETO) launched the Heliostat Consortium (HelioCon), a five-year initiative to advance heliostat technologies.

The HelioCon mission is threefold:
  • (1) establish strategic core testing and modeling capabilities and infrastructure at national labs;
  • (2) support heliostat technology development in relevant industries; and
  • (3) serve as a central repository to integrate industry, academia, and other stakeholders for heliostat technology research, development, validation, and deployment. In this report, HelioCon presents a roadmapping study on advancing heliostat technologies, intended as a central reference for the whole CSP community.

A feasibility study on the application of mesh grids for heliostat wind load reduction

May 2022
Subject: Solar Energy, 240, 121-130.

Authors: Emes, M.J., Jafari, A., and Arjomandi, M.

Abstract

This study examines the effectiveness of mesh grids in heliostat field perimeter fences and edge-mounted devices for heliostat wind load reduction. Two experimental studies were conducted: (1) the effect of mesh porosity and non-dimensional longitudinal distance of a perimeter fence upstream on the forces on a heliostat, and (2) the effect of mesh porosity and non-dimensional height-chord ratio of a heliostat edge-mounted mesh device on the heliostat loads. The experiments were conducted using an instrumented heliostat model positioned in the atmospheric test section of the Adelaide Wind Tunnel. It was found that perimeter mesh fences reduce peak loads by up to 50% and edge-mounted porous mesh devices reduce peak loads by up to 30% at the expense of increasing loads at different elevation angles. The porosity and height-chord ratio of an edge-mounted mesh were found to be important parameters influencing the maximum drag and lift reductions in operating and stow positions. The results of this work show the potential of mesh grids for reducing wind load on heliostats, and the importance of conducting a detailed techno-economic analysis on mesh grids throughout a heliostat field. The application of mesh grids on commercial-scale heliostats requires a further evaluation of the reduction of heliostat wind loads and thus cost of a field through mitigation of the incoming ABL turbulence and wake-induced turbulence from upstream heliostats.

Introduction to Heliostats Document

March, 2022
Download the Report

Authors: Mackenzie Dennis

Abstract

Concentrating solar power (CSP) is naturally incorporated with thermal energy storage, providing readily dispatchable electricity and the potential to contribute significantly to grid penetration of highpercentage renewable energy sources. This overview will focus on the central receiver, or “power tower” concentrating solar power plant design, in which a field of mirrors - heliostats, track the sun throughout the day and year to reflect solar energy to a receiver that absorbs solar radiation as thermal energy. The high-temperature thermal energy can be directly stored with a low-cost heat transfer media, such as molten salt or particles, and, when needed, transfer into electricity through a thermodynamic power cycle. The heliostat represents an integral part of a power tower plant, responsible for collecting and focusing solar energy so that it can efficiently reach the receiver. Heliostat design types and concerns, components, field implementation and performance assessment are summarized along with the standard solar power tower plant design, as a reference to the audience who is interested in heliostats and CSP tower technology.

SolarPaces 2022 Conference Materials

Title Authors Documents
NREL-Led Heliostat Consortium for Research, Development, and Validation (HelioCon) Guangdong Zhu; M. Gordon File
Agile Deflectometry Randy Brost, Braden Smith, Felicia Brimigion File
Gap Analysis of Heliostat Field Deployment Processes Jeremy Sment; Alex Zolan; Mark Speir Slides
HelioCon RFP Information HelioCon team Slides
Heliostat Consortium: Heliostat Soiling Michael E. Cholette Slides
Heliostat Consortium Roadmap: Advanced Manufacturing Gap Analysis Randy C. Brost Slides
Question-Based Gap Analysis of Heliostat Optical Metrology Methods Randy C. Brost Slides
Technical Gap Analysis of Heliostat Components & Controls Kenneth M. Armijo; Matthew Muller; Dimitri Madden; Daniel Tsvankin Slides
Summary of an Initial Heliostat Supply Chain Analysis Parthiv Kurup Slides
Equivalent Breakeven Installed Cost: A Tradeoff-informed Measure for Technoeconomic Analysis of Candidate Heliostat Improvements Alex Zolan; Chad Augustine; Ken Armijo Slides
Heliostat Consortium (HelioCon) Gap Analysis on Wind Load for Achieving a Fully Competitive Heliostat Industry Matthew Emes; Shashank Yellapantula; Jeremy Sment; Kenneth Armijo; Matthew Muller;Mark Mehos; Randy Brost; Maziar Arjomandi Slides
A Non-Intrusive Optical (NIO) Method Measure Optical Errors of in-situ Heliostats in Utility-Scale Power Tower Plants: Detecting Uncertainties in Heliostat Geometry Rebecca A. Mitchell; Tucker Farrell; Devon Kesseli; Guangdong Zhu File