Central receiver power towers are regarded as a proven concentrating solar power (CSP) technology for generating utility-scale electricity. In central receiver systems, improper alignment (canting and focusing) of heliostat facets results in beam spillage at the receiver and leads to significant degradation in performance. As a result, proper alignment of heliostats is critical for increasing plant efficiency. Past tools used for analyzing and correcting heliostat alignment at the National Solar Thermal Test Facility (NSTTF) have proven to be laborious and inaccurate, sometimes taking up to six hours per heliostat. In light of these drawbacks, Sandia National Labs (SNL) and New Mexico Tech (NMT) have created the Heliostat Focusing and Canting Enhancement Technique (H-FACET). H-FACET uses a high-resolution digital camera to observe the image of a stationary target reflected by a heliostat facet. By comparing this image to a theoretical image generated via a custom software package, technicians can efficiently identify and correct undesirable deviations in facet orientation and shape. Previous tests have only proven the viability of H-FACET for canting heliostats. As a result, SNL and NMT have expanded H-FACET’s capabilities and analyzed the system’s ability to simultaneously cant and focus heliostats. Initial H-FACET focusing test results have shown improved beam sizes and shapes for single facets. Furthermore, simulations of these tests revealed an approximated system accuracy of better than 1.80 milliradians. This accuracy accounted for technician, position, and additional error sources, suggesting that H-FACET was capable of focusing facets to an even greater accuracy than those seen in the initial tests. When implemented for simultaneous canting and focusing of heliostats, H-FACET has demonstrated its capability to increase peak flux and decrease beam size. These full alignment test results demonstrated an average total system accuracy of 1.17 milliradians on five heliostats. As before, this accuracy included multiple error sources which cannot be corrected by H-FACET. Additionally, these tests revealed that H-FACET can align heliostats in about 1 hour and 30 minutes. Finally, two heliostats aligned with H-FACET maintained average accuracies 1.46 and 1.24 milliradians over a four hour window centered about solar noon. This implies that H-FACET is capable of aligning heliostats to a true off-axis alignment over NSTTF’s operating window. In light of these results, SNL has implemented both the focusing and canting portions of H-FACET at the NSTTF.
Skip Nav Destination
ASME 2012 6th International Conference on Energy Sustainability collocated with the ASME 2012 10th International Conference on Fuel Cell Science, Engineering and Technology
July 23–26, 2012
San Diego, California, USA
Conference Sponsors:
- Advanced Energy Systems Division
- Solar Energy Division
ISBN:
978-0-7918-4481-6
PROCEEDINGS PAPER
Development and Analysis of the Heliostat Focusing and Canting Enhancement Technique for Full Heliostat Alignments
Julius Yellowhair
Julius Yellowhair
Sandia National Laboratories, Albuquerque, NM
Search for other works by this author on:
Kyle Chavez
New Mexico Tech, Socorro, NM
Evan Sproul
New Mexico Tech, Socorro, NM
Julius Yellowhair
Sandia National Laboratories, Albuquerque, NM
Paper No:
ES2012-91039, pp. 237-246; 10 pages
Published Online:
July 23, 2013
Citation
Chavez, K, Sproul, E, & Yellowhair, J. "Development and Analysis of the Heliostat Focusing and Canting Enhancement Technique for Full Heliostat Alignments." Proceedings of the ASME 2012 6th International Conference on Energy Sustainability collocated with the ASME 2012 10th International Conference on Fuel Cell Science, Engineering and Technology. ASME 2012 6th International Conference on Energy Sustainability, Parts A and B. San Diego, California, USA. July 23–26, 2012. pp. 237-246. ASME. https://doi.org/10.1115/ES2012-91039
Download citation file:
20
Views
Related Proceedings Papers
Related Articles
Demonstrating solarpilot’s Python Application Programmable Interface Through Heliostat Optimal Aimpoint Strategy Use Case
J. Sol. Energy Eng (June,2022)
Thermocline Bed Properties for Deformation Analysis
J. Sol. Energy Eng (November,2014)
Experimental Measurements Using Digital Image Correlation Methods: Brief Background and Perspective on Future Developments
J. Eng. Mater. Technol (January,2023)
Related Chapters
Solution of Phased-Mission Benchmark Problem Using the SimPRA Dynamic PRA Methdology (PSAM-0345)
Proceedings of the Eighth International Conference on Probabilistic Safety Assessment & Management (PSAM)
Efficient Transmission Images with QAM Modulation over an AWGN Channel
International Conference on Computer and Electrical Engineering 4th (ICCEE 2011)
A Novel Approach for LFC and AVR of an Autonomous Power Generating System
International Conference on Mechanical Engineering and Technology (ICMET-London 2011)