Student research opportunities

Investigation of optical and structural aspects of sandwich-panel mirror facet design for heliostats.

Project Code: CECS_1037

This project is available at the following levels:
PhD
Please note that this project is only for higher degree (postgraduate) applicants.

Keywords:

Solar thermal, CSP, heliostat, mirror

Supervisor:

Dr Joe Coventry

Outline:

The research proposed in this PhD project relates to optical and structural design of sandwich-panel mirror facets for heliostats, and the nexus between optical and structural design.

The Solar Thermal Group (STG) at the ANU is leading a project to develop a new, low-cost heliostat that could be manufactured, installed and operational at a cost of $120/m2 or lower, as part of the broader ASTRI program to reduce the LCOE of CSP technology to 12 c/kWh by 2020. Within this project, the ANU is developing new mirror facet technologies based on sandwich panels. Many opportunities to improve the state-of-the-art have been identified, to minimise material use and achieve a lightweight structure, and to implement low cost fabrication methods while maintaining high durability. Furthermore, there is the opportunity to enhance solar field performance through tailoring the shape of individual mirror facets, and by using high accuracy manufacturing methods. ANU is also participating in a heliostat field optimisation project (led by CSIRO within ASTRI), which aims to improve the annual optical efficiency of a heliostat field by examining the influence of factors such as heliostat size and aspect ratio, heliostat optical characteristics, tracking method, placement and number of heliostats and towers, and tower height.

Possible research areas may incorporate:

• Heliostat ‘field level’ performance benefits of improved mirror panel optics (e.g. through minimising error in shape, canting, pointing accuracy, tuned facet curvature, thermal stability, etc). Assessment of the impact of manufacturing variability with respect to facet slope error and geometry. Analysis tools may include open-source ray-tracing techniques being developed within ASTRI.
  
• Development of new mirror facet concepts, including investigation of: alternative materials, e.g. for reflective elements (glass/film), skin material (steel, composites), core materials (EPS, honeycomb structures) ; lamination techniques (e.g. thermal bonding, foaming, adhesives); and methods of tailoring shape (e.g. tuning facet curvature on both principal axes, designs with inherent temperature stability).
  
• Structural/optical modelling of sandwich panel mirror facet concepts throughout the manufacturing process, including assembly on the heliostat and during operation in the field. Modelling techniques will include Finite Element Analysis of laminate structures, and will involve developing methods of interfacing between structural and optical analysis tools.

It is expected that the project will include prototyping of new mirror facet concepts, and validation of structural and optical modelling results through extensive testing. STG staff have significant know-how to support the project, through 15 years working with sandwich panel mirrors developed for the ANU’s ‘Big Dish’ and other solar concentrator systems. The STG workshop is equipped with manufacturing facilities for thermally-bonded sandwich panel prototypes, optical characterisation tools and life-time testing methods to support the research. However, the candidate will be encouraged to explore a wide range of alternative mirror panel constructions and manufacturing methods with the potential to meet cost and optical performance goals, and will be supported in developing partnerships with industry. In particular, there is a growing interest from companies within the automotive sector in the manufacture of high-volume heliostat components, including the reflective facets.

Links

International student scholarships
Domestic students

Contact: