Advanced Development and Testing of the SunRing Heliostat

The Department of Energy’s Solar Energy Technology Office has set a 2030 cost target of 5 ¢/kWh for Concentrated Solar Power (CSP) plants. The solar field represents the largest cost in a CSP tower plant (30-40% of total installed cost) with commercial heliostats having installed costs of approximately $140/m2 . Solar Dynamics (SD) proposes to develop and test an advanced version of our SunRing™ heliostat that reduces its total installed and proves its bankability for commercial installations. The advanced SunRing heliostat will have an installed cost 40% lower than current commercial heliostats. Phase 1 of the project developed an advanced azimuth drive system that achieved cost savings, reduced operational loads, and improved robustness compared to the baseline design. The advanced drive concept was validated with a full-scale prototype which has seen 1.6 years of simulated lifetime. Periodic wear measurements and positional accuracy tests have affirmed the design. In Phase 2 the SunRing heliostat is transitioned to a Technology Readiness Level of 6-7. This is accomplished with a series of lifecycle tests on the advanced drive system where the drive will be subject to extreme environmental conditions. Drive testing will yield a final, commercially viable design that will be integrated into a full-scale SunRing heliostat. This commercial-intent SunRing will be put through a suite of optical performance tests which will be independently validated by the National Renewable Energy Laboratory. The focus of Phase 2 is to de-risk the technology and provide comfort in the SunRing’s ability to perform in commercial solar projects. This is critical to gain the investment needed to deploy the SunRing at commercial scale. Our team is well suited to propose this project. SD has built and deployed the baseline SunRing heliostat. In addition, SD personnel have led development, design, and operations of some of the largest CSP power plants in the world.