Session: 06-01: CSP Optical Systems

Paper Number: 156795

156795 - An Analysis of Ground Screws for Heliostat Deployment: Design Proposal to Minimize Environmental Impacts and Reduce Permitting Burden 

Abstract: 

The development and deployment of Concentrating Solar Power (CSP) plants currently face significant challenges. Among these challenges is the complex permitting processes required by the United States’ Environmental Protection Agency’s (EPA’s) National Environmental Policy Act (NEPA). One of the main components of this process is the Environmental Impact Statement (EIS). The Bureau of Land Management (BLM) has established a Solar Programmatic EIS (PEIS) to streamline the approval process for solar projects; however, CSP technologies are currently omitted from this review. Consequently, each CSP project would likely need to undergo a case-by-case review, leading to substantial delays in the development and initialization of CSP power plants. Permitting delays have impeded the growth of CSP as a viable clean energy technology.

To address these challenges, our research focuses on designing heliostat foundation and mounting solutions that align with the Solar PEIS design guidelines that were informed by extensive multi-year cumulative impact studies. By leveraging existing photovoltaic (PV) mounting and deployment technologies, such as ground screws, we aim to create a more efficient and environmentally friendly approach to CSP heliostat field deployment. Our proposed solutions include installation methods along with operations and maintenance procedures, such as the cleaning of heliostats, along with a condensed overview of the policies and regulations governing CSP plant development.

Additionally, we are collaborating with subject matter experts in heliostat deployment and regulatory agencies to enhance the feasibility and pragmaticism of our design(s). We have engaged staff at the BLM and other relevant federal agencies seeking feedback on the degree to which our proposed deployment solutions might be able to leverage prior work in the commercial photovoltaics industry. Having these compliant solutions available for future stakeholders to reference will significantly reduce the time required for the development and overall approval of future CSP power plants. By ensuring similarity to the recommendations in the Solar PEIS and engaging with regulatory bodies and subject matter experts, we aim to reduce the burden of the approval process and promote the future growth of CSP technologies particularly in the newly added regions that were not previously mentioned in the 2012 Western Solar Plan.

To aid the adoptability of heliostats deployed on foundation equipment similar to PV, we are developing a solution matrix that relates ground anchor sizing to heliostat mirror facet area, wind profile, and the specific soil properties. The use of ground screws in our mounting solutions is intended to accelerate the deployment of heliostat fields on rough, uneven terrain with minimal environmental impact to minimize disruption to vulnerable desert ecosystems. Feedback received to reduce overhead costs for future stakeholder engagement with the NEPA approval process for future plants is summarized.

Presenting Author: Kristina Ji Sandia National Laboratories

Presenting Author Biography: Kristina is currently a R&D year-round graduate intern in the concentrating solar technologies group at Sandia National Laboratories pursuing master's degrees in mechanical and computer engineering at the University of New Mexico focusing on space systems and robotics and control systems and computer vision respectively. Kristina's prior work includes supporting automated data collection and analysis for building energy efficiency requirements and reporting with nStone Corp., participant and leadership roles in UNM's Lobo Motorsports' 2023-24 electric vehicle teams and supporting UNM's High Energy Density Physics Lab as a student researcher.