HELIO-NET: Heliostats Empowered with Wireless Integrated Access and Backhaul Technology

The transition from wired to wireless communication in Solar Tower Power Plant (STTP) facilities is critical to reduce installation, infrastructure, and operational expenses. In this paper, the HELIO-NET model is introduced that enables the wireless heliostats to communicate with the central station in the field in a wireless manner following the principles of the Integrated Access and Backhaul (IAB) technology. Initially, the channel modeling is performed within the STTP, following the guidelines of the 3rd Generation Partnership Project (3GPP), and the corresponding data transmission rates for both access and backhaul links are derived, as well as the heliostats' experienced energy efficiency. A two-stage optimization problem of the wireless heliostats' and the photovoltaic or PV-operating access points', i.e., IAB nodes', energy efficiency is formulated and solved in order to determine the IAB nodes' and the heliostats' optimal uplink transmission power levels, as well as the optimal bandwidth splitting in the access and backhaul communication links. Extensive simulations validate the proposed framework, showcasing significant energy efficiency improvements for both the heliostats and PV-operating access points in the National Solar Thermal Test Facility at the Sandia National Laboratories.