ASYMMETRIC TECHNOLOGIES, LLC — Department of Energy SBIR Phase I: C56-15d

Description

Concentrated solar-thermal power (CSP) systems offer several advantages compared to traditional photovoltaic (PV) installations, including inherent storage capabilities (leading to improved grid stability) and the ability to provide non-carbon-based thermal energy to industrial processes. However, CSP installation and operation costs must be reduced to make these systems competitive options. Two of the biggest cost drivers for CSP systems are (1) wire trenching/routing/maintenance for control signals to the individual heliostat components and (2) ongoing calibration of the heliostats due to wind or other environmental effects. Wireless control of the heliostats offers a potential solution for reducing both costs, but the wireless solutions that have been broadly studied (Zigbee and IEEE 802.11 mesh variants) are limited in their ability to scale and provide accurate modeling and simulation tools that are needed to control the costs and risks of a large-scale heliostat deployment. Based on the expertise developed by this team, the design approach makes heavy use of modeling and simulation, custom antenna designs, and beamforming approaches, far beyond anything we have seen in current heliostat communication solutions or literature. The team sees an opportunity to use our expertise in this area to develop Wireless Networks for Solar Uniform Modularity (WiNSUM), a low-cost, flexible, and secure wireless communication capability for CSP systems. Certain variants of these wireless systems also offer the opportunity to provide built-in heliostat alignment and calibration in addition to control data. The team also proposes to develop a comprehensive CSP installation network simulation tool that will allow operators to easily design and test their wireless heliostat networks under a variety of conditions. In the Phase I SBIR, we propose to study and document unique CSP wireless requirements and compare these requirements to the capabilities of two specific wireless standards: IETF 6TiSCH and 802.11ad (60GHz-based). Both wireless standards can be implemented with very low-cost, secure hardware for large-scale networks but differ in data rates, range, and specific network configurations. In addition to the inherent security and anti-jamming characteristics of the 60GHz spectrum, the 802.11ad standard also uses beam-forming antennas, which may offer an opportunity to perform coarse alignment of the heliostats using the wireless modules. In Phase I, the team will also leverage our expertise with open-source simulation tools and antenna design for both wireless standards to begin initial development of a CSP wireless network simulation tool that can provide comprehensive simulation of the wireless network including factors such as mesh formation, antenna radiation patterns, channel hopping, and interference. Long-term outcomes of this work include low-cost, flexible and secure wireless hardware modules, firmware, and software suitable for CSP applications and a high-fidelity network simulation tool that can integrate with other modeling and simulation tools, such as NREL SolarPILOT, and reduce the risks of large scale CSP deployments. Having reviewed prior work aimed at this problem, such as the HelioMesh and AutoR projects, we are confident that we can deliver wireless solutions enabling increased CSP scale.