Session: 04-01: Energy Storage Systems and Applications

Paper Number: 170136

170136 - Optimizing Photovoltaic and Radial Packed Bed Thermal Energy Storage Systems for Cost-Effective and Reliable Heating 

Abstract: 

As the global demand for energy continues to rise, there is an increasing need to develop sustainable and cost-effective energy solutions, particularly for rural and hard-to-reach locations. These areas often face unique challenges, including limited access to traditional energy infrastructure and higher energy costs. Photovoltaic (PV) technology has emerged as a very low-cost solution that can be deployed behind-the-meter independently of existing energy infrastructure and in regions with suboptimal direct normal irradiance (DNI), in contrast to other solar technologies that require high DNI. However, the intermittent nature of solar energy necessitates the integration of energy storage systems to ensure a consistent and reliable energy supply. When heat is the required form of energy, thermal energy storage (TES) systems provide the lowest cost form of energy storage.

In this context, the development of an optimized PV + TES system for heating applications presents a significant opportunity to reduce heating costs and enhance energy security. By leveraging the advantages of both PV and TES technologies, it is possible to create a hybrid system that minimizes reliance on potentially expensive fuels while ensuring a stable and continuous energy supply.

This study focuses on the design and optimization of a PV + radial packed bed TES + Natural Gas (NG) system to deliver alternative heating for a greenhouse in a cold climate. Radial packed bed TES technology is considered due to its simplicity and utilization of natural, low-cost, and abundant storage media.

Through a performance-based techno-economic analysis (TEA), a parametric suite of configurations achieving different levels of heating cost reduction has been determined. The levelized cost of heat (LCOH) of PV + TES + NG systems is shown to be competitive with or lower than NG-only systems, depending on the financing structure. A configuration has been selected from the optimal LCOH set and optimized for an anticipated deployment by the Mi'kmaq tribe in Maine. The ratio of bed height-to-diameter is optimized for its impact on thermocline shape and charge/discharge profiles, ensuring optimal performance and efficiency.

TEA results are under refinement, and thermocline modeling results are being prepared for presentation at this conference.

Presenting Author: Luke McLaughlin Sandia National Laboratories

Presenting Author Biography: Luke received a Ph.D in Mechanical Enginering from the University of Wyoming in 2022. He has since worked as a R&D Mechanical Engineer at Sandia National Laboratories. Luke's areas of research include concentrated solar thermal technologies and thermal energy storage.