Sandia National Laboratories,
Keywords: decarbonization, process heat, concentrating solar, solar thermoochemistry
Summary:Greenhouse gas (GHG) emissions from industrial processes account for nearly a quarter of all GHG emissions in the United States, which totaled approximately 6 billion metric tons of CO2 equivalent in 2020. Cement and steel production contribute to ~14% of global anthropogenic CO2 emissions due to the use of fossil fuels for high-temperature heating requirements and chemical reactions that release CO2, such as the calcination of calcium carbonate to make Portland cement. Other industrial processes that produce greenhouse gas emissions include food processing and drying, chemical and materials synthesis, and petroleum refining. Nearly three-quarters of the energy used in industrial processes is for heat, and 90% of that heat is currently generated using fossil fuels. In concentrating solar technologies (CST), a large array of mirrors is used to concentrate sunlight onto a receiver, typically to heat a fluid or media to high temperatures that can be used immediately to generate heat for power production and process heat or can be stored and used later (even when the sun is not shining). In concentrating solar power (CSP) applications, the heat is used to heat steam (or another working fluid) to spin a turbine/generator for utility-scale electricity. The use of these CST configurations can be used to generate high-temperature process heat for industrial applications. Recent research and studies demonstrate the feasibility of using CSP to produce high-temperature process heat (~300˚C – 1000˚C) for industrial applications such as cement and steel manufacture, chemical syntheses (e.g., ammonia), and production hydrogen and solar fuels. Through continued advancements in materials, components, and systems integration, CSP technology can be used together with other renewable and carbon-free energy technologies to bring industry closer to decarbonization. In this talk, a brief overview of CST will be introduced. The potential uses and challenges of CST to decarbonize industrial processes will be presented, and several examples of R&D projects programs will be given, with an emphasis on work performed at the National Solar Thermal Test Facility (NSTTF) at Sandia National Laboratories. The NSTTF is a one-of-a-kind facility in the US for the research and development of CST. These examples include solar-thermal hydrogen production, green ammonia synthesis, and thermal energy storage. The indispensable benefits of technoeconomic and systems analyses and collaborations with industrial partners to progress the field will also be discussed.