Solar for Industrial Process Heat: A Technical Potential Assessment for the U.S Manufacturing Sector

Renewable energy integration in energy-consuming sectors is essential for addressing global sustainability challenges, notably those linked to air pollution, resource conservation, and climate change. In recent years, despite short periods of stagnant growth, energy-related global carbon dioxide emissions remain at their highest levels, making decarbonization pathways even more urgent and necessary at a large scale. Transitioning to clean energy technologies in the industrial sector is critical since it has the highest energy consumption among the major energy-consuming sectors worldwide. Due to its diversity and complexity, the industrial sector has seen slower technology adoption than other sectors, yet decarbonizing industry remains an essential step toward achieving low-carbon production systems.

In the U.S., the vast majority of energy use in the industrial sector is associated with industrial process heat (IPH). In total, IPH amounts to 8% of U.S. primary energy use and relies predominantly on the combustion of fossil fuels, such as natural gas, coal, and oil, to meet process heat energy demand.

With the emergence of increasingly cost-effective and efficient solar technologies, solar for industrial process heat (SIPH) is gaining renewed attention as an alternative method for industrial heat production. A broad range of solar thermal and electric heating technologies can be used for process heating, and our work provides analyses that assess these technologies to determine the technical and economic potential of SIPH in U.S. manufacturing industries.

This national analysis, which has been conducted by researchers at the National Renewable Energy Laboratory and Northwestern University, specifically evaluates:

• the thermal energy demand of IPH that can be provided by a collection of solar technologies, for all manufacturing industries and regions in the U.S., at an hourly basis; and associated fuel savings
• methods for developing and applying a cost comparison framework for conventional IPH and SIPH systems with industry-relevant metrics, such as levelized cost of heat and payback period
• persisting data gaps in industrial energy usage and barriers to SIPH adoption

The presentation will provide a critical synthesis of our findings, with a focus on the technical potential analysis, where process-level thermodynamic models were integrated with national energy use and technical equipment data to estimate achievable fossil fuel savings. To this end, we developed a model that evaluates thermal energy demand and solar energy supply on a spatial temporal scale, accounting for the effect of variable demand and the addition of thermal energy storage.

We will also discuss identified barriers, both technical and economic, that must be overcome to promote future adoption, and suggest a research agenda for addressing those barriers moving forward.