Sinter-Resistant Solar Thermochemical Reactive System for High-Temperature Energy Storage and Release

Strontium Carbonate/Strontium Zirconate Combination Enables Efficient, On-Demand Electricity Production

This sinter-resistant reactor system enables efficient and sustainable storage and release of high-quality solar energy, and can operate effectively at temperatures above 1150°C (2102°F). Concentrated solar power (CSP) is a rapidly growing market, with a global value of $10.2 trillion through 2020, and a comparative annual growth rate of 60 percent. However, to reach the Department of Energy’s target cost of $0.05/kWh for solar energy by 2030 – a rate that might allow it to compete with fossil fuels for global energy production – a transformative discovery is necessary. Current solar thermochemical energy storage compounds tolerate moderate amounts of heat (500-1000°C) and are vulnerable to sintering which steadily depletes the compounds available for solar energy storage. The sintering process requires frequent replacement of the expensive storage compounds to maintain efficiency of the solar energy reactor system.

Researchers at the University of Florida have developed a thermochemical energy storage system – strontium carbonate mixed with strontium zirconate – capable of tolerating extreme heat (above 1150°C) without significant loss of efficiency. This system can repeatedly capture and store high-quality solar energy during the day, and rapidly release energy for electricity production during the day and at night.

Application

Sinter-resistant reactor system provides efficient high-temperature storage and on-demand release of solar energy

Advantages

• Resists sintering, allowing repeated exposure to extreme heat without need for frequent reactant renewal
• Reaction does not produce large amounts of alternative chemical compounds, ensuring accessibility to captured solar energy for subsequent power generation
• Release of stored energy is regulated by the presence of solar heat, avoiding the need for expensive catalyst materials to begin electricity production
• Large quantities of thermochemical energy are easily stored in separate locations for on-demand energy production

Technology

This reactor system utilizes solar thermal energy to facilitate endothermic decomposition of strontium carbonate (SrCO3). Resulting chemical compounds are stored separately, and then mixed as needed for on-demand generation of electrical power via a heated fluid and turbine method. The chemical equilibrium is regulated by solar heat, thus eliminating the need for coolant catalysts. The decomposition and exothermic reaction of strontium carbonate does not yield significant side products. Strontium carbonate is highly resistant to sintering through repeated cycles of power generation – this resistance is enhanced by mixture with strontium zirconate (SrZO3) compounds to maintain efficiency of the power generation process.