Designing Thermal Energy Storage Using Molten Salts for Concentrated Solar HVAC: Engineering Eutectic Molten-Salt Storage Systems, Corrosion-Resistant ... Continuous Solar-Driven Chiller Operations

The transition toward low-carbon buildings and resilient energy infrastructure is forcing the HVAC industry to rethink how cooling energy is generated, stored, and delivered. Cooling demand frequently reaches its highest levels during the daytime, precisely when solar energy is most abundant. Yet conventional solar-assisted cooling systems face a fundamental limitation: solar availability does not necessarily coincide with the complete duration of the building's cooling requirement.

Thermal energy storage provides a powerful solution to this mismatch.

Among the technologies available for large-scale thermal storage, molten salts are particularly attractive for applications requiring elevated operating temperatures, substantial storage capacity, and extended discharge periods. When appropriately selected and engineered, molten-salt systems can capture thermal energy during periods of strong solar production and release that energy later to maintain cooling production when solar input declines.

This book, Designing Thermal Energy Storage Using Molten Salts for Concentrated Solar HVAC, examines this concept from an engineering perspective. Its objective is not simply to describe molten salts as a storage medium, but to explore the complete engineering chain required to transform stored thermal energy into useful and reliable HVAC cooling.

The challenge is multidisciplinary.

A successful system requires careful consideration of salt chemistry, melting characteristics, thermal stability, corrosion, material compatibility, heat-transfer performance, storage-tank design, pumping requirements, freeze protection, instrumentation, controls, and integration with thermally driven chillers. An improvement in one area can introduce penalties elsewhere. Higher operating temperatures may increase storage potential while simultaneously increasing corrosion concerns and material requirements. Larger circulation rates can improve heat transfer but increase parasitic pumping consumption. More storage capacity can extend nighttime operation but increase capital expenditure and thermal losses.

Consequently, thermal energy storage should not be treated as an isolated component. It must be designed as an integrated part of the solar-HVAC system.

The book begins with the fundamentals of molten-salt thermal storage and the role of storage in concentrated solar HVAC applications. It then examines eutectic salt selection and materials engineering before moving into heat-transfer mechanisms, phase-change behavior, circulation, and storage architecture. The later chapters focus on integrating storage with solar collectors and thermally activated chillers, followed by performance optimization, economics, reliability, and long-term operation.

Particular attention is given to practical engineering considerations that can determine whether a theoretical system becomes a reliable operating installation. Corrosion-resistant materials, salt freezing, thermal cycling, heat exchanger performance, insulation, pumping energy, control strategies, and maintenance requirements are therefore treated as fundamental design considerations rather than secondary details.

The ultimate goal is to provide engineers and technical decision-makers with a structured way to evaluate molten-salt thermal storage for solar HVAC applications.

As the built environment becomes increasingly electrified and cooling demand continues to grow, thermal storage can become an important bridge between renewable energy generation and dependable HVAC operation. Concentrated solar thermal systems combined with advanced storage offer an opportunity to move beyond the concept of solar energy being available only when the sun is shining.

The future of sustainable cooling will depend not only on generating clean energy, but also on storing it intelligently and delivering it when it is needed.