Internal Ice-on-Coil Thermal Storage

MasterFormat Division 23 71 19.13: Internal Ice-on-Coil Thermal Storage: An In-Depth Look

As energy costs continue to rise and environmental concerns grow, building owners and managers are constantly seeking efficient and sustainable solutions. Thermal energy storage (TES) has emerged as a promising technology, and within this realm, MasterFormat Division 23 71 19.13: Internal Ice-on-Coil Thermal Storage stands out as a particularly innovative approach.

What is Internal Ice-on-Coil Thermal Storage?

Internal ice-on-coil thermal storage is a type of TES system that leverages the high latent heat of fusion of water to store cooling energy. Unlike conventional systems that store chilled water, this method utilizes the phase change of water from liquid to ice and vice versa.

How Does Internal Ice-on-Coil Thermal Storage Work?

The system operates on a simple yet effective principle:

1. Charging (Ice Formation): During off-peak hours, typically at night, when electricity demand and rates are lower, the system uses a refrigerant cycle to chill a heat transfer fluid, often a water-glycol solution.
2. Storage: This chilled fluid circulates through a network of submerged coils within a tank of water. As the fluid absorbs heat from the surrounding water, ice gradually forms on the external surface of the coils, effectively "storing" the cooling energy.
3. Discharging (Ice Melting): During on-peak hours when cooling demand is high, the stored ice melts as warm building water is circulated through the tank. The melting ice absorbs heat from the building water, providing chilled water for air conditioning without the need to run the energy-intensive compressor during peak periods.

Where is Internal Ice-on-Coil Thermal Storage Commonly Used?

Internal ice-on-coil thermal storage systems are particularly well-suited for applications with high cooling loads and predictable usage patterns, including:

• Commercial buildings (offices, hotels, retail spaces)
• Educational institutions
• Healthcare facilities
• Data centers
• Industrial processes requiring chilled water

Installation Best Practices for Internal Ice-on-Coil Thermal Storage Systems

To ensure optimal performance, longevity, and efficiency, consider the following installation best practices:

• Proper Sizing: Accurate load calculations are crucial to determine the appropriate tank size, coil surface area, and system capacity. Undersizing can lead to inadequate ice production, while oversizing results in wasted energy and space.
• Strategic Tank Placement: Locate the storage tank in a readily accessible area for maintenance and inspection. Ensure adequate structural support for the tank's weight, especially when fully charged with ice.
• Insulation: High-quality insulation around the tank is essential to minimize heat loss and maximize energy efficiency. Choose insulation materials with appropriate thermal properties and ensure proper installation to prevent thermal bridging.
• Control System Integration: A sophisticated control system is vital for managing charging and discharging cycles based on real-time energy prices, building occupancy, and other factors. Integrating the system with building automation systems (BAS) optimizes performance and energy savings.

Top Manufacturers of Internal Ice-on-Coil Thermal Storage Systems

Several reputable manufacturers specialize in internal ice-on-coil thermal storage systems. When selecting a manufacturer, consider factors like experience, product quality, warranties, and after-sales support. Some prominent players in the industry include:

• CALMAC
• EVAPCO
• Baltimore Aircoil Company (BAC)
• VIKING Cold Solutions
• Cryogel

Conclusion

Internal ice-on-coil thermal storage is a compelling solution for buildings looking to enhance energy efficiency, reduce operating costs, and lower their environmental impact. By shifting cooling loads to off-peak hours and capitalizing on the natural energy storage capacity of ice, this technology paves the way for a more sustainable and resilient built environment.