Ice Storage Tank Data Center: Latent Thermal Storage For Peak Shifting

An ice storage tank for a data center stores cooling as latent heat in ice, charged off-peak and melted during peak demand, decoupling cooling production from cooling need. Ice storage trades the simplicity of chilled-water sensible storage for far higher energy density and a smaller footprint, at the cost of glycol loops and more complex controls. Center Enamel supplies the bolted, coated, roofed water tanks that scale to campus size for sensible-heat storage and the stainless and FBE tanks and ASME vessels that cover secondary containment for ice or glycol loops, delivered to 100-plus countries. The right choice is matched to the site, not the trend.

Chilled-water sensible storage banks a temperature difference in liquid water - simple, efficient, but large. Ice storage banks latent heat by freezing and melting a medium, delivering more cooling per volume but forcing the refrigeration plant to lower evaporator temperatures and adding glycol and ice-handling complexity. Most data-center campuses have land and value chiller efficiency, so chilled water wins; ice earns its place where footprint is severely constrained and peak demand charges are high.

• Chilled water: simple, efficient, large.
• Ice: dense, small footprint, more complex.
• Ice needs glycol loops and lower chiller temps.
• Chilled water wins on most campuses.

For sensible chilled-water TES, the tank is a large, stratified, coated water store on the chilled side; Center Enamel's bolted GFS and FBE tanks with insulation for chilled duty scale to campus size, and deliveries such as the Italy Sardinia 30,549 m3 process-water tank and Indonesia Cilincing 21,088 m3 build prove that scale. For ice or glycol secondary loops, stainless and FBE bolted tanks and ASME pressure vessels cover the containment and buffer duties. The shell material is matched to the chemistry and code, not a single catalogue option. A caveat applies: the tank is only the thermal store, not the ice maker, glycol loop or controls, and the shell material should be confirmed against the specific chemical and code duty rather than assumed.

• Sensible TES: large stratified coated water tank.
• Bolted GFS or FBE with chilled-duty insulation.
• Ice or glycol: stainless, FBE or ASME vessel.
• Material matched to chemistry and code.

Sizing starts from the actual duty calculation - rainfall capture volume, cooling-makeup balance, greywater generation rate or fire hydraulic demand - not a catalogue number. The coating thickness of 0.25-0.45 mm for GFS or 180-280 micrometres for FBE, the tank lifecycle of 30-50 years, the NSF/ANSI 61 or WRAS potable-contact option and the freeze or tropical duty margin then set the shell, roof and appurtenances. Every figure below is confirmed against the applicable standard and the local authority having jurisdiction.

The figure below is a REAL Center Enamel delivery used here as manufacturing-capability evidence for the tank type discussed, NOT as a claimed data-center, rainwater, greywater, reclaimed, condensate or ice-storage project. Center Enamel's verified project record (case_library.csv) holds no data-center water-reuse, greywater, reclaimed-water, condensate-recovery or ice-storage delivery, so this reference demonstrates the ability to engineer large coated and stainless water tanks for demanding duty, not a claim about this specific application. Where the source did not record a diameter or height, the field reads Not Provided and is never estimated.

Choose on the site, not the trend: if land is available and chiller efficiency is valued, a stratified chilled-water tank wins; if footprint is severely constrained and peak demand charges justify the complexity, ice storage earns its place. Size from the cooling load and the discharge duration you need, confirm the shell material to the chemistry and code, and keep the tank on the chilled side with stratification to separate charge and discharge.

• Chilled water if land and efficiency favor it.
• Ice if footprint and peak charges justify it.
• Size from load and discharge duration.
• Keep tank on chilled side with stratification.

A latent thermal store that freezes water off-peak and melts it during peak demand, decoupling cooling production from cooling need.

Ice banks latent heat and stores far more cooling per volume but needs glycol loops and lower chiller temperatures; chilled water is simpler and more efficient but larger.

Where footprint is severely constrained and high peak demand charges justify the added glycol and control complexity.

Bolted GFS and FBE tanks with chilled-duty insulation for sensible storage, and stainless, FBE or ASME vessels for ice or glycol secondary containment.

A verified single shell of 20,000 m3 was delivered in 2016, establishing the upper bound for one sensible-storage shell.

It can lower energy cost and demand charges and supports free-cooling; the direct PUE effect depends on how the tank is charged.

AWWA D103-09 and ISO 28765 for the bolted structure, with ASME for pressure vessels where the loop requires them.

On the chilled-water side, charged off-peak by chillers and discharged through coils or a plate exchanger during peak, with stratification to keep charge and discharge separate.

From the cooling load and the discharge duration, expressed in refrigeration tons and ton-hours, not a nameplate figure.

Center Enamel supplies the bolted coated shells for sensible storage and the stainless, FBE and ASME containment for ice or glycol loops; the ice maker and controls are integrated by the plant engineer.

About 30 days ex-works for a 1,000-10,000 m3 tank, with on-site bolted erection in weeks versus months for concrete.

Chilled, often humid, duty stresses the lining; documented 0.25-0.45 mm enamel or 180-280 micrometre FBE predicts long-term reliability.

Yes - the lining, not only the steel, should be warranted, because chilled-duty storage stresses the coating over a 30-50 year life.

No - the fire reserve is a separate code-referenced volume and must stay isolated from the TES loop.

Periodic internal inspection of the lining and verification of stratification and appurtenances support a 30-50 year service life.

An ice storage tank for a data center stores latent cooling to shift peak load, trading the simplicity of chilled-water storage for density and a smaller footprint. The choice is matched to the site - chilled water where land and efficiency favor it, ice where footprint and peak charges justify complexity - and the shell material is selected to the chemistry and code rather than a single catalogue option.