From Pilot to Industrial Scale: TheStorage's Sand Battery

On January 30, 2026, Finnish cleantech startup TheStorage announced the installation of its first industrial-scale sand-based heat storage system at a brewery in Finland. As reported by PV Magazine, the technology converts renewable electricity into high-temperature heat, stores it in sand, and delivers it on-demand for industrial processes — reducing energy costs by up to 70% and carbon emissions by up to 90%.

The system is scalable from 20 MWh to 500 MWh with charging power from 1 MW to 20 MW, making it suitable for a wide range of industrial heat applications. The pilot produces fossil-free steam for brewery production lines, demonstrating a practical pathway to decarbonizing industrial process heat — a sector accounting for roughly 20% of global energy consumption.

Thermal Storage vs Electrochemical BESS: An Economic Comparison

For industrial heat applications, sand-based thermal storage competes with different technologies than grid-scale Li-ion BESS:

  • Sand thermal storage: $20-40/kWh (thermal), 50+ year lifetime, 90-95% round-trip efficiency (thermal-to-thermal), 20-500 MWh scale
  • Li-ion BESS + electric boiler: $80-120/kWh (electrochemical) + $50-100/kW (boiler), 15-20 year life, 70-85% power-to-heat-to-power efficiency
  • Natural gas boiler: $50-100/kW CAPEX, $8-15/MMBtu fuel cost, 85-92% thermal efficiency

The levelized cost of heat (LCOH) for sand storage depends critically on the number of annual cycles and grid electricity cost. At 250 cycles/year with $25/MWh electricity, sand storage delivers heat at $30-40/MWh (thermal) — competitive with gas at $8/MMBtu ($27/MWh) and increasingly attractive as carbon pricing rises.

Key insight: TheStorage's sand battery captures electricity when abundant and inexpensive (e.g., midday solar overgeneration at €10-20/MWh) and stores it at 500-600°C. This is a 4-8 hour LDES system for heat applications, requiring no lithium, cobalt, or vanadium — just sand, steel, and resistive heating elements.

LDES Dispatch Modeling in Hybrid Systems

Unlike electrochemical BESS which charges and discharges electricity, thermal storage is primarily a one-way conversion (electricity-to-heat). This changes the dispatch optimization problem. In Energy Optima's framework, the thermal storage asset would be modeled as:

  • A deferrable electric load — the resistive heating element consumes electricity when prices are low, functioning as a controllable load rather than a dispatchable generator
  • A thermal capacitor — sand stores energy with minimal self-discharge (<2% per day) over 6-48 hour periods, making it a genuine LDES asset
  • A gas displacement tool — the primary value is avoiding natural gas consumption at €8-12/MMBtu

Integrating Thermal Storage with PV

For a brewery or industrial facility with on-site solar, the optimization logic becomes:

  • PV generation directly powers production during daylight hours
  • Excess PV (typically 11 AM to 3 PM) charges the sand battery rather than exporting at low wholesale prices
  • The sand battery discharges heat at night or during cloudy periods, displacing gas boiler operation
  • During winter with low PV output, the sand battery can charge from grid at nighttime off-peak rates

Energy Optima's Non-Battery Storage Support

Energy Optima's platform handles non-battery storage technologies through flexible system configuration:

  • Custom asset definitions — define thermal storage with its own efficiency, self-discharge, and duty cycle parameters
  • Multi-vector optimization — the EMS dispatch engine handles electricity and thermal energy flows simultaneously
  • Financial comparison — run side-by-side scenarios comparing sand thermal vs Li-ion BESS vs gas-only for the same industrial heat load