Rondo’s 100 MWh Thermal Battery Cuts Industrial Heat Costs by 40%

Industrial operators face rising fuel bills, volatile gas markets, and pressure to decarbonize. Rondo Energy’s new 100 MWh bricks-based thermal battery in Borrego Springs, California, delivers on all fronts: it charges from an on-site 25 MW solar array in under 4 hours, discharges up to 24 hours per day at >1,000 °C, and achieves a 97.3% round-trip efficiency. After 10 weeks of continuous operation, Chevron’s enhanced oil recovery steam loop reports 40% lower fuel costs and zero Scope 1 emissions from the heat source.

Business Impact

  • Cost reduction: By shifting 80% of steam generation from natural gas (at $7/MMBtu) to off-peak solar charging, facility managers report a 40% drop in heat tariffs, translating to $1.2 million in annual savings.
  • Carbon avoidance: Displacing 10 MMBtu/hour of gas eliminates 15,000 tons of CO₂ yearly, supporting Scope 1 targets and offsetting expensive carbon allowances.
  • Operational resilience: Off-grid charging eliminates interconnection delays—accelerating project timelines by 12–18 months versus traditional renewables plus grid upgrade approaches.

Site Details and Performance

Installed in September 2023 at Rondo’s pilot location in Borrego Springs, the 100 MWh unit pairs with a 25 MW photovoltaics array. Key metrics:

  • Charge cycle: 4 hours at peak solar output to reach full storage.
  • Discharge window: 24 hours of continuous steam delivery at 10 bar, 350 °C, or high-temp feed at >1,000 °C for process heat.
  • Throughput: Up to 3 cycles per day (≈1,000 cycles/year) with minimal degradation.
  • Efficiency: 97.3% electricity-to-heat round-trip, validated by independent tests from NREL.

“Rondo’s demonstration proves that bricks-based thermal energy storage can scale to the demands of heavy industry,” says Dr. Emily Crawford, Senior Analyst at the U.S. National Renewable Energy Laboratory (NREL). “This bridges the gap between lab prototypes and full-scale deployment.”

Scaling TES Across Europe

Building on California success, Rondo has three European projects underway:

  • Covestro Leverkusen (Germany): 50 MWh unit, commissioning Q2 2024 for chemical process heat.
  • Rotterdam Paper Mill (Netherlands): 75 MWh installation, expected online by Q4 2024 to supply 150 °C steam.
  • Holcim Valencia (Spain): 120 MWh system for cement kiln pre-heating, scheduled Q1 2025.

Meanwhile, Rondo’s Rayong, Thailand factory ramped up production in January 2024, offering 2.4 GWh/year of modular bricks—enough capacity for over 20 large thermal batteries annually.

Real-World Benefits

Facilities in food & beverage, pulp & paper, mining, and district energy can retrofit TES alongside existing boilers to:

  • Offset peak gas use without process redesign.
  • Lock in low Levelized Cost of Heat (LCOH) by marrying PPAs for solar or wind with thermal storage.
  • Accelerate decarbonization even in regions with grid constraints or high connection fees.

Early adopters report payback periods under 5 years, IRRs above 15%, and predictable cash flows insensitive to gas-price spikes.

Next Steps for Leaders

To capitalize on TES, energy and operations executives should:

  1. Map heat loads: Identify thermal demands above 5 MW and >6,000 full-load hours annually.
  2. Model LCOH scenarios: Compare gas-fired vs. solar-charged TES, including carbon pricing and volatility safeguards.
  3. Assess grid workarounds: Evaluate behind-the-meter or off-grid renewables to bypass interconnection bottlenecks.
  4. Conduct site audits: Confirm space, permits, safety zones for high-temp brick modules, and tie-in to steam headers.
  5. Secure incentives: Leverage industrial decarbonization grants, storage tax credits, and renewable subsidies.
  6. Issue RFPs: Engage Rondo and peers for performance guarantees on capacity, efficiency, and delivery timeline.
  7. Plan modular roll-outs: Start with a pilot tranche covering 20–30% of heat load, with expansion options pre-negotiated.
  8. Align governance: Integrate TES into sustainability goals, attribute reductions to Scope 1, and claim RECs/GO where eligible.

Technical & Economic Appendix

How Bricks-Based TES Works: Electricity heats dense ceramic bricks via resistive elements to >1,000 °C. Heat is stored in the brick matrix with <2% daily losses. On discharge, compressed air passes through the bricks, capturing stored heat to generate steam or high-temperature gas for industrial processes. Modular design allows parallel staging for continuous output.

Modeled LCOH Comparison: For a 10 MW thermal load (8,000 operating hours/year), a gas boiler at $7/MMBtu yields a heat cost of ~$30/MWh_th. Charging a 100 MWh TES with onsite solar at $25/MWh_e plus storage CAPEX spreads to $20/MWh_th. Including a carbon price of $50/tonne tilts economics further in TES’s favor, delivering stable, bankable heat pricing.

Contact Rondo Energy today to explore a pilot, secure performance data, and lock in industrial heat at predictable, low-carbon rates.