Two electrically heated firebrick battery units will supply heat to a high-temperature chamber at a Holcim cement plant early next year, in what the companies describe as the first deployment of thermal-energy storage for this stage of cement production. Neither party named the facility, the investment size, or the delivery schedule beyond that window.

Boston-based Electrified Thermal Solutions announced the deployment on Tuesday. CEO and co-founder Daniel Stack said the units will cover the calcination process, which typically requires 900–1,500°C. Each unit matches the capabilities of the company's first commercial-scale system in San Antonio, which stores 20 megawatt-hours of heat at up to 1,800°C (3,270°F).

If the project performs, Stack said it will be "a step change in what's been done to actually electrify cement and concrete production."

The San Antonio system, installed at the Southwest Research Institute, has logged more than 1,000 operating hours — the proof points Electrified Thermal needed before signing the Holcim deal, announced roughly nine months after that unit's unveiling.

The technology itself is simple in outline: electricity heats insulated stacks of metal-oxide firebricks, drawing grid power during off-peak hours when wind and solar output is often highest. Air blown across the bricks discharges the stored heat, and the hot gas pipes directly into industrial equipment. Stack declined to give project costs but said the batteries carry a "very compelling cost profile" in European markets and anywhere electricity costs less than natural gas.

Cement accounts for roughly 8% of global CO2 emissions. About 60% of that comes from process chemistry — limestone decomposing into calcium oxide and CO2 in the kiln — which firebrick heat cannot address. The remaining share comes from burning natural gas or coal to fire kilns and furnaces. That combustion segment is the target of the Holcim deployment.

"Electrifying high-temperature industrial heat is one of the advanced technologies we are incorporating in our decarbonization strategy, and this deployment allows us to evaluate its potential," Ram Muthu, Holcim's head of operational excellence, said in a statement.

Holcim is an investor in Electrified Thermal and is backing several other clean-cement startups, including MIT spin-out Sublime Systems, which aims to replace kilns entirely with an electrochemical process.

A crowded field

Electrified Thermal is one of roughly two dozen startups building thermal storage for industrial heat or grid discharge. California-based Antora Energy raised $550 million in July to scale its own heat batteries. Six other firms have raised at least $53.7 million combined in venture and equity funding this year, according to Cleantech Group.

In cement specifically, Rondo Energy began operating a 33-MWh unit at a plant in Thailand last November, charging from the grid and a nearby floating solar farm. Unlike Electrified Thermal's direct-heat approach, Rondo's system produces superheated steam to drive a turbine and generate electricity.

Zainab Gilani, an energy and power research associate at Cleantech Group, said market outcomes hinge on natural gas prices, local decarbonization policy, renewable availability, and electricity costs. "These factors, in addition to the specific demand for power and heat by industrial customers, all contribute to how successful projects will be," she said.

The Holcim project is Electrified Thermal's third industrial partnership. The company is testing its battery with steelmaker ArcelorMittal — another investor — at an R&D facility in Spain, and Stack declined to name the third partner. Brazilian iron-ore producer Vale is also a backer.

"We see the road map for how we can electrify every portion of the cement industry," Stack said. "We're looking forward to walking that path with Holcim and with our partners in the other major industrial verticals that have so far been unachievable with electric heat."

The commissioning date to watch is early next year, when the unnamed Holcim plant becomes the first test of whether firebrick heat can displace fossil-fired calcination at operating scale — and whether the levelized cost holds up against the gas prices that govern the technology's addressable market.