The Utilidors of the Bioeconomy: POET, Antora Are Building the Hidden Operating Systems of Industrial Decarbonization

by Jim Lane (Biofuels Digest) ... Last week in Big Stone City, South Dakota, POET and Antora Energy quietly commissioned one of the world’s largest thermal energy storage systems: a 5-gigawatt-hour industrial battery designed not to power roller coasters or castle lights, but to capture something factories normally throw away — timing. Or perhaps more accurately: an opportunity to prevent waste from becoming a wasted opportunity.

The system, installed at POET’s bioprocessing facility in Big Stone City, converts low-cost or surplus renewable electricity into stored industrial heat. Instead of relying on lithium-ion chemistry, Antora stores energy inside insulated blocks of solid carbon heated to temperatures between 1,000 and 2,000 degrees Celsius. Unlike chemical batteries dependent on globally constrained critical minerals, the system relies primarily on abundant carbon materials sourced domestically through existing industrial supply chains.

Ethanol plants are not primarily electrical machines. They are thermal organisms. Distillation columns, evaporators, dryers, cook systems, and fermentation infrastructure consume heat relentlessly, day and night. A typical 60-to-70-million-gallon-per-year dry-mill facility may require 20 to 25 megawatts of continuous thermal energy, most of it supplied by fossil gas combustion.

Antora’s wager is that intermittent renewable power can be transformed into something industrial operators value far more: continuous, dispatchable heat.

The scale of the Big Stone City deployment is difficult to overstate. The installation consists of hundreds of modular thermal battery units storing enough energy to deliver industrial-scale heat output continuously over multiple days. At full operation, the system is capable of fundamentally altering the thermal economics of a modern biorefinery. And the economics extend far beyond fuel savings alone.

By replacing fossil combustion with stored renewable heat, facilities can sharply reduce their Carbon Intensity scores under programs such as California’s Low Carbon Fuel Standard and the federal Section 45Z Clean Fuel Production Credit. A Midwest ethanol plant lowering its CI score from roughly 60–70 gCO₂e/MJ into the sub-40 range can unlock incremental revenues estimated at $0.12 to $0.18 per gallon — potentially generating $8 million to $12 million annually for a single 65-million-gallon facility.

Eric McAfee has described this evolution as “Third Generation” bioenergy — the transformation of ethanol facilities from fuel plants into integrated carbon-management platforms capable of functioning as industrial carbon siphons. In that framing, the thermal battery is not simply a cleaner boiler. It is part of a larger redesign of how industrial carbon, electricity, heat, and agricultural systems interact. The engineering logic is increasingly persuasive.

Capturing surplus renewable electricity and converting it into industrial heat sounds straightforward in principle. In practice, it requires synchronizing utility pricing, transmission availability, thermal integration, tax incentives, carbon markets, construction schedules, and long-duration financing into a single continuously operating industrial organism. That is not a boiler replacement. It is a partial redesign of the industrial energy architecture surrounding the plant itself.

To make the system work economically, Antora partnered with Otter Tail Power to create a bespoke electric rate structure approved by the South Dakota Public Utilities Commission. The arrangement allows the thermal batteries to rapidly charge during periods of surplus generation without shifting costs onto other utility customers. In effect, the project turns the ethanol plant into a flexible grid-balancing asset capable of absorbing excess renewable generation while stabilizing industrial energy demand. Yet the capital realities remain daunting.

Estimated installed costs for thermal storage systems of this magnitude range between roughly $100 and $150 per thermal kilowatt-hour, placing a 5 GWh deployment somewhere between approximately $500 million and $750 million in capital expenditure before financing costs, integration expenses, or supporting infrastructure are fully considered. A conventional natural gas boiler may cost only a few million dollars and arrives as relatively standardized industrial equipment. A gigawatt-scale thermal storage installation, by contrast, is currently a monumental civil engineering project involving utility coordination, thermal integration, grid negotiations, tax structuring, and long-duration capital commitments.

In technology terms, Big Stone City increasingly looks proven. In financing terms, it still resembles a moonshot assembled from stacked incentives, bespoke utility structures, federal tax credits, and unusually sophisticated counterparties.

The original technology platform benefited from early Department of Energy support during the first Trump Administration, helping de-risk initial development. To complete commercial deployment, major climate-tech investor Grok Ventures stepped forward with project-level financing support. The economics further depend on a latticework of federal incentives including Sections 45X, 45Z, and the Investment Tax Credit, alongside favorable utility arrangements capable of monetizing off-peak renewable power.

That complexity matters. POET is not a typical ethanol producer. It operates 35 bioprocessing facilities, exports globally, and possesses the engineering depth, balance sheet strength, and operational sophistication necessary to navigate multi-layered industrial finance structures. Smaller independent producers may not.

This is the hidden fragility surrounding industrial decarbonization. READ MORE

However, the high temperatures required for many industrial processes make them difficult to abate emissions from, as this requires a lot more energy and an effective storage medium. Antora has claimed that its technology operates at high enough temperatures to meet the requirements of ‘hard-to-abate’ industries such as steel and cement production.

In a blog for the World Economic Forum at the beginning of this year, Antora CEO and co-founder Andrew Ponec wrote that he and his co-founders “studied every type of battery technology—from advanced chemistries based on lithium and sodium to approaches using molten salt and iron,” when they started up the company.

“What we found surprised us: The cheapest, most scalable way to store huge amounts of energy is to heat up some of the most abundant materials on earth,” Ponec wrote.

The Big Stone project in South Dakota went from the start of construction to commissioning in less than a year, another benefit of TES technology that CEO Ponec talked up in his World Economic Forum blog. Ponec said the speed of deployment made the thermal batteries a good solution for AI data centre developers, who prize speed-to-power. READ MORE