Decarbonising industrial heat requires a rare type of engineer. There are roughly 1,600 of them worldwide, most clustered around a handful of large employers in Silicon Valley. Antora Energy sits in the middle of that cluster — and the hiring data shows what that proximity is worth.
Industrial heat is responsible for around 20 per cent of global energy demand and remains one of the hardest parts of the economy to decarbonise. Factories, chemical plants, steel mills and food producers need high-temperature heat around the clock — and until recently, the only reliable way to generate it was to burn fossil fuels. Thermal batteries change that equation. They store cheap renewable electricity as heat, held in insulated carbon blocks at temperatures up to 2,400°C, and release it on demand over hours or days. The technology is straightforward in concept and brutally difficult in execution.
Antora Energy, founded in 2017, builds and deploys thermal batteries for industrial customers. In August 2026 it closed a $550 million Series C — an oversubscribed round co-led by G2 Venture Partners and Eclipse — shortly after commissioning a 5 GWh project at POET’s bioprocessing facility in South Dakota, one of the largest battery storage installations in the world. The company has 30 open roles and is building a second US manufacturing facility.
The question Zeki’s data answers is not whether Antora is a credible company — the funding and the deployment record settle that. The question is whether the talent behind its growth is as strong as the momentum suggests, and whether the risks accumulating quietly in the workforce are visible before they matter.
The talent pool is small and geographically fixed
Thermal, power and high-temperature engineering is a narrow discipline. The global pool of specialists — the people whose careers have been built around the specific combination of thermodynamics, materials science and high-temperature systems that a heat battery requires — numbers around 1,600. They are not evenly distributed. Seventy-two per cent work in the United States. Silicon Valley is the dominant centre, with further clusters around Tesla’s sites in Austin and Reno, and a grid-power belt running through the industrial South-East and North-East.
Three employers hold most of this group. Tesla accounts for roughly half the relevant talent pool. GE Vernova holds about a fifth. Siemens Energy accounts for a further six per cent. The six largest employers together cover 83 per cent of all specialists in the field. Antora Energy — headquartered a few miles from Tesla’s Fremont plant — is competing for the same engineers as SpaceX, Blue Origin, the hardware teams at Amazon, Meta and Nvidia, and battery peers like Redwood Materials and Form Energy.
The hiring data shows Antora is winning more of that competition than its peers. Its Tesla alumni share, at 16 per cent of the workforce with prior Magnificent Seven experience, is roughly double the comparator median — and 64 per cent of those alumni came from Tesla specifically. Rondo Energy, its closest rival and the only other California-based comparator, has 11 per cent. Kraftblock, based in Germany, and Brenmiller Energy, based in Israel, have none. This is not primarily a testament to distinctive talent magnetism. It is a testament to being in the right place.
Percentage of current workforce hired by year, all companies in focus. Source: Zeki.
Growing fast, hiring well — for now
Antora raised more than any comparator and hired faster than any comparator. Thirty-nine per cent of its current workforce joined in 2024, the year of its $150 million Series B and its first major manufacturing scale-up. A further 23 per cent joined in 2025. The company now has more than 230 employees — the largest team in the set by a considerable margin.
The quality of that hiring has held up. Just over half of Antora’s current workforce has prior experience in thermal storage or clean-energy hardware — the highest insider rate in the comparator set and significantly ahead of Rondo Energy at around 40 per cent. Its engineering bench scores well on the composite measure Zeki uses: PhD share at 19 per cent, average applied experience of 9.8 years, and 40 per cent of engineers with directly relevant prior experience in thermal storage or clean-energy hardware. On all three measures it leads or matches Rondo Energy and comfortably outscores Fourth Power, the most research-heavy comparator.
The founding team adds to this. Justin Briggs and David Bierman hold Stanford and MIT PhDs in thermophotovoltaic energy conversion — the specific technology that distinguishes Antora’s system, allowing it to convert stored heat back to electricity as well as deliver it as process heat. This is a meaningful differentiator: Rondo Energy’s battery produces heat and steam only. Antora’s produces electricity too, which substantially broadens the customer base it can address.
The one gap the data identifies is senior leadership continuity. In early 2026 Antora lost its CFO, Rene Griemens, who left to co-found Arcticar, and Conrad Brandt, its head of finance for four years, who left to become CFO at Nevados. Both engineering and product leaders had departed in late 2023: Adrienne Tsier, vice president of systems engineering who had grown the team from 20 to 60, and Mark Preston, senior vice president of product development. These are not catastrophic losses individually, but the pattern is worth watching as the company scales into the deployment phase that its Series C is designed to fund.
The cautionary tale next door
Brenmiller Energy exists in the same sector, is publicly listed on Nasdaq, and is travelling in the opposite direction. It carries an accumulated deficit of $116 million, reported no revenue in the first half of 2026, has undergone three reverse stock splits in 2026 alone to stay above Nasdaq’s minimum bid price, and in May 2026 its founder Avi Brenmiller handed the CEO role to his son Nir — whose background before joining the family company was as an IT manager. Its co-founders are Avi’s sons, neither with directly relevant experience. Headcount has fallen steadily: from roughly 80 in 2020 to around 30 today.
Brenmiller is not an isolated case. Heliogen, an AI-enabled concentrated solar thermal storage company, never completed a commercial-scale plant and was sold to Zeo Energy for $10 million in 2025 after its demonstration project was cancelled on cost grounds. SolarReserve, a molten-salt storage company that licensed Rocketdyne technology and built the Crescent Dunes plant with a $737 million DOE loan guarantee, was brought down by recurring storage-tank failures; it ceased operations in 2020 and the plant vehicle entered Chapter 11 bankruptcy.
The pattern across these failures is consistent: wrong or inexperienced leadership, inability to retain the technical talent needed to solve hard engineering problems at commercial scale, and a GTM function that never developed the depth to sustain revenue. The talent scorecard is legible years before the balance sheet reflects it.
The one gap Antora has not closed
Antora’s GTM presence is almost entirely domestic. Its commercial team was built primarily for the United States market, accelerating after the 2024 Series B. Only two commercial hires are based abroad — a business development director in Madrid hired in July 2026, and a commercial development manager in Sydney. The rest work in the US or remotely.
Rondo Energy, which makes roughly the same product, has taken the opposite approach. Thirteen of its 18 commercially placed hires sit outside the US — in Spain, Australia, the UK, Switzerland, the UAE and Argentina. Rondo runs its European delivery hub from Madrid, backed by a supply agreement with Portuguese utility EDP and European Investment Bank-financed projects in Denmark and Germany. It counts Rio Tinto among its strategic investors and has commercial staff in Australia pursuing the mining and heavy industry sector.
This is not simply a matter of ambition. The business models differ in a way that shapes the hiring logic. Antora supplies heat under long-term contracts rather than selling hardware — which concentrates commercial effort on signing anchor customers and developing individual project sites. That model, at this stage, is US-focused by design. Rondo sells heat and steam to industrial customers and has moved international earlier, partly because its European pipeline is more developed and partly because Rio Tinto’s involvement pulls it toward Australia’s heavy industry market.
The talent question for investors is whether Antora’s commercial concentration in the US is a deliberate sequencing choice or a structural gap that will be harder to close later. The $550 million Series C gives it runway to find out. The open role list — 30 positions, almost all engineering and manufacturing, mostly in San Jose — suggests the immediate priority is scaling the factory and the deployment pipeline, not the international commercial footprint. That is the right call for where the company is. It is also the gap that Rondo Energy is using to build a head start.
About this analysis. This article draws on Zeki’s diagnostic report on Antora, benchmarking Antora Energy against Rondo Energy, Fourth Power, Kraftblock, Electrified Thermal Solutions and Brenmiller Energy. Underlying data is compiled from publicly available sources including hiring records, job postings and professional profiles.
The full report includes the highest-scoring engineers at Antora Energy, senior GTM hire profiles and open role data.