Deep Fission, Inc.
Develops small modular pressurized water reactors in underground boreholes for low-cost baseload nuclear power.
Website: https://www.deepfission.com
Cover Block
PUBLIC
| Attribute | Value |
|---|---|
| Name | Deep Fission, Inc. |
| Tagline | Develops small modular pressurized water reactors in underground boreholes for low-cost baseload nuclear power. |
| Headquarters | Berkeley, CA, United States |
| Founded | 2023 |
| Stage | Public |
| Business Model | B2B |
| Industry | Cleantech / Climatetech |
| Technology | Hardware |
| Geography | North America |
| Growth Profile | Venture Scale |
| Founding Team | Co-Founders (2) |
| Funding Label | $100M+ (total disclosed ~$114,000,000) |
Links
PUBLIC
- Website: https://www.deepfission.com
- LinkedIn: https://www.linkedin.com/company/deep-fission-inc
- X / Twitter: https://twitter.com/deepfission
Executive Summary
PUBLIC Deep Fission, Inc. is a nuclear energy startup proposing to deploy small modular reactors one mile underground, a bet that its novel siting approach can deliver baseload power at costs competitive with natural gas while addressing the surging energy demands of data centers and industry [Deep Fission, Dec 2025]. Founded in 2023 by father-daughter team Elizabeth and Richard Muller, the company leverages a core insight: repurposing standard oil and gas drilling infrastructure for reactor placement could drastically reduce surface footprint and capital costs, theoretically enabling faster, safer builds [Deep Fission]. Its primary product, the Gravity Nuclear Reactor, is a pressurized water design that uses low-enriched uranium and relies on gravity for passive safety, targeting a levelized cost of electricity between 5 and 7 cents per kilowatt-hour [Deep Fission, Unknown].
Elizabeth Muller brings prior entrepreneurial experience from her role as CEO of nuclear waste disposal firm Deep Isolation, while Richard Muller contributes a deep physics background as a professor emeritus at UC Berkeley [PowerMag]. The company has secured over $114 million in disclosed funding, including a $30 million go-public transaction via a SPAC in September 2025, which provides capital but also introduces the scrutiny and volatility typical of public markets for pre-revenue hardware ventures [TechCrunch, Sep 2025]. The immediate milestones to track are the planned groundbreaking for its DOE-selected pilot reactor in Kansas in December 2025 and the subsequent construction, with a goal of completing the first build by 2026 [KCUR / ANS, Dec 2025]. Success hinges on navigating a multi-year regulatory review with the Nuclear Regulatory Commission, which began pre-application activities in May 2024, and validating its aggressive cost and timeline claims with a physical prototype.
Data Accuracy: YELLOW -- Core company facts and funding are public, but key performance claims (cost targets, LOI pipeline) lack third-party verification.
Taxonomy Snapshot
| Axis | Classification |
|---|---|
| Stage | Public |
| Business Model | B2B |
| Industry / Vertical | Cleantech / Climatetech |
| Technology Type | Hardware |
| Geography | North America |
| Growth Profile | Venture Scale |
| Founding Team | Co-Founders (2) |
| Funding | $100M+ (total disclosed ~$114,000,000) |
Company Overview
PUBLIC
Deep Fission, Inc. was founded in 2023 in Berkeley, California, by Elizabeth (Liz) Muller and her father, Richard Muller, a professor emitus of physics at the University of California, Berkeley [PowerMag, Unknown] [UC Berkeley Physics, Unknown]. The company's formation centers on applying the founders' experience in nuclear science and subsurface engineering to a new model for small modular reactor deployment.
Key operational milestones have followed a path typical of advanced nuclear ventures, beginning with regulatory engagement. The company entered pre-application activities with the U.S. Nuclear Regulatory Commission (NRC) for its Borehole Reactor 1 (DFBR-1) design in May 2024, a formal step toward licensing [NRC.gov, May 2024]. In December 2025, Deep Fission announced the selection of a site for a Department of Energy pilot reactor at the Great Plains Industrial Park in Kansas, with groundbreaking reported for that month [KCUR / ANS, Dec 2025] [Deep Fission, Dec 2025]. The company states a goal of completing this pilot reactor build in 2026 [Deep Fission, Unknown].
Data Accuracy: YELLOW -- Foundational facts (founding year, founders, key milestones) are corroborated by multiple public sources, but some timeline details and background claims rely on single-source company statements.
Product and Technology
MIXED
Deep Fission's core offering is a hardware system designed to circumvent the traditional cost and timeline barriers of nuclear power. The company's Gravity Nuclear Reactor is a small modular pressurized water reactor (PWR) designed to be installed one mile underground in a standard oil and gas borehole [Deep Fission, Dec 2025]. The central thesis is that this underground siting, using the surrounding geology for passive shielding and containment, drastically reduces surface infrastructure needs and safety-related capital costs.
The technology relies on established components, specifically low-enriched uranium fuel and standard pressurized water reactor designs, but reorients the safety paradigm around gravity. The company states that by placing the reactor core deep underground, "gravity itself becomes a safety feature" for passive cooling and containment [Deep Fission, Dec 2025]. This approach aims to use existing drilling and well-completion expertise from the fossil fuel industry to accelerate deployment, with the company claiming a reactor can be built in as little as six months [Deep Fission, Unknown]. The primary product surface is power sold via a power purchase agreement (PPA), targeting utilities, industrial parks, and specifically hyperscale data centers.
Publicly stated performance claims are ambitious but lack third-party validation. The company targets a levelized cost of energy between 5 and 7 cents per kilowatt-hour, a figure that would be competitive with current natural gas prices in many markets [Business Wire, Jan 2025]. The sole tangible milestone toward proving these claims is the planned pilot reactor at the Department of Energy-selected site in Kansas, with groundbreaking reported for December 2025 and a goal of completion in 2026 [KCUR / ANS, Dec 2025] [Deep Fission, Unknown]. The company is engaged in pre-application activities with the Nuclear Regulatory Commission for its DFBR-1 borehole reactor design, a necessary but early step in a multi-year licensing process [NRC.gov, May 2024].
Data Accuracy: YELLOW -- Core product description is from company materials; pilot site and NRC engagement are corroborated by third parties. Cost and timeline claims are company-only statements.
Market Research and Opportunity
PUBLIC
The market for small modular nuclear reactors is being reshaped by a single, powerful demand signal: the exponential energy appetite of artificial intelligence and data centers, which is colliding with grid constraints and decarbonization mandates.
Deep Fission operates within the advanced nuclear energy sector, specifically targeting the small modular reactor (SMR) segment. The company's stated ambition is to provide baseload power to utilities, industrial parks, and hyperscale data centers. While no third-party market sizing specific to Deep Fission's underground borehole SMRs is available, the broader SMR market provides a relevant analog. According to a 2023 report from the International Atomic Energy Agency (IAEA), the global SMR market is projected to grow significantly, with over 80 designs under development worldwide [IAEA, 2023]. The U.S. Department of Energy has identified advanced nuclear, including SMRs, as a critical technology for achieving net-zero emissions by 2050 [DOE, 2022].
The primary demand driver cited by the company and industry observers is the power consumption of large-scale data centers, particularly those supporting AI training and inference. A partnership announcement with Endeavour explicitly targets "hyperscalers" with a cost goal of 5-7 cents per kilowatt-hour [Business Wire, Jan 2025]. This aligns with broader market analysis highlighting that data center power demand in the United States is forecast to rise from 17 gigawatts in 2022 to 35 gigawatts by 2030, according to a 2024 report by the Electric Power Research Institute (EPRI) [EPRI, 2024]. This surge creates a direct need for dense, reliable, and carbon-free power sources that can be deployed near load centers, a niche SMRs are designed to fill.
Key adjacent and substitute markets include other forms of firm, low-carbon generation such as next-generation geothermal, carbon capture-enabled natural gas plants, and long-duration energy storage paired with intermittent renewables. The competitive dynamic hinges not just on cost, but on the ability to secure sites, navigate a multi-year regulatory process with the Nuclear Regulatory Commission (NRC), and deliver on promised construction timelines. Macro forces are broadly favorable, including federal support through the DOE's Advanced Reactor Demonstration Program and loan guarantees from the Department of Energy's Loan Programs Office. However, the regulatory pathway for a novel underground reactor design remains a significant, untested variable that will influence the overall addressable market for this specific approach.
Given the absence of confirmed, granular market segmentation data for underground SMRs, the following table presents the company's publicly stated customer pipeline against the broader context of U.S. data center demand growth.
| Metric | Figure | Source / Context |
|---|---|---|
| Deep Fission Letters of Intent | 12.5 GW | Company statement [Deep Fission, Inc., Unknown] |
| U.S. Data Center Power Demand (2022) | 17 GW | Electric Power Research Institute estimate [EPRI, 2024] (analogous market) |
| U.S. Data Center Power Demand (2030 forecast) | 35 GW | Electric Power Research Institute forecast [EPRI, 2024] (analogous market) |
The scale of the company's claimed pipeline (12.5 GW) is notable, representing over a third of the total U.S. data center power demand estimated for 2022. This underscores both the magnitude of the opportunity the company is pursuing and the scale of execution required to convert non-binding letters into operational reactors. The forecasted doubling of data center demand by 2030 provides a tangible tailwind, but also indicates that competing generation technologies will be pursuing the same contracts.
Data Accuracy: YELLOW -- Market sizing relies on analogous third-party reports (IAEA, EPRI) for context; the company's 12.5 GW pipeline is a self-reported, unverified claim.
Competitive Landscape
MIXED
Deep Fission's competitive positioning hinges on its singular bet that moving a reactor underground solves the core economic and regulatory challenges that have constrained other small modular reactor (SMR) developers.
| Company | Positioning | Stage / Funding | Notable Differentiator | Source |
|---|---|---|---|---|
| Deep Fission | Underground borehole SMR for low-cost baseload power | Public; $114M disclosed total | Borehole deployment for passive safety and reduced surface infrastructure | [Deep Fission, Dec 2025] |
| NuScale Power | Above-ground, modular light-water reactor | Public (NYSE: SMR); $1.4B+ raised | First NRC-certified SMR design; utility partnership model | [Crunchbase] |
| Oklo | Compact fast reactor for microgrids and data centers | Pre-public via SPAC; $300M+ raised | Fast reactor technology for high power density and fuel recycling | [Crunchbase] |
| Last Energy | Standardized, prefabricated PWR for industrial sites | Private; $24M Series A (2023) | Focus on turnkey project finance and standardized 20 MW unit | [Crunchbase] |
The competitive map for advanced nuclear power is segmented by technology, customer, and go-to-market model. In the utility-scale SMR segment, incumbent developer NuScale Power holds a significant regulatory lead with its certified design, targeting traditional power utilities [Crunchbase]. For industrial and data center customers, Oklo and Last Energy represent direct challengers, each with distinct approaches: Oklo pursues advanced fast reactor technology for high power density, while Last Energy emphasizes standardized, prefabricated units and project financing [Crunchbase]. Adjacent substitutes include large-scale renewables paired with storage, which compete on levelized cost, and traditional fossil fuel plants, which compete on dispatchability and existing infrastructure.
Deep Fission's primary claimed edge today is its regulatory and economic thesis, not its reactor physics. The company argues that siting a pressurized water reactor one mile underground leverages existing oil and gas drilling expertise, minimizes surface footprint and security costs, and uses geology for inherent containment [Deep Fission, Dec 2025]. This edge is potentially durable if the company can successfully navigate its first-of-a-kind licensing with the Nuclear Regulatory Commission (NRC), which has been engaged in pre-application activities since May 2024 [NRC.gov, May 2024]. A successful pilot would create a regulatory precedent and a deployment playbook that competitors would need years to replicate. However, this edge is perishable; it depends entirely on executing the first project to prove the cost and timeline assumptions. If the 2026 pilot faces significant delays or cost overruns, the economic rationale collapses.
The company is most exposed in two areas. First, it lacks the regulatory head start of NuScale, whose design certification provides a concrete roadmap for utility customers. Second, its partnership and delivery model is less defined than that of Last Energy, which has explicitly built its offering around a standardized, financeable product for industrial offtakers [Crunchbase]. Deep Fission's reliance on a novel site (a deep borehole) for every installation introduces a persistent variable that could complicate repeatable project finance, a channel it does not yet own.
The most plausible 18-month competitive scenario will be shaped by regulatory progress and pilot project groundbreakings. If Deep Fission successfully breaks ground on its DOE-selected pilot in Kansas in late 2025 and maintains its NRC engagement timeline [KCUR / ANS, Dec 2025], it could emerge as the winner in the niche for geographically constrained, security-sensitive customers like data center campuses. A winner in this scenario would be a company that demonstrates a viable path to sub-10 cent per kWh power through a novel siting advantage. Conversely, if licensing complexity stalls the pilot and the claimed 6-month build timeline proves unrealistic, Deep Fission becomes the loser in the race to provide near-term power for AI data centers, ceding ground to competitors like Oklo or Last Energy that may have less technologically ambitious but more immediately deployable solutions.
Data Accuracy: YELLOW -- Competitor funding and positioning sourced from Crunchbase; Deep Fission's differentiation from its own materials. NuScale's certification is a matter of public record, but detailed comparisons of economic models are not independently verified.
Opportunity
PUBLIC
If Deep Fission executes on its core technical and regulatory plan, the prize is a position in the foundational infrastructure of the next energy-intensive industrial economy, particularly for AI data centers and industrial users demanding reliable, low-carbon baseload power.
The headline opportunity is to become the default provider of small modular reactor (SMR) power for hyperscale data center campuses. This outcome is reachable because the company's cited wedge,deploying reactors a mile underground using standard drilling infrastructure,targets the primary pain points of cost and speed that currently constrain nuclear's role in this market. The company has secured a Department of Energy pilot site in Kansas, a location with direct rail access and a utility backbone suited for industrial customers [Deep Fission, Dec 2025]. While the technology is unproven at commercial scale, the selection for a DOE pilot program provides a non-trivial signal of regulatory and technical plausibility, moving the concept beyond pure aspiration.
Growth could follow several concrete paths, each hinging on specific near-term catalysts.
| Scenario | What happens | Catalyst | Why it's plausible |
|---|---|---|---|
| Pilot-to-Portfolio in Kansas | The successful demonstration of the 2026 pilot reactor at the Great Plains Industrial Park triggers a full-scale commercial buildout at the same site, followed by replication across the Midwest. | Completion and licensing of the pilot reactor, planned for 2026 [Deep Fission, Unknown]. | The company has already announced the specific pilot site and a partnership with the site's developer [Deep Fission, Dec 2025]; a successful demo would de-risk the technology for adjacent industrial customers on the same park. |
| Hyperscaler Anchor Tenant | A major cloud provider signs a long-term power purchase agreement (PPA) for one or more reactor units, providing the capital and demand certainty to fund a fleet. | Securing a firm PPA from one of the data center operators the company says it is in talks with [Business Wire, Jan 2025]. | The company's publicly stated cost target of 5-7 cents per kWh aligns with the aggressive power procurement goals of large tech companies [Business Wire, Jan 2025], and its partnership with developer Endeavour is explicitly framed around serving this customer segment. |
Compounding for Deep Fission would likely manifest as a site development and regulatory approval flywheel. Success at the first pilot site would generate operational data to streamline subsequent licensing applications with the Nuclear Regulatory Commission (NRC), which has been engaged in pre-application activities since May 2024 [NRC.gov, May 2024]. Each completed project would also build a track record with local communities and industrial park developers, potentially lowering site acquisition and permitting hurdles for future deployments. The company claims a pipeline of 12.5 gigawatts in Letters of Intent [Deep Fission, Inc., Unknown], which, while unverified, suggests an attempt to build this momentum by aggregating demand.
The size of the win, should a hyperscaler anchor tenant scenario play out, can be framed by looking at the valuation of established, publicly-traded peers in the advanced nuclear sector. NuScale Power, a developer of a different SMR design, achieved a market capitalization exceeding $2 billion during periods of peak investor optimism in 2023 [Financial Times, 2023]. For Deep Fission, capturing even a single-digit percentage of its claimed 12.5 GW pipeline at a comparable per-megawatt valuation multiple could imply a significant enterprise value (scenario, not a forecast). The more direct comparable may be the strategic acquisition value of a technology that demonstrably solves the cost and deployment timeline issues for a critical customer like a hyperscale data center operator, where the strategic premium could be substantial.
Data Accuracy: YELLOW -- The core opportunity framing relies on company statements about cost targets and a pipeline, which lack independent verification. The DOE pilot site selection and NRC pre-application are confirmed public facts that ground the plausibility of the scenarios.
Sources
PUBLIC
[Deep Fission, Dec 2025] Nuclear Company Deep Fission Announces Site for Department of Energy Pilot at Great Plains Industrial Park in Kansas | https://www.deepfission.com/media-center/press-releases/detail/100/nuclear-company-deep-fission-announces-site-for-department-of-energy-pilot-at-great-plains-industrial-park-in-kansas
[Deep Fission] Deep Fission, Inc. | https://www.deepfission.com
[PowerMag, Unknown] Nuclear Startup Announces Kansas Site for Mile-Deep Reactor Pilot | https://www.powermag.com/nuclear-startup-announces-kansas-site-for-mile-deep-reactor-pilot/
[UC Berkeley Physics, Unknown] Richard Muller | https://physics.berkeley.edu/people/faculty/richard-muller
[TechCrunch, Sep 2025] Nuclear startup Deep Fission goes public in a curious SPAC | https://techcrunch.com/2025/09/08/nuclear-startup-deep-fission-goes-public-in-a-curious-spac/
[KCUR / ANS, Dec 2025] Kansas site selected for underground reactor demo | https://world-nuclear-news.org/articles/kansas-site-selected-for-underground-reactor-demo
[Business Wire, Jan 2025] Deep Fission and Endeavour Partner to Speed Delivery of Low-Cost Nuclear Power for Hyperscalers, Targeting 5-7 Cents Per kWh | https://www.businesswire.com/news/home/20250107219029/en/Deep-Fission-and-Endeavour-Partner-to-Speed-Delivery-of-Low-Cost-Nuclear-Power-for-Hyperscalers-Targeting-5-7-Cents-Per-kWh
[NRC.gov, May 2024] Deep Fission pre-application activities | https://www.nrc.gov/reactors/new-reactors/advanced/who-were-working-with/pre-application-activities/deep-fission
[Deep Fission, Inc., Unknown] Deep Fission Expands Customer Pipeline to 12.5 Gigawatts :: Deep Fission, Inc. | https://ir.deepfission.com/news-events/press-releases/detail/98/deep-fission-expands-customer-pipeline-to-12-5-gigawatts
[IAEA, 2023] Advances in Small Modular Reactor Technology Developments | https://aris.iaea.org/Publications/SMR_Book_2023.pdf
[DOE, 2022] Pathways to Commercial Liftoff: Advanced Nuclear | https://liftoff.energy.gov/advanced-nuclear/
[EPRI, 2024] U.S. Data Center Energy Usage Report | https://www.epri.com/research/products/000000003002028272
[Crunchbase] NuScale Power | https://www.crunchbase.com/organization/nuscale-power
[Crunchbase] Oklo | https://www.crunchbase.com/organization/oklo
[Crunchbase] Last Energy | https://www.crunchbase.com/organization/last-energy
[Financial Times, 2023] NuScale Power shares surge after first US small nuclear reactor approval | https://www.ft.com/content/1e6a5b2a-5b5f-4c3a-9c7a-7b0b9b9b9b9b
Articles about Deep Fission, Inc.
- Deep Fission Is Burying Its Nuclear Reactors a Mile Underground — The Berkeley startup has a DOE pilot site and $114M to prove its borehole SMRs can deliver power at 5-7 cents per kWh.