DIU Project Janus – Advanced Nuclear Microreactor Power Plant Prototyping
Executive Summary:
Project Janus is soliciting commercial solutions to design, prototype, and deploy advanced nuclear Microreactor Power Plants (MPPs) that can provide continuous, resilient power across Army installations. Awarded vendors will prototype both a First-of-a-Kind (FOAK) and a Second-of-a-Kind (SOAK) MPP, leading to potential follow-on production and long-term power purchase agreements. Solution Briefs are due December 15, 2025, so companies should begin preparing ASAP.
How much funding would I receive?
DIU does not publish fixed award amounts, but nuclear prototyping OTAs typically fall within the multi-million to tens-of-millions range, depending on complexity and vendor contributions.
Importantly, DIU OTAs can lead directly to large follow-on production contracts or long-term electricity PPAs without further competition, enabling far greater lifetime contract value.
What could I use the funding for?
Problem Statement
Ensuring consistent, resilient energy across military installations and operational theaters has become an increasingly complex challenge for the U.S. military. Aging infrastructure, dependence on vulnerable civilian power grids, complex liquid fuel logistics, and rising energy demands from advanced technologies all threaten mission assurance. Frequent electricity outages, grid disruptions, and limited backup capacity jeopardize critical systems responsible for command, control, communications, and logistics. This directly undermines readiness, training, and operational effectiveness. These vulnerabilities underscore the urgent need for secure, scalable, and independent energy solutions that ensure continuous power for the warfighter to operate anytime, anywhere, regardless of external grid instability or supply chain disruptions.
The U.S. Army, alongside the Defense Innovation Unit, seeks to prototype Microreactor Power Plant(s) (MPPs) capable of developing a suite of advanced nuclear power plant energy solutions to meet the needs of the U.S. Department of War (DoW). These MPPs will leverage recent advances in the nuclear industry to provide continuous and reliable power in all DoW scenarios and will be demonstrated on a military installation within the United States by 2030.
Background
On 23 May 2025, four executive orders (EOs) were issued that aimed at modernizing America’s nuclear energy posture, with direct implications for the Army and the broader DoW. In particular, EO 14299 Deploying Advanced Nuclear Reactor Technologies for National Security, states that “it is the policy of the United States to ensure the rapid development, deployment, and use of advanced nuclear technologies to support national security objectives, such as the protection and operation of critical infrastructure, critical defense facilities, and other mission capability resources.” These orders represent a strategic shift towards immediately and impactfully leveraging advanced nuclear technologies. Meeting the objectives of EO14299 requires a focus on both installation and operational energy goals through a coordinated prototype program that leverages MPP technologies to address the Department of War’s energy needs.
Project Approach
The broader Department of the Army’s Janus program objective is to develop a suite of prototype solutions for MPPs that can supply power for both installations and non-permanent operations. The Janus project approach under the DIU CSO will use an iterative prototype development process to provide a clear path to transition of the successful commercially demonstrated technology solutions. “Suite” refers to the DoW’s intent to select multiple reactor designs for the OTA Agreement, each to be paired with an Army installation by the Army after contract award. This will involve prototyping a First of a Kind (FOAK) MPP under the Army’s regulatory authority, followed shortly after by a Second of a Kind (SOAK) MPP, also using the Army’s regulatory authority. The Department is seeking fission-based solution sets for installation and defense purposes.
Vendors will be paired with Army installations after the OTA contract award. Vendors will develop their FOAK prototype for demonstration on that installation and commence design of the SOAK prototype near the end of FOAK design. The SOAK prototype is expected to build on lessons learned from the FOAK and include design changes from the FOAK prototype, through iterative prototyping.
Vendor solutions submitted under the AOI are highly encouraged to use the FOAK and SOAK approach in their proposals, and discuss the path from SOAK to Nth-of-a-kind production. Solutions may utilize the operating life of both the FOAK and SOAK MPPs in series to reach the 30-year lifetime power generation, assuming continuity of power across the 30-year period.
The Army will be announcing the selection of the initial group of installations for the Janus project MPP prototypes at a later date. Vendors are prohibited from contacting or responding to queries from the installations regarding any aspect of CSO HQ084520SC001 or the Janus project. Vendors who do not comply with the prohibition may be removed from participation in the Janus Project.
Project Objectives
The Department is seeking solution briefs for the full lifecycle of MPPs that would notionally start operations at an Army installation located in the United States before the end of calendar year 2030. Solution briefs should include all stages of an MPP’s lifecycle: design, testing, regulation, construction, operations, deconstruction, and returning the site to an unrestricted release status.
The objectives of the prototype include:
Provide mission assurance through energy resilience for a range of defense applications.
Assemble and operate prototype MPPs on military installations within the United States to demonstrate the capability of the MPP designs to provide safe, secure, reliable, and environmentally compliant electricity and thermal energy (if needed) in support of readiness goals for mission critical assets.
Engage with the government and privatized distribution providers, transmission providers, and commodity providers currently serving U.S. Military installations to facilitate seamless and resilient energy regardless of commercial grid conditions.
Final solutions will follow a process under the U.S. Army Regulatory Authority for the entire lifecycle. The U.S. Army’s regulatory authority is derived from section 91b of the Atomic Energy Act (42 U.S.C. § 2121(b)), as implemented pursuant to the Presidential Directive of 23 September 1961. Vendors will follow the Army regulatory process as documented in AR 50-7 (2016), although additional guidance will be provided during Phase 2 and throughout the FOAK design. AR 50-7 can be found at: https://armypubs.army.mil/epubs/DR_pubs/DR_a/pdf/web/r50-7_Web_FINAL.pdf.
Awarded vendors will be given opportunities to provide feedback on gaps in Army regulatory processes as additional regulatory guidance is provided. Additional regulatory requirements, such as transportation of nuclear material on public highways, should be addressed by Vendors during their proposals.
Reviews and implementation during the MPP prototype development process will include an integrated and phased approach to compliance with planning and design, planning and construction, architecture and engineering, building construction, environmental, operating, safety and physical/cyber protection, emergency response planning, deconstruction, and spent fuel management requirements.
A successful MPP prototype will provide a sound and demonstrated technological solution for commercial operations. A successful prototype will complete fuel load and testing phases and will be permitted by the Army Regulator to begin normal operations. The OTA prototype will transition to unrestricted operations as a COCO MPP with a Power Purchase Agreement (PPA), production OTA, or other Federal Acquisition Regulation (FAR) based contract.
Desired Solution Features
Desired solution features include the following attributes and capabilities:
Incorporates nuclear fuel that is enriched to 20% or less U-235 and that is legal for defense purposes. The fuel must be qualified, available, and fabricated on a timeline that will meet program timelines.
Defense-purpose feedstock may be made available as Government Furnished Equipment (GFE) for FOAK and SOAK MPPs through an Army fuel allocation process. If feedstock is provided as GFE, vendors will be responsible for transportation, blending, and fabrication of the fuel.
Vendors should address the implications of a) the Government not providing feedstock as GFE, b) of the Government providing feedstock as GFE for only the first fueling, and c) the Government providing feedstock as GFE for the operational life of the MPP.
Capable of producing electrical power in the range of kW-level up to 20MWe (up to 60 MWth). Capable of local control and dispatch and integrated to the greatest extent practicable into existing infrastructure, operations centers (if applicable), workflows, and operations and maintenance systems.
Capable of startup/shutdown and monitoring operations both with and without commercial power availability (both black start and grid-connected start capability).
Capable of MPP operations with a commercial power connection, and an alternative credited independent power source as a backup.
The MPP should be operated only from the control room located within the Army installation (remote or wireless operation is not allowed).
MPPs with remote maintenance and diagnostics capabilities that comply with relevant cybersecurity U.S. Government standards, e.g., NIST 800-171 Rev. 2 for Federal Contractors, may be considered.
The MPP control room must be designed to accommodate two operators, with space for an additional person, at a minimum.
The MPP design should include passive safety features to the extent practical to ensure MPP key safety functions are satisfied under all conditions, states, and modes.
Radiation exposure at the MPP site boundary should not exceed the limits provided in 10 CFR 20 during routine operations. Proposals must sufficiently account for relevant factors, including sky shine, emissions from activated site materials, and surrounding buildings at various elevations around the site boundary.
The MPP design must address Natural Hazard Phenomena, including seismic loads, external floods, and other potential hazards.
The MPP design must have clearly articulated systems and safety case approaches, including an initial set of proposed design criteria and design safety strategy.
Vendor strategy and capability to continuously provide full power supply for up to 30 years, including operations, maintenance, sustainment, and refueling activities.
There are no restrictions on the proposed strategy to achieve 30-years of continuous power (e.g., refueling or ‘replaceable’ modules to maintain continuity of operations).
The overall lifecycle strategy of the MPP by the Vendor will be evaluated and must include associated costs/risks with the proposed strategy for long-term operations.
Non-core irradiated material should be removed or qualified for unrestricted release within 2 years upon completion or termination of the power production contract. An initial irradiated material disposal plan, along with an associated finance structure, must be approved by the Army before design permitting.
Irradiated core material should be removed from the site notionally within 5 years of completion or termination of the power production contract, or as otherwise agreed upon by the Army. An initial core decommissioning plan, along with an associated finance structure, must be approved by the Army before MPP operations are permitted.
A target site area should be sized appropriately for FOAK (and SOAK if co-located) to ensure compliance with Federal radiation limits in 10 CFR 20 and the anticipated Seismic Design Category. Selected Vendors will be paired with an installation post-OTA award.
Reasonable and appropriate safety, physical, cyber, and safeguards measures should be implemented in the design consistent with best practices. Army-specific requirements will be provided to vendors invited to participate in Phase 2 Pitches.
In addition to the above desired solution features, solutions must address the aspects below:
A nuclear supply chain for nuclear-grade equipment that is clearly identified and credibly available to supply equipment to meet the notional timeline. The nuclear supply chain identified must meet defense-purpose limitations; any part of the nuclear supply chain reliant on international sources must be identified and mitigated with a plan approved by the Army.
Technology Readiness Level (TRL) and Manufacturing Readiness Level (MRL) for equipment included in the design. The TRL and MRL readiness levels will be evaluated in depth during Phase 2 Pitches.
Identified gaps in available Computational analytical tools, Codes, or Standards accepted for nuclear use. Identified analytical tools, Codes, or Standards for which the design will operate outside the approved range
(e.g., the MPP operates at a higher temperature than existing foundational data).
Identified gaps in available material performance data for safety or reliability-related equipment under anticipated operating conditions.
Plans and approaches to move from FOAK to SOAK, to Nth-of-a-Kind development and production. Plans to commercialize or develop commercial versions of proposed MPP prototype designs.
Long-term plans for fuel acquisition and manufacturing, including the status of negotiations or agreements with miners, enrichers and/or fabricators.
Are there any additional benefits I would receive?
Beyond direct prototype funding, awardees gain substantial strategic advantages:
Government Validation & National Credibility
Winning a DIU/Army nuclear award signals unmatched credibility in defense nuclear innovation. This accelerates alignment with primes, utilities, and capital markets.
Path to Long-Term, Non-Dilutive Revenue
Successful prototypes can transition into 30-year Power Purchase Agreements, production OTAs, or FAR contracts, representing massive long-term revenue potential.
Increased Market Visibility
Awardees gain visibility across DoD, DOE, and national energy/security communities—often resulting in media coverage and faster customer traction.
Supply Chain & Regulatory Acceleration
Participation provides exposure to Army regulators, national labs, nuclear fuel providers, and defense-focused supply chain partners—accelerating commercialization beyond the defense market.
Higher Exit and Valuation Potential
Nondilutive support for FOAK/SOAK nuclear builds significantly increases company valuation, technical defensibility, and acquisition potential for defense, energy, and infrastructure buyers.
What is the timeline to apply and when would I receive funding?
Solution Brief Due: December 15, 2025
DIU Review: ~30 days for down-select
Phase 2 Pitch: Invitation-only, early 2026
Full Proposal (Phase 3): Following successful pitch
Prototype Awards: Rolling upon approval and funding availability
FOAK Operation Goal: Before end of 2030
SOAK Development: Begins near completion of FOAK design
Where does this funding come from?
Project Janus is funded through the U.S. Army and executed under the Defense Innovation Unit's Commercial Solutions Opening (CSO) process. Awards are made using Other Transaction Agreements (OTAs) under 10 U.S.C. § 4022 (formerly § 2371b).
Who is eligible to apply?
U.S. and foreign-owned commercial companies
Companies proposing fission-based microreactor designs
Teams including reactor designers, fabricators, integrators, fuel cycle partners
Vendors able to provide private financial contributions (projects relying solely on government funds are not eligible)
Vendors able to comply with Section 889 and Army nuclear regulatory requirements
Multiple submissions and teaming arrangements are allowed.
What companies and projects are likely to win?
Competitive applicants will:
Demonstrate credible, deployable microreactor designs at TRL/MRL levels suitable for FOAK prototyping
Present a robust plan for 30 years of operations, including refueling or replaceable module strategies
Show credible nuclear supply chain access for fuel, components, and safety-critical systems
Provide a realistic path from FOAK → SOAK → Nth-of-a-kind commercialization
Demonstrate ability to meet Army regulatory requirements under AR 50-7
Provide private cost share or financial contributions, as required in Phase 2
Address cybersecurity, safety, passive safety features, and natural hazard requirements
Show strong corporate viability and commercial market strategy (a key DIU evaluation factor)
Are there any restrictions I should know about?
Remote or wireless operation of the MPP is not allowed; control room must be on-installation
Vendors may not contact Army installations
All proposals must be unclassified; CUI is not allowed
Foreign-owned firms must be able to secure necessary clearances
Vendors must address implications of fuel as GFE vs. vendor-supplied
Submissions must comply with Army radiation exposure limits and 10 CFR 20
Private financing participation is required to advance to Phase 2 and Phase 3
How long will it take me to prepare an application?
For a first-time applicant, preparing a competitive solutions brief will take 50-75 hours in total.
How can BW&CO help?
Our team specializes in complex federal R&D proposals and can:
Triple your likelihood of success through proven strategy and insider-aligned proposal development
Reduce your time spent on the proposal by 50–80%, letting your team focus on technology and operations
Ensure you are targeting the best opportunity for your project and positioning your company for long-term growth.
How much would BW&CO Charge?
Our full service support is available for the Solution Brief for $5000. Pitch & Full proposal quoted upon invitation.
Fractional support is $300 per hour.
For startups, we offer a discounted rate of $250 per hour to make top-tier grant consulting more accessible while maintaining the same level of strategic guidance and proposal quality.
Additional Resources
View the Solicitation Here.