TerraPower's Molten Salt Reactor with Internal Heat Exchangers
This patent describes a unique molten salt nuclear reactor design by TerraPower, featuring an open-topped vessel and integrated heat exchangers for efficient internal cooling and fuel circulation.
Original patent title: “Fast spectrum molten chloride test reactors”
This patent describes a unique molten salt nuclear reactor design by TerraPower, featuring an open-topped vessel and integrated heat exchangers for efficient internal cooling and fuel circulation. Granted to Terra Power in 2023 with 20 claims and 1 forward citation, and it is expected to expire in 2041.
Coverage
What does this patent actually cover?
This patent outlines a molten fuel salt nuclear reactor where the main vessel is open at the top but has no other openings, a design choice intended to simplify construction and enhance safety. Inside this vessel, a 'neutron reflector' surrounds the core where nuclear reactions occur. Above this core, several 'heat exchangers' are placed, acting like radiators to remove heat from the hot molten fuel salt. A 'flow guide assembly' with a 'draft tube' directs the hot fuel salt from the central core region, through the heat exchangers, and then down an 'annular downcomer duct' before it flows back into the central core region, creating a continuous cooling loop. For example, hot fuel salt from the core flows up, transfers its heat to a coolant in the shell-and-tube heat exchangers (ClaimclaimA numbered sentence at the end of a patent that legally defines what the inventor owns. The most important section.Read more → 5), then flows down the annular downcomer duct, and re-enters the core to be heated again.
The gap
What does this patent NOT cover?
- Molten salt reactors where the primary reactor vessel has openings or penetrations other than the top opening (ClaimclaimA numbered sentence at the end of a patent that legally defines what the inventor owns. The most important section.Read more → 1).
- Reactor designs where the heat exchangers are located outside the main reactor vessel (ClaimclaimA numbered sentence at the end of a patent that legally defines what the inventor owns. The most important section.Read more → 1).
- Circulation systems that do not use a 'draft tube' to separate the central reactor core volume from an 'annular downcomer duct' (ClaimclaimA numbered sentence at the end of a patent that legally defines what the inventor owns. The most important section.Read more → 1).
- Reactors that do not circulate fuel salt from the reactor core volume, through heat exchangers, into a downcomer duct, and then back into the reactor core volume (AbstractabstractA short summary at the front of the patent describing the invention. Not legally binding.Read more →).
These exclusions are unique to PatentBrief — derived from the actual claim language, not patent-office boilerplate.
Key facts
What made this novel
The truly novel aspect is the integrated design where the entire primary circulation path, including the heat exchangers, is contained within an open-topped vessel that has no other penetrations. This simplifies the vessel's construction and potentially enhances safety by minimizing potential leak points.
The Patent Drawing
Schematic visualization of the patent's claim structure. Hand-drawn diagrams in progress for each landmark patent.
Where you've seen this
Real-world examples
TerraPower's Molten Chloride Fast Reactor (MCFR) designs
Advanced nuclear reactor concepts
Next-generation nuclear power plant designs
Why it matters
The bigger picture
Molten salt reactors (MSRs) represent a significant area of innovation in advanced nuclear energy, promising enhanced safety features and more efficient fuel utilization. TerraPower, the assigneeassigneeThe entity that owns the patent — usually the inventor's employer or a company.Read more →, is a prominent developer in this field, with backing from Bill Gates. This patent contributes to the intellectual property foundation for developing modular, safer, and potentially more cost-effective nuclear power solutions.
Filed
July 28, 2021
Granted
August 15, 2023
Market context
Who's building on this
Companies in this space
TerraPower LLC, the assigneeassigneeThe entity that owns the patent — usually the inventor's employer or a company.Read more →, is actively developing molten salt reactor technologies, including the Molten Chloride Fast Reactor (MCFR), which this patent likely supports. Other companies like Kairos Power and Elysium Industries are also exploring advanced molten salt reactor designs and related technologies.
Market impact
This patent contributes to the ongoing development of advanced nuclear power, a sector aiming to provide carbon-free energy with improved safety and efficiency. It helps define the technological landscape for molten salt reactors, potentially influencing future reactor designs and deployment strategies by offering a unique approach to internal cooling and vessel integrity. This could enable more compact and modular reactor designs, impacting the future energy market.
Claim 1 — Plain English
What this patent covers
This patent outlines a molten fuel salt nuclear reactor where the main vessel is open at the top but has no other openings, a design choice intended to simplify construction and enhance safety. Inside this vessel, a 'neutron reflector' surrounds the core where nuclear reactions occur. Above this core, several 'heat exchangers' are placed, acting like radiators to remove heat from the hot molten fuel salt. A 'flow guide assembly' with a 'draft tube' directs the hot fuel salt from the central core region, through the heat exchangers, and then down an 'annular downcomer duct' before it flows back into the central core region, creating a continuous cooling loop. For example, hot fuel salt from the core flows up, transfers its heat to a coolant in the shell-and-tube heat exchangers (Claim 5), then flows down the annular downcomer duct, and re-enters the core to be heated again.
The clever bit
The truly novel aspect is the integrated design where the entire primary circulation path, including the heat exchangers, is contained within an open-topped vessel that has no other penetrations. This simplifies the vessel's construction and potentially enhances safety by minimizing potential leak points.
What it does not cover
- Molten salt reactors where the primary reactor vessel has openings or penetrations other than the top opening (Claim 1).
- Reactor designs where the heat exchangers are located outside the main reactor vessel (Claim 1).
- Circulation systems that do not use a 'draft tube' to separate the central reactor core volume from an 'annular downcomer duct' (Claim 1).
- Reactors that do not circulate fuel salt from the reactor core volume, through heat exchangers, into a downcomer duct, and then back into the reactor core volume (Abstract).
Patent timeline
Application submitted to the patent office
Application published, typically 18 months after filing
Patent officially issued
Patent enters public domain
PatentBrief Score
Impact Score
Early stage
Citation count
6/40
Early citations
Claim breadth
13/20
Broad claimsclaimsThe numbered statements at the end of a patent that legally define what the inventor owns.Read more →
Recency
20/20
Granted within 5 years
Assignee scale
0/20
Independent or smaller assigneeassigneeThe entity that owns the patent — usually the inventor's employer or a company.Read more →
PatentBrief Impact Score — based on citation count, claim breadth, recency, and assignee scale. Not a legal assessment.
Heuristic Value Estimate
What this patent might be worth
$88K – $281K
Midpoint $176K · 15.0 yr remaining · industry ×1.5
Heuristic only — blends forward/backward citation counts, claim scope, time remaining, litigation history, and CPC-derived industry baseline. Real valuations need a professional appraisal.
Claim text not yet imported for this patent
The original legal language
Original claims
20 claims as filed with the patent office.
Concepts involved
Citations
Patent lineage
Cite this patent
JR., A. T. C., Walter, D. J., Edwards, M. J., Ullah, N., Deleo, F., Wardle, K. E., Markham, G. T., & Roecker, J. A. (2023). TerraPower's Molten Salt Reactor with Internal Heat Exchangers (U.S. Patent No. 11,728,052). U.S. Patent and Trademark Office. https://patentbrief.org/patent/us/11728052/fast-spectrum-molten-chloride-test-reactors
Auto-generated from the patent record. Double-check author order and the issue date against the official USPTO document before submitting.
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Common Questions
Frequently Asked Questions
What does TerraPower's Molten Salt Reactor with Internal Heat Exchangers cover?
This patent describes a unique molten salt nuclear reactor design by TerraPower, featuring an open-topped vessel and integrated heat exchangers for efficient internal cooling and fuel circulation.
Who owns patent US 11728052?
Terra Power owns this patent, granted in 2023.
When does this patent expire?
This patent is expected to expire on July 28, 2041, when the invention enters the public domain.
What is patent US 11728052 cited by?
This patent has been cited by 1 later patents that build on its ideas.
What problem does this patent solve?
Molten salt reactors (MSRs) represent a significant area of innovation in advanced nuclear energy, promising enhanced safety features and more efficient fuel utilization. TerraPower, the assignee, is a prominent developer in this field, with backing from Bill Gates. This patent contributes to the intellectual property foundation for developing modular, safer, and potentially more cost-effective nuclear power solutions.
What does this patent NOT cover?
Molten salt reactors where the primary reactor vessel has openings or penetrations other than the top opening (Claim 1).
Patent monitoring