P-01
FRC equilibrium
Tuszewski and Steinhauer set out the equilibrium and confinement physics of high-beta field-reversed configurations.
Tuszewski, Nuclear Fusion 28 (1988) · Steinhauer, Physics of Plasmas 18 (2011)
Public technical case
Can the full pulse return net electrical work and repeat?
Published experiments have formed, merged, and compressed FRC plasmas. Laurelin's proposed machine adds direct recovery and a protected electrical measurement to that sequence.
FIG. 01 · CONCEPT STUDY
§I · Public record
The cited experiments report the mechanisms separately.
They cover FRC equilibrium and formation, merging with magnetic compression, and direct conversion. No cited experiment joins them in the complete Laurelin cycle.
P-02
FRC formation
Published experiments have formed hot, stable field-reversed configurations.
Gota et al., Nuclear Fusion 59 (2019)
P-03
Merging + compression
Published experiments have merged two colliding FRCs and produced high-temperature plasma through merging and compression.
Slough, Votroubek & Pihl, Nuclear Fusion 51 (2011)
P-04
Direct conversion
Published theory and experiments establish direct conversion in principle. No cited paper reports its integration with a compact pulsed FRC at engineering relevance.
Barr & Moir (1976) · Takeno et al. (2000, 2019, 2023)
§II · The open test
The test is a repeatable shot with metered electrical output.
Laurelin's design puts the published mechanisms in one test. A passing record shows useful peak conditions within hardware limits and metered electrical work at the protected boundary, reproduced at engineering-relevant cadence.
Published record
FRC formationTwo-FRC mergingMagnetic compressionDirect conversion
Open operating record
One repeatable pulse with metered electrical work§III · Proposed pulse sequence
The first three plasma steps have published precedents.
Direct recovery from the pulsed FRC and repetition of the complete sequence remain open integration work.
- 01Published precedent
Form
Form the two FRC plasmas used in the shot.
- 02Published precedent
Merge
Merge the two plasmas into one FRC.
- 03Published precedent
Compress
Raise the merged plasma's density and temperature with magnetic compression.
- 04Open integration
Recover + meter
Return electrical work through the proposed direct-conversion channel and meter it at the protected boundary.
- 05Open integration
Repeat
Reset the machine and reproduce the full record at an engineering-relevant cadence.
§IV · Compactness
Why the proposed machine is compact and pulsed.
High beta is the physical basis for compactness. At fixed magnetic field and plasma content, the FRC equilibrium permits a smaller device volume. Pulsed operation puts energy input and returned work on the same shot record, including the cadence between shots.
HIGH-BETA EQUILIBRIUM
High beta permits a smaller device volume.
An FRC is a compact toroid with no central rod. Its high-beta equilibrium permits high plasma pressure relative to the magnetic pressure used to confine it.
BOUNDED PACKAGE
The compactness claim includes recovery and service systems.
Recovery, shielding, instrumentation, and service interfaces must close as one bounded object. Moving those burdens into the host site would be deferred bulk, not compactness.
§V · Fuel constraint
D-D reduces external fuel dependency and raises the confinement requirement.
The public brief puts the minimum Lawson-product requirement for D-D at roughly two orders of magnitude above D-T. The proposed machine must absorb that penalty in its per-pulse energy ledger.
Deuterium is the terminal fuel, so operation does not depend on an externally supplied strategic isotope inventory. The reaction branches still produce tritium, helium-3, and neutrons.
NET-ENERGY CONDITION · EACH PULSEηrec · Efus ≥ Edrv + Ppar / frep
§VI · Direct recovery
Each accepted shot needs an electrical record.
The pulse delivers energy on microsecond-to-millisecond timescales. Direct electromagnetic conversion addresses it in the same time domain. Thermal capture remains necessary for energy outside the direct channel.
Protected-boundary ledger
- Input
- Driver energy per pulse
- Output
- Returned electrical work
- Cadence
- Measured repetition rate
- Record
- Uncertainty + off-nominal behavior
§VII · Failure conditions
The integrated test has four failure conditions.
A strong plasma result cannot compensate for failure in repeatability, material survival, protected recovery, or package integration. Each condition needs its own record.
E-01
Repetition-rate stability
Can the high-β FRC equilibrium be reproduced at the repetition rate deployment economics require? The public record is still dominated by short-pulse, low-duty-cycle campaigns.
E-02
Materials qualification
The ²H–²H neutron spectrum sets the plasma-facing-material, activation, and service budgets. Closure requires a qualification record on the operating spectrum—not a claim that the spectrum has been designed away.
E-03
Protected recovery measurement
Direct conversion must become metered, protected, and repeatable at engineering relevance. Recovered electrical work is the evidence; inferred plasma energy is not the same measurement.
E-04
Container integration
The core envelope, adjacent balance of plant, service boundary, and regulatory surface must compose at operational scale. Packaging only matters if the deployment system closes around it.
Public sources
Read the public whitepaper.
It contains the full energy ledger and source list behind this page.