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FusionBenchmark

Magnetic vs inertial confinement

The two dominant routes to fusion. One holds a thin plasma steady for seconds; the other crushes a fuel capsule in nanoseconds. They are not measured with the same yardstick, which is where most confusion starts.

Magnetic confinement

Holding a hot plasma away from material walls using magnetic fields, sustained for seconds to steady-state rather than the nanosecond pulses of inertial confinement. The open problem shared by every configuration below is exhausting the plasma's heat and helium ash without eroding the wall that must survive it for years, not seconds.

127 devices · 35 organisations · 454 measurements

Inertial confinement

Compressing fuel so fast that its own inertia holds it together long enough to burn: nanoseconds, not seconds. Every ICF approach shares the same open problem beyond ignition itself: repeating a shot several times a second at low enough cost per shot to run a power plant, which no driver has yet demonstrated.

8 devices · 14 organisations · 32 measurements

Differences

Magnetic vs inertial confinement compared
  Magnetic confinement Inertial confinement
How confinement works Magnetic fields hold a low-density plasma continuously. A driver implodes a fuel capsule; its own inertia confines it for nanoseconds.
Density and duration Low density, long duration — seconds to minutes. Extreme density, durations measured in nanoseconds.
How gain is quoted Plasma gain: fusion power over external heating power coupled into the plasma. Target gain: fusion yield over laser energy delivered to the target. These denominators are not interchangeable.
What has been achieved JET released 69.26 MJ in a single pulse; no device has exceeded plasma gain of 1. NIF exceeded target gain 1 in December 2022, reaching 1.5.
The comparison trap A magnetic device quoting plasma gain is counting heating power only. An inertial device quoting target gain excludes the laser system’s own vast inefficiency. Same shot, wall-plug gain below 0.008.

Devices

Magnetic confinement 127

Inertial confinement 8

Organisations

Magnetic confinement 35

Commonwealth Fusion SystemsEnergy Matter Conversion CorporationEnergy SingularityENN Science and Technology DevelopmentFirefly FusionGauss FusionGeneral AtomicsHelical FusionHelion EnergyHHMAX-EnergyInstitute of Plasma Physics, Chinese Academy of SciencesITER OrganizationKorea Institute of Fusion EnergyLINEA InnovationsMaritime FusionMax Planck Institute for Plasma PhysicsMIT Plasma Science and Fusion CenterNational Institute for Fusion ScienceNational Nuclear Center of the Republic of KazakhstanNovatron Fusion GroupNT-TaoOpenStar TechnologiesPranos FusionProxima FusionRealta FusionRenaissance FusionStartorus FusionStellarex EnergySTEPTAE TechnologiesTerra FusionThea EnergyTokamak EnergyType One EnergyUK Atomic Energy Authority

Inertial confinement 14

Anubal FusionBlue Laser FusionChina Academy of Engineering PhysicsEX-FusionFocused EnergyGenFHB11 EnergyInertiaInnoven EnergyLawrence Livermore National LaboratoryLongview Fusion Energy SystemsMarvel FusionUnited States Naval Research LaboratoryXcimer Energy