Overview
Los Alamos physicists achieved fusion ignition using a target that shouldn't have worked. On June 22, 2025, their THOR design—deliberately adding windows that leak crucial energy—generated 2.4 megajoules of fusion power at the National Ignition Facility. The shot created burning plasma, a self-sustaining reaction where fusion itself drives more fusion. It was ignition with a scientific instrument built in.
Three years ago, fusion ignition was a 60-year moonshot finally achieved. Today it's repeatable science. NIF has progressed from barely breaking even in December 2022 to generating 8.6 megajoules in April 2025—4.1 times the laser energy input. The windowed THOR achievement proves ignition is now robust enough to accommodate major design modifications, opening pathways to study weapons physics and materials under star-like conditions without underground nuclear tests.
Key Indicators
People Involved
Organizations Involved
The $3.5 billion facility fires 192 lasers at hydrogen fuel capsules to create conditions found in stars and nuclear weapons.
One of two U.S. labs responsible for nuclear weapons design and the science-based stockpile stewardship program.
Birthplace of the atomic bomb, now advancing fusion diagnostics and weapons science through novel target designs.
Timeline
-
DOE Releases Fusion Roadmap
PolicyDepartment of Energy announces strategy targeting commercial fusion power by mid-2030s.
-
Los Alamos Achieves Windowed Ignition
BreakthroughLANL's THOR design with diagnostic windows achieves 2.4 MJ ignition, proving robustness.
-
Record 8.6 MJ Yield Sets New Bar
RecordNIF achieves 8.6 MJ output from 2.08 MJ laser drive, yielding 4.1x gain.
-
Yield Doubles Input Energy
ProgressExperiment produces 5.2 MJ from 2.2 MJ laser energy, more than doubling input.
-
Second Ignition Exceeds First
ProgressNIF achieves 3.88 MJ from 2.05 MJ input, confirming ignition is repeatable.
-
Public Announcement of Ignition
AnnouncementEnergy Secretary Jennifer Granholm announces historic achievement to the world.
-
First Fusion Ignition in Laboratory History
BreakthroughNIF produces 3.15 MJ from 2.05 MJ laser input, achieving scientific breakeven for first time.
-
Major Breakthrough Shot
ProgressNIF achieves 1.3 MJ yield, 70% of laser input energy, 25 times previous record.
-
Ignition Campaign Falls Short
SetbackInitial campaign ends at 1/10 of conditions needed for ignition after two years of attempts.
-
NIF Becomes Operational
FacilityNational Ignition Facility fires all 192 laser beams for first time, delivering 1.098 megajoules.
Scenarios
Commercial Fusion Plants Operating by 2035
Discussed by: Department of Energy roadmap, Commonwealth Fusion Systems, 35 of 45 private fusion companies
The early 2030s become the transformation decade. Private companies like Commonwealth Fusion Systems and Helion Energy translate NIF's ignition physics into commercial reactor designs using different approaches—magnetic confinement tokamaks and pulsed non-ignition systems. Government and private investment exceeds $15 billion annually by 2030. First pilot plants demonstrate net electricity production by 2032. Commonwealth's Arc reactor in Virginia begins delivering 400 MW to the grid by 2034, with Microsoft and Google as anchor customers. By 2035, multiple facilities operate commercially, though fusion remains a small fraction of the energy mix.
China Dominates Fusion as U.S. Funding Stalls
Discussed by: Department of Energy assessments, Clean Air Task Force analysis of comparative investment
Chinese government funding continues at $3 billion annually while U.S. investment remains under $200 million. By 2030, China operates multiple tokamak facilities achieving higher performance than NIF. Chinese firms commercialize fusion power domestically by 2035 while U.S. companies struggle with insufficient capital. America retains scientific leadership through NIF but loses the commercial race. The fusion industry mirrors solar panel manufacturing—pioneered in the U.S., scaled and commercialized in China. By 2040, China exports fusion reactor technology globally while U.S. utilities buy Chinese designs.
Fusion Ignition Remains Laboratory Science
Discussed by: IEEE Spectrum analysis, fusion skeptics pointing to engineering challenges
NIF continues achieving higher yields in laboratory conditions but the path to commercial power remains blocked by fundamental engineering barriers. Laser inefficiency means NIF uses 300 MJ of electricity to produce 2 MJ of laser light yielding 8.6 MJ of fusion energy—still net negative overall. No one solves the repetition rate problem; NIF fires once per day while commercial plants need shots every second. Materials can't withstand sustained neutron bombardment. Tritium breeding proves impractical. By 2040, fusion remains a stockpile stewardship tool and physics research platform. Private companies quietly wind down after burning through investment.
Breakthrough Materials Enable Fusion Scaling
Discussed by: Materials science researchers, DOE Fusion Energy Sciences strategic planning
THOR windowed experiments accelerate materials discovery by providing sustained access to fusion-relevant radiation environments. By 2028, researchers identify new alloys and composites that survive neutron bombardment without degrading. These materials solve the first wall problem plaguing all fusion approaches. Simultaneously, AI-designed laser systems achieve 10x better efficiency. Companies retrofit NIF-style inertial confinement designs with new materials and efficient lasers. By 2033, the first net-positive fusion facility operates continuously. The materials breakthrough triggers an investment wave exceeding $50 billion. Fusion scales faster than predicted.
Historical Context
JET Tokamak Sets Fusion Record (1997-2024)
1997-2024What Happened
The Joint European Torus in the UK achieved 16 MW of fusion power in 1997, a record that stood for 25 years. JET used magnetic confinement in a doughnut-shaped tokamak, sustaining fusion reactions for seconds rather than NIF's nanosecond pulses. In its final experiments before decommissioning in 2024, JET produced 69.26 megajoules over six seconds from 0.21 milligrams of fuel.
Outcome
Short term: Demonstrated sustained fusion reactions were possible, validating tokamak approach for ITER.
Long term: Proved magnetic confinement could achieve significant fusion yields, though still below breakeven.
Why It's Relevant
JET's sustained burns contrast with NIF's instantaneous ignition, showing fusion has multiple viable paths with different trade-offs.
Manhattan Project and National Labs (1943-1945)
1943-1952What Happened
The U.S. established Los Alamos in 1943 to develop atomic weapons, achieving the first nuclear detonation in July 1945. After World War II ended, weapons laboratories pivoted to peacetime missions. Lawrence Livermore was founded in 1952 as a second nuclear design lab. Both facilities transitioned from building bombs to maintaining the arsenal without testing.
Outcome
Short term: Created institutional infrastructure for nuclear weapons development that won World War II.
Long term: National labs became centers for extreme physics research, eventually hosting fusion experiments like NIF.
Why It's Relevant
Today's fusion breakthroughs happen at labs built for weapons, using facilities designed to study nuclear detonations without testing.
U.S. Solar Industry Rise and Fall (1970s-2000s)
1973-2012What Happened
America led solar photovoltaic development through the 1970s oil shocks, with government funding and Bell Labs innovations. By the 1990s, U.S. companies dominated manufacturing. Then China entered with massive subsidies, scaling production beyond U.S. capacity. By 2012, Chinese firms produced solar panels at costs American manufacturers couldn't match, driving most U.S. companies bankrupt.
Outcome
Short term: U.S. lost manufacturing dominance but retained technology leadership through research.
Long term: China controls 80% of global solar manufacturing; U.S. became dependent on Chinese imports for renewable energy.
Why It's Relevant
Fusion risks the same trajectory—U.S. achieves scientific breakthrough but loses commercial race to countries that invest in scaling.