Fusion: of 6 promised milestones none came on time; 4 have not been reached
- ITER: first plasma by 2019not yet
- ITER: first plasma by 2025not yet
- Laser ignition by 201210.2 years late
- 100 million degrees by 20183.2 years late
- SPARC: net energy by 2025not yet
- Helion: electricity by 2024not yet
Of 6 promised milestones none came on time; 4 have not been reached.
Ignition at the US laser facility came 10.2 years after the deadline. ITER’s first plasma was promised for 2019, then for 2025; now research operation is to start in 2034.
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Fusion is the energy that makes the Sun shine; on Earth people have tried to get it in tokamaks and laser facilities since the 1950s. Here are six promised milestones: state projects and private companies.
A row is one promise: who, what and by when. The question is whether at least half came true. Answer Yes or No, or just open the answer: each row gets its outcome and what actually came of it, the card a stamp counting those that came true. Quotes and links to the facts are below.
- Laser ignition by 2012 — U.S. Department of Energy (NNSA), 2011 years past the deadline
promised by 2012; happened 5 December 2022 (10.2 years late). Ignition at NIF was achieved on 5 December 2022, about 10 years after the end of FY2012.
- ITER: first plasma by 2019 — ITER Council, 2010 years past the deadline
promised by 2019; not happened by 11 October 2026. No first plasma; the 2024 baseline dropped that milestone altogether: start of research operation in 2034, deuterium-tritium in 2039.
ITER Organization, Proposed new baseline, press conference summary, 3 July 2024
- 100 million degrees by 2018 — Tokamak Energy, 2017 years past the deadline
promised by 2018; happened 10 March 2022 (3.2 years late). The company announced 100 million degrees in ST40 on 10 March 2022, about 3 years late.
Tokamak Energy, «Tokamak Energy moves closer to commercial fusion», 10 Mar 2022
- Helion: electricity by 2024 — Helion Energy, 2021 years past the deadline
promised by 2024; not happened by 11 October 2026. Polaris has run since late 2024, but Helion has not reported net electricity; in February 2026 it announced the first private deuterium-tritium fusion.
Helion Energy, «Helion achieves new fusion energy milestones», 13 Feb 2026
- ITER: first plasma by 2025 — ITER Council, 2016 years past the deadline
promised by 2025; not happened by 11 October 2026. No first plasma by the end of 2025; since October 2020 ITER has said the date was unachievable, and the 2024 baseline starts research operation in 2034.
ITER Organization, Proposed new baseline, press conference summary, 3 July 2024
- SPARC: net energy by 2025 — Commonwealth Fusion Systems, 2021 years past the deadline
promised by 2025; not happened by 11 October 2026. SPARC had not reached Q>1 by the end of 2025; the company now names 2027.
Promises: verbatim from the primary sources, ITER Council decisions, US Department of Energy budget documents, company statements. The date of the event is from a primary source, linked on the back for each row. The delay is counted from the end of the promised period: «by 2020» from the end of 2020, «in October» from the end of October. Outcome: «came true» — the promised number reached by the deadline («about» within 5%), an event happened before the end of the year promised; «exceeded» — with room to spare; «nearly» — short by no more than 10%; «late» — reached, but after the deadline; «did not come true» — not reached; «came true, then undone» — reached, then reversed. The deadline is the end of the year named.
The milestones differ: first plasma is switching the machine on; ignition is a reaction giving more energy than went into the fuel; net energy, more than went into the plasma; electricity, power to the grid. Private companies name new dates: SPARC, 2027.
A question for this picture
Why has fusion energy been «thirty years away» for half a century?