Commercial timeline of fusion power

On 10 May 2023, Helion Energy said Microsoft would buy power from Helion’s first fusion plant, and the plant was aimed to be online in 2028 after a ramp of one year. This is the only dated purchase of fusion power on the record. The plant named in that deal has no facility page of its own.

The May 2023 purchase

The figure stored on the deal is 50 megawatts. The notice says “50 MW or greater”, and Constellation is the firm named to sell the power. It is marked binding on a reported remark by David Kirtley, Helion’s chief executive, which describes a binding agreement that carries financial penalties whose size is not stated.

Helion’s own announcement does not set those penalties out, and the terms have not been shown. The contract is not in the record. The company says it aims to take power straight from the expanding plasma, as that plasma pushes back on the magnetic field, with no steam turbine in the path.

Polaris is the Helion machine on this path. The record says it has been running since the end of 2024, on Helion’s word. A 2022 survey by the International Atomic Energy Agency had it down as planned. No figure for power sent out is stored for it. Engineering gain means power sent out, divided by the power a plant draws to run, and the definition says no fusion device has made electricity yet.

The plants named for a grid

Six plants on the record are typed as power reactors. Each of the six is still a plan. A date in the table is the day a name or a site was stated, the day a purchase was announced, or a year the operator aims at. Megawatts are written MW in the table.

Plant	Operator	Place	Electricity on record	Date on record
Helion’s first plant	Helion Energy	No facility record	50 MW or greater, after a one-year ramp	Announced 10 May 2023, online 2028
Da Vinci	TAE Technologies	No site stored	None stored	Named 17 November 2025
Stellaris	Proxima Fusion	Germany, site not fixed	None stored	A comment on 8 July 2026
ARC	Commonwealth Fusion Systems	Chesterfield County, Virginia	About 400 MW to the grid	Early 2030s, a target
STEP	STEP	West Burton, Nottinghamshire	None stored	First operations 2040, a target
Infinity Two	Type One Energy	Clinton, Tennessee	400 MW to the grid	No date stored
EU-DEMO	None stored	No site stored	300 to 500 MW net	No date stored

A name given in November 2025

On 17 November 2025, TAE Technologies said it could move directly into work on its first fusion power plant, and it named that plant Da Vinci, after dropping the Copernicus device from its roadmap. The record holds no site for it. No year of operation is tied to the name.

The same November 2025 release talks about a hydrogen-boron plant design, and it aims that design at commercial fusion in the early 2030s. Hydrogen-boron fuel means hydrogen nuclei fused with boron. That fuel and that year are not tied to the name Da Vinci.

Da Vinci is filed as a field-reversed configuration. That is a plasma ring which makes its own magnetic cage. The research machine the record places ahead of Da Vinci is Norm, which TAE says is running now and is also being upgraded.

A conditional site in July 2026

On 8 July 2026 the Max Planck Institute for Plasma Physics said Stellaris could be built where the former Gundremmingen nuclear power plant once stood, in Bavaria. The record leaves the site blank and stores only Germany.

Stellaris is Proxima Fusion’s idea for a first plant of the stellarator type. A stellarator holds the hot fuel with metal coils that are bent into a twist, so that no current has to be pushed through the fuel to keep it in place. Alpha is the test machine meant to come before that plant, and it is planned near the Institute, in the town of Garching. Neither the company page nor the institute note gives Alpha a start year.

Bull Run, and a plant with no year

Infinity Two is the stellarator power plant Type One Energy plans at Bull Run, a Tennessee Valley Authority site in Clinton, Tennessee. The firm states a deuterium-tritium fuel, which is two heavy forms of hydrogen. It pairs 800 MW of fusion power, the rate at which the reactions would release energy, with 400 MW sent out to the grid after the plant has fed itself.

No year is stored for Infinity Two. Infinity One is the machine Type One describes for engineering checks and for training, at Bull Run near Oak Ridge, and the completion target on it is 2029. The page never says construction has begun.

About 400 megawatts in Virginia

Commonwealth Fusion Systems says it will pay for the first ARC plant, and that it will build the plant and run it as the owner, at the Fall Line Fusion Power Station in Chesterfield County, Virginia, near Richmond. The firm says the plant arrives in the early 2030s. It would then put about 400 megawatts on the grid. The year given is the firm’s own target.

ARC is filed as a tokamak machine. A tokamak is a ring of hot fuel held in place by strong magnets and also by a current that is run through the fuel itself. SPARC, the machine before ARC, is being built in Devens, Massachusetts. Its aim is more fusion power out than heating power put in. Shots already measured on other machines are listed in the fusion milestones guide.

First operations aimed at 2040

STEP means Spherical Tokamak for Energy Production. It is the UK programme’s prototype plant, and it is planned for West Burton in Nottinghamshire on the site of a former coal-fired power station. The programme aims at first operations in 2040.

A spherical tokamak is that ring pulled into a rounder shape. No power rating is stored for STEP. The pages say the programme is at present paid for entirely by government, and that a firm set up by government, UK Fusion Energy, will lead the alliance that delivers the plant.

Those pages cite £1.3 billion for the next stage, and they name ILIOS, a joint venture of Kier and Nuvia, as construction partner. The record shows no date for a construction start.

300 to 500 megawatts, and no site

EUROfusion asks that EU-DEMO send 300 to 500 megawatts of net power to the grid. Net means power left after the plant feeds itself. The same line also asks for a closed tritium fuel cycle, tritium being the heavy radioactive form of hydrogen used with deuterium, and the record never says how that cycle would be closed.

The status note calls this conceptual design. No operator is stored, and no site is stored. EU-DEMO is the plant set down to follow ITER, and ITER is still being built at Saint-Paul-lez-Durance in the south of France.