Petition to extend JET beyond 2023



Let's follow the science. We should inspect and refurbish JET in 2024, while building an international consortium to upgrade and operate it. Imagine what we could do with 10-20 MW of ECRH, a new divertor, a W wall, Boron and/or Lithium dropper!

Emilia Solano (Madrid, 2023-10-14)


Closing JET now is like decapitating fusion research in general. The effects will be felt for years to come, certainly now where ITER can make good use of JET results. I am confident that when the different parties sit around the table a solution can be found. Let us not repeat similar mistakes of the past, which afterwards were regretted bitterly.

Jozef Ongena (Brussels, 2023-10-14)


Magnetic fusion needs large operational machine(s) until ITER or other large facility becomes available.

Sergei Sharapov (Abingdon, 2023-10-15)


JET is unique, and there's still nothing comparable running anywhere in the world. It's a waste to dismantle it.

Ewa Pawelec (Opole, 2023-10-15)


Even this week, JET has demonstrated its value to help prepare for ITER. The delays to ITER motivate critical work to prepare its operating scenarios for more rapid progress to D-T operation. Ongoing JET exploitation would provide unique enabling research for this mission. (Signing in a personal capacity, not representative of my employer or program).

Richard Buttery (San Diego, 2023-10-15)


I feel very strong about the lack of logic from the scientific and technological standpoint of closing down Jet at this point in time when, among other reasons,
D-T experimental capability is most needed in the worldwide fusion community

Alfredo Portone (Barcelona , 2023-10-15)


JET has a unique potential and the ITER rebaselining calls for a supporting scientific and technical programme, that JET can address at a level which cannot be achieved neither on any other tokamak nor with any combination of tokamaks worldwide

Jérôme Pamela (Aix en Provence , 2023-10-15)


There is already a huge infra-structure in place that can serve as testbed for a variety of scientific and engineering goals for fusion reactor's research.

Ernesto Lerche (Brussels, 2023-10-15)


I'm signing because I feel that the full potential if JET is not yet exhausted with the experiments so far completed.

Henri Weisen (Bussigny, 2023-10-15)


The prioritisation of electron heating on ITER is putting in doubt many of the extrapolations from JET that the envisaged ITER scenarios are based on. Upgrading and operating JET comes at a relatively low cost compared to the capital value of the already existing machine.

Ephrem Delabie (WALLINGFORD, 2023-10-15)


JET is the only tokamak which can operate in Deuterium Tritium for the foreseeable future. It remains the largest 14MeV neutron source, by a massive margin. These two attributes alone means that retaining JET is essential for the efficient progress towards the goal of electricity production from Nuclear Fusion.

Morten Lennholm (Oxford, 2023-10-15)


I am signing because JET provides a unique test bed for magnetic fusion research. The combination of an established device operation, research team, and diagnostic set means that JET is optimized to allow progress. I only wish that we had kept TFTR longer and I hope that the same mistake is not made with JET.

Jim Strachan (Bensalem, 2023-10-15)


This would allow to keep critically needed expertise alive for fusion and transfer it to the next generation of engineers, technicians and scientists. It also would be a time-saving and thus cost-saving operation for next step devices (ITER, STEP, etc) by providing a test facility to advance research in a range of topics.

Pierre Dumortier (Ganshoren, 2023-10-16)


JET is still the best tokamak in the world contributing to our path to Fusion. Private-public partnership in Fusion development would be strongly supported by experimental results of JET.

Mikhail Gryaznevich (Abingdon, 2023-10-16)


I am working at JET for the last 20 years and I witness the remarkable, unique results of our machine in different areas including fast particle physics, transport and confinement, MHD stability, plasma-wall interaction, diagnostics development for fusion plasmas. Apart from the obvious importance of JET results for ITER these results provide the key contributions to the burning plasma physics of future power plant and reactor operation (scenario development in DT plasmas, optimisation of the fusion power, safety and control of the DT operation). Presently, there is no other machine which could address these issues. The closure of such important large-scale project without providing at the same time the continuity at the equivalent or better level is a big step back in fusion research, the loss of expertise, the loss of trained team. I would like to ask our colleagues to support the JET operation at the international level and I am confident that the international fusion community will have many excising JET results in future!

Irina Voitsekhovitch (Abingdon, 2023-10-16)


There is very little experience of operation of DT plasmas, which is key tp preparing for fusion power production and JET is the only realistic device available for many years to work in this area.

Kenneth Young (Princeton, 2023-10-16)


I'm signing because of JET's size and capabilities, including the only tokamak in the world that can operate D-T plasmas. Wither ITER's start date uncertain, JET's shutdown would serious impact progress toward the realization of fusion energy.

Robert Kaita (Manalapan, 2023-10-16)


I believe fulfilling this petition will be of a benefit for the fusion community

Mikhail Maslov (Abingdon, 2023-10-16)


I adhere to the text of the petition

Philippe Jacquet (ABINGDON, 2023-10-16)


I would like to see JET continuing to produce unique fusion relevant results

Ionut Jepu (Didcot, 2023-10-16)


JET is still the flagship of world fusion and the only machine capable of running D-T. Refurbishing it's systems and re-tiling the divertor and wall more in line with current ITER expectations along with adding ECRH is only logical. Furthermore, I can think of a few diagnostic improvements.

Andrew Meigs (Abingdon, 2023-10-16)


I strongly agree with the case being made in this petition. JET is still the most relevant magnetic confinement fusion device in the world, and fills a critical need in providing a reactor-relevant and DT compatible scientific and technological integration and demonstration platform for informing ITER and next-step devices. The JET infrastructure and capabilities are unparalleled in magnetic fusion research.

Bart Lomanowski (Oak Ridge, 2023-10-16)


Demolishing JET is the elimation of the only chance to develop high performace and disruption stable low recycling regime for tokamak fusion. But I do not see any value in continiation the ssme high recycling research on this unique facility for the real fusion. Other macines can replace JET in the conventinal aproach, which has disruptions as unavoidable intrinsic property.

Leonid Zakharov (Princeton, 2023-10-16)


Results from JET experiments will still be very important for the development of a fusion reactor.

Ernesto Mazzucato (Princeton, 2023-10-16)


I believe JET is well positioned for at least the next two years to provide critical data to support research on DT nuclear fusion. JET is and can be very productive in providing this critical data.

Gary Taylor (New Egypt, 2023-10-16)


Research in fusion is important

Robert Budny (Princeton, 2023-10-16)




Katriya Sabin (Abingdon, 2023-10-16)


I have put a lot of energy and time to become a competent member of the ICRH group on JET. I do not want it to end, I think JET has so much more to offer and I want to be part of its potential future.



I'm signing this petition because JET is Europe's largest, well functioning, and most successful tokamak fusion experiment. Its closure would substantially reduce Europe's competitiveness in fusion energy research and most likely lead to a loss of experienced physicists and engineers, especially since the dates for the operation of ITER are still uncertain.

Manfred Bitter (Princeton, 2023-10-16)


JET is the only fusion device capable of operating with tritium. It is also one of the few devices on which new scientists can be trained who will have the requisite relevant experience to ensure ITER's successful operation in the coming years.

Dennis Mueller (Hopewell, NJ, 2023-10-16)


I want to keep my job

Gasken Stunner (London, 2023-10-16)


JET provides extremely useful research facilities for future developments

Alan Frener (Salisbury , 2023-10-16)


This is about the future of the planet and our children

Monica Roberts (LONDON, 2023-10-16)


I would like to help stop the place from closing down.

Paige Morgan (London , 2023-10-16)


JET is the leading magnetic fusion facility worldwide with a uniquely creative scientific team. It can make new critical contributions to the magnetic fusion mission.

Boris Breizman (Austin, 2023-10-16)


JET is currently the largest tokamak in the world. Today it was announced during the IAEA conference that ITER will have some extra delays. This makes that the shutdown of JET would mean that for a longer time we cannot perform experiments/increase our knowledge about what is happening in large tokamaks.

Dieter Boeyaert (Madison, 2023-10-16)


I am sure the JET is unique facility to explore ITER scenarios and critical issues before its first plasma. Scientific community needs the JET expeiments to test reactor physics in expectancy of ITER operation.

Sergei Lebedev (St Petersburg, 2023-10-16)


As a NBH operator and technician of 40 plus years I have been proud to participate in experiments that only JET with its unique capabilities could perform. As the only experiment able to get close to the operation of ITER it is needed to continue operations until ITER is ready for operations.

David Ewers (Great Yarmouth, 2023-10-16)


As a world record holder for the most fusion output of any fusion device, and since ITER has continued to suffer delays, I feel it is important we keep JET operational. Doing so is certain to deepen our understanding of plasma behavior in fusion relevant regimes.

Michael Gerard (Madison, 2023-10-16)


I support the text of this petition.
JET will offer unique capabilities for many years to come. It is needed to insure the success of other programs including ITER.

Francois Waelbroeck (Austin, 2023-10-16)


JET has a still alor to contribute to science and fusion. It is producing much meaningful physics than other currently running fusion machines

Ridhima Sharma (Didcot, 2023-10-16)


I have done research on fusion for more than 10 years. JET experiments have always been fruitful and beneficial to our community, please keep it going.

Boonyarit Chatthong (Songkhla, 2023-10-16)


I'm signing because JET is one of the fascinating facilities and most appropriate to test ITER scinario.

Kunihiro Ogawa (Toki, 2023-10-17)


JET still has a, significant play to role as the only truly nuclear fusion facility in operation. Many technologies associated with fusion power plan development, primarily related to the nuclear aspect, can still be tested on JET before commercial deployment.

Martin Nieto-Perez (State College, 2023-10-17)


JET still has. A lot to offer to fusion research

George Sips (San diego, 2023-10-17)


I'm convinced in continuing importance of JET, especially in light of possible upgrades such as W first wall, for studies of ITER and reactor relevant physics, in particular plasma -walk interaction.

Yevhen Zayachuk (Oxford, 2023-10-17)


A credible way forward to accelerate fusion, derisk ITER, and keep EU competences

Volker Naulin (Birkerød, 2023-10-17)


We need answers to our significant power problems. The research into fusion is not complete yet.

Ashley Walters (Oxford, 2023-10-17)


JET was the largest experiment and it will be important during the first phases of iter operations.

Tomas Odstrcil (San Diego, 2023-10-17)


I agree with the proposals

Tom Gedling (Oxford, 2023-10-17)


Fusion will be the future human mankind

Nico Pupeter (Wuppertal, 2023-10-17)


I am signing Petition to extend JET beyond 2023 because
I completely agree with the supporters of the petition, there will be no JET - there will be big problems with the launch of ITER,
Sincerely, Gunta Kizane

Gunta Kizane (Riga, 2023-10-17)


JET's capabilities are not covered by any other machine. We need it.

Cedric Tsui (San Diego, 2023-10-17)


The life of JET should be extended beyond 2023 as it would be very useful to support ITER. The proposition to install a Tungsten (W) wall and 10+ MW of ECRH, a boron dropper and to internationalize JET, such that the funding for operations could be secured in the coming years.

Radhika Mishra (Warsaw, 2023-10-17)


World’s more relevant experiment demonstrating highest performance. The most cost-effective way to advance in fusion research and mitigate risks for ITER.

Eduardo de la Cal (Madrid, 2023-10-17)


Having been working at/for JET for 20+ years, I am one of the remaining JET Session Leaders and know the machine very well and also recognise its potential to resolve important outstanding questions on the step ladder to a fusion reactor. I would also like to add to this petition a (relatively straightforward) suggestion to expand the JET pellet system to increase the number of pellet injectors to have several separate injectors for fuelling and ELM pacing, aiming to replicate ITER's pellet setup.

Christian Perez von Thun (Warsaw, 2023-10-17)


- As ITER demonstrates, a lot of the cost a machine is in its construction, and in the construction of the infrastructure and in attracting personnel. JET already exists, the personnel is there as well as the buildings to house them. Aligning a program with what it can still do - mitigating risks of major failures - would be beneficial. High-risk operation should likely be avoided to avoid unnecessary extra costs, but that is a question of properly defining boundaries of operation.
- Funding is likely a sore item. Different funding could be attracted. JET does not need to be a EUROfusion or UKAEA machine.
- JET has a number of essential systems that needed upgrading while the actual machine itself is robust. Recent investments made (NBI upgrade, cryostat) have cured some of these so purely economically it seems to make full sense to keep the machine in operation a bit longer as a "return on investment". Together with the refurbished NBI system things seems ready for some more decent action and recent campaigns have been plagued less with "out" time than various campaigns before ... This seems a less logical time to stop the machine's operation than as has been the case in the past.
- Future machines will be operating for long times and evidence so far suggests coping with impurities will be a major challenge in them. As JET is equipped with a metal wall it could provide useful information on how to cope with impurities. The machine also has a set of diagnostics allowing to perform such studies, and tools to mitigate deleterious effects (power, pellet launcher,...). Ensuring long-term viability of systems is one of the challenges the fusion community faces.
- JET has a powerful NBI system which provides the main heating source for high performance discharges; NBI was upgraded some years ago and made the recent records possible. Pushing the machine to full performance might not be optimal but performing experiments at a somewhat more modest power level is likely possible without necessitating extra costs.
- JET has a very versatile ICRH system, which has proven to be essential for setting the new records because of its capability to deposit power where it is needed: in/near the core. ICRH has also performed a lot of tasks besides heating (it has e.g. been an essential tool for transport studies because of its capacity to deposit power locally) and could continue to do so. JET has been a testbed for scenarios all along its lifetime; the 3-ion scheme is likely the most recent example.
- JET has a wealth of diagnostics and the personnel to man them (locally or via EUROfusion)
- Gradually more detailed modelling is being done. JET can be an invaluable for providing evidence for a large-size machine. Dynamics in a large-size machine is different from that in smaller devices: the power densities are lower but also the volume-to-surface ratio is. JET is likely the closest machine we have to ITER ...
- Last but not least: JET is capable and permitted to run DT experiments if ever extra experiments would be wanted/needed to provide further insights for the sake of ITER.

Dirk Van Eester (Sint-Katherina-Lombeek, 2023-10-17)


given the change in timeline for ITER, and the re-baselining of its research plan, closing JET now will leave a huge gap in the world fusion capabilities.

Fernanda Rimini (Oxford, 2023-10-17)


I agree with the proposals

Teddy CRACIUNESCU (Bucharest, 2023-10-17)


I believe that many preparatory experiments for ITER can still be done on JET.

Niels Horsten (Leuven, 2023-10-17)


JET is a unique facility, which has obtained umatched results until very recently (last week...) This device, a beautiful illustration of what Europeans can achieve when they unite, has been an attraction pole for the fusion community as a whole since it began operation. In view of new delays and fresh decisions impacting ITER, JET should be upgraded to keep answering relevant questions, and continue to play its central role in fusion research.

Remi Dumont (Saint-Paul-lez-Durance, 2023-10-17)


It is too early.
I cannot understand "destroying" such a tool.

Michel Jadoul (Limal, 2023-10-17)


I must concur with our learned international friends who have already made excellent arguments.

Michael Fitzgerald (Abingdon, 2023-10-17)


JET's operation and performance have shown that it still has enormous potential in thermonuclear research. It is a complete, ready-to-use machine with which new records can be set and breakthroughs made.

Maryna Chernyshova (Warsaw, 2023-10-17)


I'm signing because de Jef needs to be able to do his tricks at JET and secure future energy supply

Stijn Van Opstal (Antwerpen, 2023-10-17)


I believe this petition is very important

Annelies Mermans (Antwerp, 2023-10-17)


JEt is an incredible machine that needs maintenance and expertise to keep producing incredible results.

Bruno Viola (Oxford, 2023-10-17)


It would incredibly damaging to fusion research to close the JET Facilities. Let's not repeat the mistkes of the past in closing important facilities that have turned out to be irreplaceable.

Bruno Coppi (Boston, 2023-10-17)


JET is the only device before ITER that can study Tritium and DT plasmas. This support is extremely important for ITER.

Andres Cathey (Garching bei München, 2023-10-17)


I ha personally worked on JETwhich has been a successful scientific enterprise for over 40 years, going well beyond its design target performance and expected lifetime ( see design report R 14) .It is still in condition to lead worldwide fusion research and reach higher goals, at only running costs. These are high, but worthwhile meeting up, by the international scientific institutions so far involved.

Enzo Lazzaro (Cormano, 2023-10-17)


ITER's announcement of a transition to a tungsten wall means it would be extremely helpful to collect a new dataset on JET with tungsten walls.

James Paterson (Oxford, 2023-10-17)


I'm an early career fusion researcher (graduate engineer 2023 cohort) and started doing shifts operating JET last month. If the machine is retired now, 40 years of experience operating JET will be lost as the older generation retire and my generation and those after me will have to wait decades for a machine with similar capabilities. It could also be used to test synergistic effects on breeding blankets as there is no "test rig" for combining magnetic fields, high temperatures and neutron irradiation over a large volume in particular.

Clara Cottet (Oxford, 2023-10-17)


Fusion research needs JET to answer critical physics questions and train the next generation of fusion scientists, particularly with the delays to ITER.

James Oliver (Culham, 2023-10-17)


It's still too early to close such a world-unique device! There is still work to do to prepare operational scenarios for a more rapid progress to D-T operation, and JET is still the only tokamak that can ensure a successful implementation of this work. So it is quite irrational to close JET now when there is still so much to do, to be checked before any other facility is ready to take over this work.

Ewa Kowalska-Strzęciwilk (Warsaw, 2023-10-17)


I strongly agree

Raju Daniel (Gandhinagar , 2023-10-17)


JET is a unique facility that enables cutting-edge fusion experimental programs. It probably should be more open for private companies since they grow fast and are in need of some advanced and diverse testing platforms and science support.

Georgy Subbotin (Luxemburg, 2023-10-17)


We need JET to continue to help in the new ITER wall configuration

Daniel Alegre Castro (Madrid, 2023-10-17)


JET is indeed a unique facility. Unless HL-3 gets its licence to operate with D-T, there will be no experiment with D-T between now and ITER. I. Chapman mentioned at the FEC, that they are seeking new international cooperations. JET would be a perfect basis.

Jean-Marie Noterdaeme (Aachen, 2023-10-17)


Everybody's talking about reducing our CO2 emissions, and nuclear fusion would just be a cornerstone for our future energy production. So we must relentlessly continue the research in this domain

Didier VANDER LINDEN (Sint-Stevens-Woluwe, 2023-10-17)


With the new challenges for fusion we need an experienced facility to move foreward and also keep people trained

Jan Coenen (Jülich, 2023-10-17)


I want jet exp to continue

Jose Rueda (Seville, 2023-10-17)


Best for world MFE program

Patrick Diamond (San Diego, 2023-10-17)


I expect many more important advances, physics insights and contributions to ITER can be made by large machines like JET and JT-60SA and their excellent teans.

Andreas Bierwage (Naka, 2023-10-17)


It's the best facility in the world

Minsheng LIU (Beijing, 2023-10-17)


Closing JET is a big mistake

Hongjuan Sun (Oxford , 2023-10-17)


JET has still potential to fill a decade gap until next D-T capable machines will be up and running but it require substantial investment (1£b program) and time(3-5 years) for a major refurbishment/upgrades programs of few years at least.
JET has unique ability to be used as a test bench for materials (eg.14MeV neutrons) as well as a platform for teaching next generation of operators.

Alexandru Boboc (Abingdon, 2023-10-17)


Experiments on JET are important for ITER

Pengfei Zheng (Chengdu, 2023-10-17)


A full tungsten wall may also increase the likelihood of sudden disruptions due to tungsten injections. This should be added to the list of experimental open questions that could be addressed by a refurbished/upgraded JET.

Robert Granetz (Cambridge, 2023-10-17)


JET shutting down would leave a hole in the fusion ecosystem that would not be filled for years to come.

Grant Rutherford (Cambridge, 2023-10-17)


It is fundamental to have a large machine in operation until ITER is working.

Fernando Nabais (Lisboa, 2023-10-17)


Relevance of the project towards the ITER machine

Pietro Testoni (Barcelona, 2023-10-17)


As said JET is unique, close JET damages the chances of achieving commercial success

Frederick Hurd (Cholsey , 2023-10-17)


I’m signing because there is still much to do with Jet itself and its data.

Alexei Zhurba (Barcelona, 2023-10-17)


JET is able to provide actual scientific research

Mikhail Drabinskiy (Moscow, 2023-10-17)


JET is needed until ITER is ready to keep expertise on several areas (DT not the least) and to advance physics understanding.

Antti Salmi (Espoo, 2023-10-17)


JET provides vital reaearch within the field of fusion research. The need for a facility capable of handling T and DT plasmas is crucial for our understanding of burning plasmas, and is very much needed with ITER's latest delays.

Phillip Bonofiglo (Princeton, 2023-10-17)


JET is currently the largest and most important Tokamak Fusion experiment in the world capable of achieving Nuclear Fusion. Closing JET down will leave a period of around 10 years before ITER physics operations will begin in earnest. In addition to providing an important testing ground for Fusion-relevant physics, JET provides an indispensable resource for training engineers and physicists in the operation and maintenance of Fusion-relevant tokamaks.

lynton appel (Oxford, 2023-10-17)


We still need JET

Gerardo Giruzzi (Aix-en-Provence, 2023-10-17)


JET is an extremely important part of the world fusion program

Michael Kotschenreuther (Austin, 2023-10-17)


JET is an unique machine with great potential for DT operation in support of ITER and future fusion development, and should be kept operating if possible

Di Hu (Beijing, 2023-10-17)


I am totally convinced that JET can contribute towards ITER, SPARC and DEMO operations.

At JET, uniquely in the world, researchers can be trained to operate a burning plasma experiment (session leader, diagnostics, ....). If it closes, there will be an inevitable gap and many researchers will leave fusion research.

We need to prepare the young generation towards the next step devices and JET is the suitable test bed experiment.

Lidia Piron (Padova , 2023-10-17)


JET is a unique facility to prepare ITER operation.

Giovanni Piazza (Sant Cugat del Valles, 2023-10-17)


This is a big ask, and almost certainly too late, but it needs to be made. I will be retiring in a few years, so although I have worked on JET for almost forty years I doubt this will make much difference to me personally.

Peter Card (Didcot, 2023-10-17)


Fusion energy needs JET research to continue, to mitigate further risks at ITER. It would be illogical to close it down at this stage.

Ajay Gandhi (Barcelona, 2023-10-17)


Electron heating of a large fusion plasma needs to be tested for ITER.

Marc Beurskens (Berlin, 2023-10-17)


JET is important facility in tokamak research.

Hong-sik Yun (Seoul, 2023-10-17)


It seems scientific madness to close JET while at its prime in exploiting unique capabilities so spectacularly for the advancement of MCF. JET's potential for future contributions that will be invaluable for MCF and ITER, is far from exhausted, and it will be some time before the machine is superseded. From a parochial UK perspective its untimely closure will resemble recent events at "Sycamore Gap".

Colin Roach (Abingdon, 2023-10-17)


I think the continued operation of an upgraded/refurbished JET should provide interesting new data for the effective operation of ITER.

David Coster (Garching, 2023-10-17)


JET is currently the only device that can carry out DT experiments, and its size is uniquely large, providing an irreplaceable platform for high-performance burning plasma.experiments which is crucial to ITER. Although other big machines like JT-60SA and SPARC are supposed to be built up soon, there is still a couple of years that these machines can operate to full parameters. Scientists will appreciate it very much if JET can run for a few more years before other big machines can take its place.

Yihang Chen (Chengdu, 2023-10-17)

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