The International Thermonuclear Experimental Reactor (ITER), under construction in southern France, has received significant media and Internet attention in the past decade. Most news articles and Web sites that are intended for lay audiences have published inaccurate information about ITER's purpose and design objectives. The primary sources for that information are the ITER organization headquarters and some of its national affiliated domestic agencies.
The main inaccuracies that have been communicated are that the ITER reactor as a whole (not just the plasma) is designed to a) produce significantly more power than it will consume, b) demonstrate a thermal power output 10 times greater than the reactor's power input, and c) produce 500 MW of thermal power from only 50 MW of power to operate the reactor.
In fact, only the plasma is designed to produce 10 times more thermal power than the 50 MW of thermal power injected into it. The ITER reactor as a whole (not just the plasma) is a) designed to produce slightly more power than it will consume, b) expected to produce a thermal power output 1.6 times greater than the reactor's power input, and c) designed to produce 200 MW of net thermal power. The reactor will require 300 MW of electrical power to operate.
A full review of the technical details of ITER power is presented in a separate report, "The ITER Power Amplification Myth"; however, a quick summary is useful.
Key Technical Facts About ITER Power
- ITER is designed to produce fusion products: neutrons and alpha particles. These particles will be measured by their thermal energy.
- ITER is designed to achieve a gross thermal output of 500 megawatts. ITER is not designed to convert this thermal power to electricity.
- ITER is designed to consume, and will require, 150 megawatts of electrical power, which will be used to inject 50 megawatts of heating power into the reaction chamber.
- ITER is also designed to consume, and will require, an additional 150 megawatts of electrical power to operate the machine.
- The planned total power consumption required to produce the 500 MW thermal power output for ITER is 300 MW of electricity during peak plasma output and 400 MW, momentarily, to get the reaction started.
- If the gross thermal output of 500 MW is compared with the minimum electrical input of 300 MW, the power amplification, or reactor gain, will be 1.6.
- With the gross thermal output of ITER at 500 MW, the maximum net output will be 200 MW, though this does not compare like terms. If the thermal output were converted to electricity, the net electrical power output would be negative 100 MW.
- The 300 MW value has not been published by the ITER organization. Only an ambiguous range of values, "110 MW up to 620 MW," has been published by the organization.
- In January 2017, after officials from ITER received multiple requests for the minimum required electrical power inputs, the officials failed to provide that information.
- The required electrical input values were obtained from three fusion experts, independently, representing some of the most prestigious fusion research institutions in the world.
- New Energy Times published the 300 MW value on Oct. 6, 2017. Thereafter, major fusion organizations, including ITER headquarters, ITER India, ITER Russia, EUROfusion, and the U.S. Department of Energy's Princeton Plasma Physics Laboratory, began correcting some of their false and misleading public statements.
- JET, the most successful fusion reactor in history, consumed 700 MW of electrical input power in its best experiment, on Oct. 31, 1997. The thermal power injected into the reaction chamber was 24 MW. The emitted thermal output power was 16 MW. It emitted only 2 percent of the power needed to reach reactor breakeven. Stated another way, the best fusion reactor output-to-input power ratio has been 2 percent.
Examples of People and Organizations That Have Been Misled
Atkins Company Web site: "ITER will produce 500MW of power for 50MW input - current record is 16MW." (Archive copy)
Air Liquide Web site: "[The ITER] project takes on the scientific and technical challenge of demonstrating that a fusion power plant could potentially generate 10 times more energy than it consumes." (Archive copy)
Malcolm Brown, New York Times, Dec. 10, 1996: "If successful, the reactor would ignite a fusion reaction and
produce up to 1.5 billion watts of power, demonstrating the feasibility of exploiting
hydrogen fusion for large-scale power generation." [Later redesigned for a target of 500 MW gross thermal output.]
Charles Seife and Peter Hadfield, New Scientist, Oct. 17, 1998: [Graph showing fusion reactor power output compared to light bulb, house, and power plant.]
Source: New Scientist, Oct. 17, 1998
Eugenie Samuel, New Scientist, July 11, 2001: "The goal of fusion research is a reactor that produces much more energy than the large
amounts needed to run it. The experimental tokamaks that exist around the world, such as the
Joint European Torus (JET) reactor at Culham near Oxford, have to date not progressed far
beyond the break-even point."
U.S. White House Press Release, Jan. 30, 2003: "If successful, ITER would create the first fusion device capable of producing thermal energy comparable
to the output of a power plant, making commercially viable fusion power available as soon as 2050."
Robert Stern, New York Times, Jan. 31, 2003: "ITER would provide a record 500 megawatts of fusion power for at least 500 seconds, a little more than eight minutes, during each experiment. That would meet the power needs of about 140,000 homes."
U.K. Parliamentary Office of Science and Technology, 2003: "Breakeven: when the total output power equals the
total input power. The ratio of these two quantities is
known as ‘Q’. Breakeven was demonstrated at the JET
experiment in the UK in 1997."
Elizabeth Clements, Fermi News, May 9, 2003: "If successful, ITER would produce 500 megawatts of fusion power for 500 seconds or longer ... the Tokamak Fusion Test Reactor at the Princeton Plasma Physics Laboratory, one of ITER’s predecessors that shut down in 1997, produced a maximum of 11 megawatts for only one-third of a second ... ITER would be the first magnetic confinement fusion experiment to produce burning plasma. The reaction would produce ten times the amount of external power injected into it."
Craig Freudenrich, Ph.D., How Stuff Works, Aug. 11, 2005: "The power needed to start the fusion reaction will be about 70 megawatts, but the power yield from the reaction will be about 500 megawatts."
Hamish Johnston, Physics World, Nov. 21, 2006: "It is hoped that ITER will produce 500 MW of power to demonstrate that it is feasible to generate power from fusion."
Andrew Orlowski, The Register, Oct. 22, 2008: "ITER is designed to produce 500MW for 300 to 500 seconds with an input of 50MW."
Nadia Ramlagan, APS News, November 2008: "ITER will use strong magnetic fields ... producing nearly 500 million watts of power. ... ITER will fuse deuterium and tritium together to form helium and a neutron, while releasing 10 times the amount of energy originally needed to make the nuclei fuse. ... [ITER] will be the first fusion reactor to create significantly more energy than it uses."
Ian Sample, The Guardian, Jan. 29, 2009: "In 1991, scientists at JET became the first in the world to produce energy from a deuterium/tritium plasma. While JET generated 16 MW of power, ITER is designed to produce some 500 MW in 400-second bursts."
Phys Org, June 18, 2009: "ITER is designed to produce 500 megawatts of power for extended periods, 10 times the energy needed to keep the energy-generating plasma − a form of radioactive gas − at extremely high temperatures."
This is technically correct but misleading. Phys Org did not inform readers of the true power requirements for the reactor, or explain that the objective is plasma gain rather than reactor gain.
Charles Seife, Sun in a Bottle, Oct. 27, 2009: "JET got 6 watts out for every 10 it put in. It was a record, and a remarkable achievement, but a net loss of 40 percent of energy is not the hallmark of a great power plant."
European Commission Press Release, May 5, 2010: "ITER will be capable of generating 500 million watts (MW) of fusion power." (Archive Copy)
Roger Highfield, Valerie Jamieson, Neil Calder and Robert Arnoux, New Scientist, Oct. 9, 2009: "In JET, TFTR, and JT-60, scientists have approached the long-sought 'break-even point,' where a device releases as much energy as is required to produce fusion. ITER's objective is to go much further and release 10 times as much energy as it will use to initiate the fusion reaction. For 50 MW of input power, ITER will generate 500 MW of output power."
The first sentence is in error; fusion reactors have never sought breakeven for the devices, only the plasma. The second sentence is accurate. The third sentence is wrong as it depicts the intended gain for the reactor rather than the plasma.
The first two authors of the article were New Scientist editors. The third author was the head of public relations for ITER, the fourth author was a staff member of the ITER public relations team.
Geoff Brumfiel, Scientific American, June 2012: "It will generate around 500 megawatts of power, 10 times the energy needed to run it."
Gaia Vince, BBC, Aug. 13, 2012: "The plan is to use 50 megawatts (in heating the plasma and cooling the reactor), and get 500 MW out ... The JET experiment in the UK, hasn't even managed to break even, energy-wise. Its best ever result, in 1997, achieved a 16 MW output with a 25 MW input."
Stephen Harris, The Engineer, April 25, 2013: "The experimental ITER reactor will produce around 500 MW of power." (Archive Copy)
Anthony King/Euroscientist, June 17, 2013: "ITER itself aims to show the feasibility of producing 500 megawatts, with an input of 50."
Raffi Khatchadourian, New Yorker, March 3, 2014: "[ITER will] produce ten times the energy fired into the plasma, at half a gigawatt."
This is technically correct but misleading. Khatchadourian did not inform readers of the true power requirements for the reactor, or explain that the objective is plasma gain rather than reactor gain.
Steve Connor, The Independent, April 27, 2013: "For every 50 megawatts of electricity it uses, it should generate up to 500 MW of power output in the form of heat."
Ethan Siegel, Forbes, Aug. 27, 2015: "The breakeven energy point in nuclear fusion [is] where we get out as much energy as we put in. … The reality is we’ve moved ever closer to the breakeven point."
This is misleading. Siegel did not inform readers that the current objective is plasma breakeven rather than reactor breakeven.
Alok Jha, The Guardian, Jan. 25, 2015: "[ITER's] design is a scaled-up version of JET, and the scientists here want to produce 500 megawatts of power, 10 times its predicted input."
Daniel Clery, Science, Nov. 19, 2015: "The ITER project aims to show that nuclear fusion — the power source of the sun and stars — is technically feasible as a source of energy. Despite more than 60 years of work, researchers have failed to achieve a fusion reaction that produces more energy than it consumes. ITER … is the biggest attempt so far and is predicted to produce at least 500 megawatts of power from a 50 megawatt input."
Will Mumford, SBS, Dec. 6, 2015: "In 1997, the Joint European Torus (JET) reactor produced a record 16 megawatts of fusion power; however, it took 24 megawatts of input power to create − a net loss. If successful, ITER will produce 500 megawatts of power for 50 megawatts of input power, a tenfold return."
Nathaniel Scharping, Discover, March 23, 2016: "ITER is projected to produce 500 MW of power with an input of 50 MW, … enough energy to power roughly 50,000 households."
Keith Wagstaff, Motherboard, May 3, 2016: "When completed, ITER is expected to create 10 times the energy that is required to produce and heat its plasma."
Davide Castelvecchi and Jeff Tollefson, Nature, May 26, 2016: "[ITER] is predicted to produce about 500 megawatts of electricity. "
Dave Loschiavo, Ars Technica, July 3, 2016: "[ITER] is projected to produce 500 MW of fusion energy while consuming 50MW to heat the hydrogen."
This is technically correct but misleading. Loschiavo did not inform readers of the true power requirements for the reactor, or explain that the objective is plasma gain rather than reactor gain.
Damian Carrington, The Guardian, Oct. 17, 2016: "ITER should be completed in 15-20 years and claims to deliver 500 MW of power, about the same as today’s large fission reactors."
Large fission reactors produce at least a net thermal output of 1,500 MW. ITER, by its design, will produce a net thermal output of 200 MW. Carrington was off by a factor of 7.5.
Damian Carrington, The Guardian, Dec. 2, 2016: "'We are convinced we can deliver hundreds of megawatts through ITER,’ up to 10 times more energy than is put in, says David Campbell."
Dec. 16, 2016, Luca Comisso, a post-doctoral researcher at Princeton University, contacted New Energy Times about a recent paper that he and his colleagues published:
LC: Although it may come across as unadulterated self-promotion, we truly believe that [our] work is potentially very significant in answering questions that have puzzled the astrophysical and fusion communities for decades. Hence, I have taken the liberty of reaching out to you to highlight our article.
SK: How would you explain to my readers what is significant and interesting about your work?
LC: The new results allow us to predict the behavior of the instability (called plasmoid instability), which has never been possible before, bringing us a step closer to controlled thermonuclear fusion.
SK: How close are we now to controlled thermonuclear fusion as an energy source?
LC: If the government decides that it is something in which they truly want to invest money, then we are pretty close, no more than 15 years, I think.
SK: In terms of net output of Watts or Joules, how close are we to controlled thermonuclear fusion as a power or energy source?
LC: ITER will produce 500 MW of fusion power starting from about 2025.
SK: How much total input power will the entire reactor require to produce that 500 MW?
LC: One tenth, i.e., 50 MW.
SK: Can you double-check your answer: How much total input power will the entire reactor require to produce that 500 MW?
LC: As I told you, only 50 MW.
Henry Fountain, New York Times, March 27, 2017: "ITER will benefit from its larger size and will produce about 10 times more power than it consumes."
Fraser Cain, Universe Today Web site, May 28, 2017: "If all goes well, ITER will have a ratio of 10. In other words, for every 10 MW of energy pumped in, it’ll generate 100 MW of usable power."
Jing Cao, Bloomberg, June 29, 2017: "[ITER’s] developers say it’ll produce 500 megawatts of power, using 50 megawatts to get the reaction going. That output could power a city of 375,000 homes."
Edwin Cartlidge, Nature, July 6, 2017: "ITER [will] generate electricity only in bursts of a few minutes." [Krivit posted comment, Nature corrected article, Nature removed Krivit comment] (Archive copy)
Edwin Cartlidge, BBC News, July 11, 2017: "[ITER] is designed to generate 10 times the power that it consumes."
Jason Socrates Bardi, Inside Science (American Institute of Physics), July 17, 2017: "The goal of ITER is to prove it’s possible to produce a net gain of energy. That means it will produce more power than it takes to make it. It will produce 500 megawatts of output power but only use 50 megawatts of input power."
S.A. Mathieson, The Register, Sept. 25, 2017: "[JET] set a record, producing 16MW of fusion power from a total input power of 24 MW. ITER, however, is a scaled-up version of JET currently under construction in the south of France planned to open in 2025 – a fusion reactor that aims to use 50 MW to generate 500 MW."
European Parliament Briefing, Sept. 2017: "While JET has produced a quantity of 16 MW of fusion power from a total input power of 24 MW (i.e., 0.67 MW of output per MW of input, or Q=0.67), ITER is designed to produce 500 MW of fusion power from 50 MW of input power (Q=10), or a tenfold return on energy." (Version 1, Archive Copy)
While JET has produced a quantity of 16 MW of fusion power from a total input power of 24 MW (i.e. 0.67 MW of output per MW of input, or Q=0.67), ITER is designed to produce 500 MW of output thermal power compared to 50 MW of input thermal power required to heat the plasma, which means an amplification factor of Q=10. (Version 2, Archive Copy)
European Parliament Document "The Impact of Brexit on the EU Energy System" (November 2017): "ITER is designed to produce 500 MW of fusion power from 50 MW of input power, i.e., a tenfold return on energy." (Archive copy)
Peter Teffer, EUObserver, Nov. 15, 2017: "The current challenge is to prove that a fusion reactor can be built which produces more power than it consumes."
Mark Lapedus, Semiconductor Engineering, Dec. 5, 2017: "The world record for fusion power is held by JET, a European effort. In 1997, JET produced 16 MW of fusion power from a total input power of 24 MW, according to ITER. In comparison, ITER is designed to produce 500 MW of fusion power from 50 MW of input power."
Alan Boyle, Geekwire, Dec. 6, 2017: "ITER’s ambition is to demonstrate a sustained fusion reaction that produces a net gain in energy."
Frank Jordans, Associated Press, Dec. 6, 2017: "[ITER is] a vast international experiment designed to demonstrate that nuclear fusion can be a viable source of energy. ... Scientists hope it will demonstrate that such a fusion reactor can produce more energy than it consumes."
Hannah Osborne, Newsweek, Dec. 6, 2017: "[ITER] would prove that fusion energy on a commercial scale is a possibility."
AP/Daily Mail, Dec. 6, 2017: "[ITER] is designed to show a fusion reactor can produce more energy than it consumes."
General Atomics, Dec. 6, 2017: "[ITER is] a project to prove that fusion power can be produced on a commercial scale and is sustainable." (Archive Copy)
Agencia EFE, Dec. 6, 2017: "ITER, the giant experimental machine that wants to demonstrate the viability of fusion energy as an alternative to fossil [fuels], ..."
Charles Q. Choi, Live Science, Dec. 7, 2017: "Its goal? To fuse hydrogen atoms and generate 10 times more power than goes into it. By the 2030s, ... the ITER tokamak should generate 500 megawatts of power."
Anmar Frangoul, Yahoo, Dec. 7, 2017: "[ITER is] a vast project to prove that fusion power is sustainable and can be generated on a commercial scale."
Charlie Wood, Christian Science Monitor, Dec. 11, 2017: "If successful, the colossal International Thermonuclear Experimental Reactor (ITER) will produce 10 times as much energy as it takes to run."
World Nuclear News, Dec. 11, 2017: "[ITER] is a major international project to build a 500MW tokamak fusion device (requiring an input of 50 MW) designed to prove the feasibility of fusion as a large-scale and carbon-free source of energy."
Natasha Romanzoti, Hypescience, Dec. 11, 2017: "So far, no one has built a fusion reactor that could supply a small town, a state or country. ITER is the hope to change that."
Veronique Le Billon, Les Echos, Dec. 12, 2017: "The goal of the 'big machine': to produce 500 megawatts with 50 megawatts of initial power."
This is technically correct but misleading. Le Billon did not inform readers of the true power requirements for the reactor, or explain that the objective is plasma gain rather than reactor gain.
Sputnik News, Dec. 12, 2017: "ITER project scientists calculate that their working experimental generator will generate about 500 megawatts of energy, five times the amount it consumes through its operation."
Lea Udov, Stakrog, Dec. 13, 2017: "The purpose of [ITER] is to build the largest experimental fusion reactor, in which, by means of fusion, they would generate 10 times as much energy as the reactor [uses]."
RIA, Dec. 13, 2017: "It is assumed that in the operating mode the installation will give 500 megawatts of energy. This is five times more than it consumes."
Patrick J. Kiger, How Stuff Works, Dec. 19, 2017: "But so far, [experimental tokamaks have] required more energy to operate than the fusion generates. But ITER hopes to overcome that. … ITER will use 50 megawatts of power input to generate 500 megawatts of fusion energy, in the form of heat."
Christa Marshall, E&E News, Dec. 21, 2017: "The international demonstration is aiming to generate about 10 times its input power."
Christa Marshall, Science, Dec. 21, 2017: "The international demonstration is aiming to generate about 10 times its input power."
Dom Galeon, Futurism, Dec. 30, 2017: "Best of all, the ITER tokamak has been designed to 'produce 500 MW of fusion power (Q≥10) from 50 MW of heating input power.'"
This is technically correct but misleading. Galeon, quoting directly from the ITER Web site, did not inform readers of the true power requirements for the reactor, or explain that the objective is plasma gain rather than reactor gain.
John Russell, VOA, Dec. 31, 2017: "The director of the ITER project says the facility is 50 percent complete and on track to produce low-cost energy."
Publico, Jan. 2, 2018: "500 megawatts of thermal power will be produced."
This is technically correct but misleading. The author did not inform readers that 300 megawatts of electricity will be consumed.
Muhammad Huzaifa Ali, The Nation - Pakistan, Jan. 8, 2018: "ITER ... will be able to produce 500 MW for up to 1,000 seconds with an input of only 50 MW."
Atul Pant, Institute for Defence Studies and Analyses, Jan. 10, 2018: "In all the experimentation conducted to date, it has not proved possible to obtain a higher output of fusion energy than the input energy. The best output to input energy ratio has been 65 percent."
This is misleading. Pant did not inform readers that the 65 percent value applied to plasma gain rather than reactor gain.
John Draper, Peerasit Kamnuansilpa, The Nation-Thailand Portal, Jan. 12, 2018: "Sometime after 2035, ITER is expected to produce 500 MW of fusion energy for 50 MW of input energy."
European Commission, Feb. 16, 2018: "ITER will be the first experiment to produce significant quantities of fusion energy, considerably more than required to operate the machine." (Archive copy)
Brittany Crocker, USA Today/Knox News, Feb. 15, 2018: "ITER is an international endeavor to build a reactor that produces much more energy than it uses."
Maria Temming, Science News, Feb. 17, 2018: "ITER in France is an international effort to build the first magnetic fusion reactor that pumps out more energy than it consumes."
Timothy Gardner, Reuters, March 6, 2018: "An international project to build a nuclear fusion reactor in France that would start generating electricity in 17 years will face delays if Trump administration cuts are not reversed in a few months, the head of the venture said on Tuesday. ... [ITER is] a nuclear fusion reactor in France that would start generating electricity in 17 years."
Reuters/Japan Times, March 6, 2018: "An international project to build a nuclear fusion reactor in France that would start generating electricity in 17 years will face delays if U.S. cuts are not reversed in a few months, the head of the venture said on Tuesday. ... [ITER] would generate electricity from a process similar to the fusion that powers the sun."
Editors/The Guardian, March 12, 2018: "JET hasn’t even managed to break even, energy-wise. Its best ever result, in 1997, remains the gold standard for fusion power – but it achieved just 16 MW of output for 25 MW of input."
Éanna Kelly/Science Business, March 15, 2018: "When completed, ITER will theoretically produce 10 times as much energy as it needs to run. It will be a 'massive, safe, clean, and predictable energy source for hundreds of thousands of years,' said Bigot. 'If we succeed - and we will - the breakthrough will be so large.'”
Samuel Sheppard/The Boar, March 28, 2018: "ITER promises to create a fusion reactor that can generate 10 times more energy than is put in."
Geert De Clercq/Reuters, April 13, 2018: "[ITER,] a prototype fusion reactor to generate electricity in a process similar
to the nuclear fusion that powers the sun."
World Nuclear News, April 19, 2018: "Iter is a major international project to build a 500MW tokamak fusion device (requiring an input of 50MW) designed to prove the feasibility of fusion as a large-scale and carbon-free source of energy."
Richard L. Hudson/Science Business, May 2, 2018: "ITER aims to switch on in 2025, and generate power by 2035."
Matteo Barbarino/IAEA, May 11, 2018: "[ITER] is expected to demonstrate by the late 2030s that fusion can be used to generate net energy, i.e. produce more energy than supplied to it to feed the reactor."
Katherine Bourzac/C&EN, Aug. 6, 2018: "By 2035, ITER will use 50 MW of input power to produce 500 MW of fusion power."
Sean O’Neill quoting Melanie Windridge/New Scientist, Sept. 15, 2018: "[ITER is] aiming to get about 10 times more energy out of the fusion reaction than they put in. That will prove fusion energy is possible."