Thermonuclear Fusion

1. Thermonuclear Fusion Mapping a Controversy using Actor-Networks By Bryce C. Elder SCI 361U: Science: Power-Knowledge Portland State University Spring 2010 Original musical score composed by Bryce Elder

2. General Introduction For a number of decades, the possibility of finding virtually limitless or renewable energy sources has become increasingly attractive in light of sociopolitical climates. Considering population growth, and the human need for more and more energy every day, it behooves us to move forward with research designed to uncover alternatives to ever dwindling supply of fossil fuels.

3. General Introduction One possible alternative energy source which is currently being researched, is that of thermonuclear fusion. Currently, there are theoretically a handful of ways to produce conditions where nuclear fusion can occur, but for practical purposes, and in order to portray the levels of magnitude of the actor networks currently involved in the production of fusion devices, I will outline just a few of the facilities where these experiments are being done, and where science is currently “in the making”. This slideshow will serve to describe 2 competing approaches for the confinement of fusion energy which are being developed in tandem, which both seek to achieve a net energy gain through the fusion of atomic particles.

4. Introduction to Fusion Fusion is the process that powers the Sun. It is the energy that makes life on Earth possible. Unlike nuclear fission, which releases energy when a heavy atom splits into two lighter elements, fusion releases energy when the nuclei of two light atoms combine, such as when two hydrogen nuclei fuse to form a helium atomic nucleus. The Earth does not have the gravitational pressure of the Sun so plasma must be confined and heated to temperatures ten times higher than those in the Sun in order to get a sufficient number of fusion reactions. The approach to the confinement process is currently the leading edge of science in the making, and there are multiple actors currently experimenting in the field. Making fusion on Earth requires two heavier types (or isotopes) of hydrogen: deuterium - with a nucleus of one proton and one neutron (an atomic particle with similar mass to the proton but no electrical charge) and tritium (with one proton and two neutrons). When these two nuclei fuse together they produce a new helium nucleus (also known as an alpha particle) and a high-energy neutron. In a future fusion power plant, the energy of that neutron will be captured and used to heat steam to generate electricity as in a normal power station, while the electrically charged alpha particle will transfer its energy to the plasma, keeping it hot. Source: http://www.iter.org/

5. Introduction to Fusion • What makes fusion so important, and why should we care? • Fusion energy has the potential to provide a sustainable solution to global energy needs. In particular it can provide a continuous base load power supply which is sustainable, large-scale and environmentally responsible, using fuels that are universally available. • Limitless fuel - The raw fuels for fusion are water and lithium. There is around 0.033 grams of deuterium in every liter of water. Tritium is not found on Earth but can be easily made from lithium - an abundant metal found in batteries that power mobile phones and laptops. Tritium can be made in situ in a fusion reactor by using the neutron released by the fusion reaction. If the neutron is absorbed by a surrounding 'blanket' of lithium then tritium is produced. • Inherent safety - The volume of gas in a fusion reactor will always be low, at around 1 gram of fuel in 1000 cubic meters. Any problem will always cool the plasma and stop reactions - so a runaway situation is impossible. Also the raw fuels for the reactor (deuterium and lithium) are not radioactive. Tritium is mildly radioactive but will be produced and used within the reactor. Consequently, no transport of radioactive fuels will be needed for a fusion power plant - and even the worst possible case accidents would not require evacuation of neighboring populations. • Environmental impact - Fusion power will not create greenhouse gases, produce other harmful pollutants or result in long-lasting radioactive waste. Its fuel consumption will be extremely low. A 1000 megawatt electric fusion power station would consume 100 kg of deuterium and three tons of lithium a year to generate 7 billion kilowatt-hours of power. To do the same a coal-fired power station would need 1.5 million tons of coal. • The fusion fuels are not radioactive. The neutrons generated by fusion will interact with the materials close to the reactor, but careful choice of these materials will ensure that no long-term legacy of radioactive waste is produced by fusion power. • Source: http://www.iter.org/

6. Current Approaches: The central issue to the ability to control nuclear fusion lies in our ability to confine the massive quantities of heat and plasma which are required to produce fusion. There are currently two leading schools of thought regarding approaches to “confinement” Being (commercially) developed as we speak!

7. General Introduction Magnetic Devices: Notably the “ITER” project in Europe. The 'tokamak' concept of magnetic confinement, in which the plasma is contained in a doughnut-shaped vacuum vessel. The fuel - a mixture of Deuterium and Tritium, two isotopes of Hydrogen - is heated to temperatures in excess of 150 million°C, forming a hot plasma. Strong magnetic fields are used to keep the plasma away from the walls; these are produced by superconducting coils surrounding the vessel, and by an electrical current driven through the plasma. Source: http://www.iter.org/

8. The Tokamak

9. General Introduction Laser Inertial Confinement: National Ignition Facility USA 192 Intense laser beams, focused into a tiny gold cylinder called a hohlraum, will generate a "bath" of soft X-rays that will compress a tiny hollow shell filled with deuterium and tritium to 100 times the density of lead. In the resulting conditions – a temperature of more than 100 million degrees Celsius and pressures 100 billion times the Earth's atmosphere – the fuel core will ignite and thermonuclear burn will quickly spread through the compressed fuel, releasing ten to 100 times more energy than the amount deposited by the laser beams. In a fusion power plant, the heat from the fusion reaction is used to drive a steam-turbine generator to produce electricity. Source: https://lasers.llnl.gov/

10. The Hohlarum(inside the target chamber)

11. The Target Chamber

12. Perspective: Fusion History 1905 Einstein provided the first clues on how the Sun works in 1905 with his famous E=mc² equation derived from his special theory of relativity. This simple equation predicted that the conversion of a small amount of mass (m) could yield a very large amount of energy (E) with the conversion factor being the square of the speed of light (c = 3 x 108meters per second). 1920 The key experimental observation was made in 1920 by British chemist Francis William Aston who took precise measurements of the masses of atoms. He was then able to relate the process of atomic fusion to that which was taking place in our own Sun. Sir Arthur Eddington, a British astrophysicist then realized that by burning hydrogen into helium, the Sun would release about 0.7% of the mass into energy. 1939 German physicist Hans Bethe completed the picture with a quantitative theory explaining the generation of fusion energy in stars. Some early and unsuccessful experiments were conducted in the Cavendish laboratory in Cambridge, UK, during the 1930s, but it was only after World War Two and the development of nuclear fission weapons that interest in fusion, and nuclear technologies in general, increased 1950 The original large-scale experimental fusion device was built in the late 1940s and early 1950s at Harwell in the UK. The Zero Energy Toroidal Assembly (ZETA) worked from 1954 to 1958 showing initial promise and producing useful results for later devices. Source: wikipedia

13. Magnetic Devices Timeline 1946 Registration of the first patent related to a fusion reactor by the United Kingdom Atomic Energy Authority, the inventors being Sir George Paget Thomson and Moses Blackman,  1951 The U.S. fusion program began in 1951 when Lyman Spitzer began work on a stellarator under the code name Project Matterhorn. His work led to the creation of the Princeton Plasma Physics Laboratory, where magnetically confined plasmas are still studied. A new approach was outlined in the theoretical works fulfilled in 1950–1951 by I.E. Tamm and A.D. Sakharov in the Soviet Union, which first discussed a tokamak-like approach. 1956 At the Kurchatov Institute in Moscow Russian scientists construct the first tokamaks, the most successful being the T-3 1968 It’s larger version T-4, was tested in Novosibirsk, producing the first quasistationary thermonuclear fusion reaction ever. 1980’s In 1978 the European JET project was launched in Europe and came into operation in 1983, about the same time as the Tokamak Fusion Test Reactor (TFTR) in the USA. The Japanese tokamak JT-60 came online in 1985. 1990’s In 1991, JET produced for the first time in the world a significant amount of power (1.7 megawatts-MW) from controlled nuclear fusion. Subsequently, in 1993 TFTR produced 10 MW of power. The current world record for fusion power was regained by JET in 1997 when it hit 16 MW. Source: Wikipedia

14. Magnetic Devices Timeline Today Very large tokamaks like ITER are expected to pass several milestones toward commercial power production, including a burning plasma with long burn times, high power output, and online fueling. There are no guarantees that the project will be successful; previous generations of tokamak machines have uncovered new problems many times. But the entire field of high temperature plasmas is much better understood now than formerly, and there is considerable optimism that ITER will meet its goals. If successful, ITER would be followed by a "commercial demonstrator" system, similar in purpose to the very earliest power-producing fission reactors built in the era before wide-scale commercial deployment of larger machines started in the 1960s and 1970s. Even with these goals met, there are a number of major engineering problems remaining, notably finding suitable "low activity" materials for reactor construction, demonstrating secondary systems including practical tritium extraction, and building reactor designs that allow their reactor core to be removed when its materials becomes embrittled due to the neutron flux. Despite optimism dating back to the 1950s about the wide-scale harnessing of fusion power, there are still significant barriers standing between current scientific understanding and technological capabilities and the practical realization of fusion as an energy source. Research, while making steady progress, has also continually thrown up new difficulties. Therefore it remains unclear whether an economically viable fusion plant is possible. A 2006 editorial in New Scientist magazine opined that "if commercial fusion is viable, it may well be a century away." Interestingly, a pamphlet printed by General Atomics in 1970s stated that "By the year 2000, several commercial fusion reactors are expected to be on-line." Several fusion D-T burning tokamak test devices have been built (TFTR, JET), but these were not built to produce more thermal energy than electrical energy consumed. Despite research having started in the 1950s, no commercial fusion reactor is expected before 2050. The ITER project is currently leading the effort to commercialize fusion power. A paper published in January 2009 and part of the IAEA Fusion Conference Proceedings at Geneva last October claims that small 50 MW Tokamak style reactors are feasible. • Source: http://ec.europa.eu/index_en.htm

15. Laser Inertial Confinement Timeline 1962 First suggested by scientists at Lawrence Livermore National Laboratory, shortly after the invention of the laser itself, in 1960 1965 Low level research begins with low powered laser systems 1968 Philo T. Farnsworth, the inventor of the first all-electronic television system in 1927, patented his first Fusor design, a device that uses inertial electrostatic confinement. This system consists largely of two concentric spherical electrical grids inside a vacuum chamber into which a small amount of fusion fuel is introduced. Robert Hirsch designed a variant of the Farnsworth Fusor known as the Hirsch-Meeks fusor. This variant is a considerable improvement over the Farnsworth design, and is able to generate neutron flux in the order of one billion neutrons per second 1970 New advances in Laser technology pushes power to higher levels, making inertial confinement appear practical for the first time. Important breakthroughs in this laser technology were made at the Laboratory for Laser Energetics at the University of Rochester, where scientists used frequency-tripling crystals to transform the infrared laser beams into ultraviolet beams 1980 Most laser research turns to weaponization, and energy production possibilities began to seem remote. Work on very large versions continued as a result, with the very large National Ignition Facility in the US and Laser Mégajoule in France supporting these research programs.

16. Laser Inertial Confinement Timeline 2000’s commercially named Fusionstar was developed by EADS but abandoned in 2001. Its successor is the NSD-Fusion neutron generator. Robert W. Bussard'sPolywell concept is roughly similar to the Fusor design, but replaces the problematic grid with a magnetically contained electron cloud, which holds the ions in position and provides an accelerating potential. Current More recent work has demonstrated that significant savings in the required laser energy are possible using a technique known as "fast ignition". The savings are so dramatic that the concept appears to be a useful technique for energy production again, so much so that it is a serious contender for pre-commercial development On May 30, 2009, the US Lawrence Livermore National Laboratory (LLNL), primarily a weapons lab, announced the creation of a high-energy laser system, the National Ignition Facility, which can heat hydrogen atoms to temperatures only existing in nature in the cores of stars. The new laser is expected to have the ability to produce, for the first time, more energy from controlled, inertially-confined nuclear fusion than was required to initiate the reaction. On January 28, 2010, the LLNL announced tests using all 192 laser beams, although with lower laser energies, smaller hohlraum targets, and substitutes for the fusion fuel capsules. More than one megajoule of ultraviolet energy was fired into the hohlraum, besting the previous world record by a factor of more than 30. The results gave the scientists confidence that they will be able to achieve ignition in more realistic tests scheduled to begin in the summer of 2010.

17. Intro to The Actor Network • In the nextslide, we see the “webworky” model of actors currently involved in research regarding fusion energy generation. This was produced using www.issuecrawler.net. • As it is very complex, and has a great deal of listed actors, some narrowing of the field was required. • The issue crawler software analyses the number of co-links which particular websites either make reference, or are made reference to. The number of those links arguably correlates to a certain level of credibility, and therefore is useful in mapping a controversy and the major players involved. • In the slides to follow, I have identified the top 10 actors as indicated by the crawler when it prioritized the “core network and periphery” strength of each, thus indicating higher co-linkage and relevance. • It is important to note that what is represented here is not the entire network, and that there are many less organized or funded projects which do not have the same level of support.

18. The Actor Network

19. The Actor Network 1 – www.iter.org – 53 • ITER Project Website (latin for “the way”) At the Geneva Superpower Summit in November 1985, following discussions with President Mitterand of France and Prime Minister Thatcher of the United Kingdom, General Secretary Gorbachev of the former Soviet Union proposed to U.S. President Reagan an international project aimed at developing fusion energy for peaceful purposes.The ITER project was born.  The initial signatories: the former Soviet Union, the USA, the European Union (via EURATOM) and Japan, were joined by the People's Republic of China and the Republic of Korea in 2003, and by India in 2005. Together, these seven nations represent over half of the world's population. • ITER is currently the largest fusion project under development in the world, and for the purposes of the actor network, represents the main hub through which the majority of actors make reference.

20. The Actor Network • In ITER, the world has now joined forces to establish one of the largest and most ambitious international science projects ever conducted. ITER, which means "the way" in Latin, will require unparalleled levels of international scientific collaboration. Key plant components, for example, will be provided to the ITER Organization through in-kind contributions from the seven Members. Each Member has set up a domestic agency, employing staff to manage procurements for its in-kind contributions.  The ITER Members have agreed to share every aspect of the project: science, procurements, finance, staffing ... with the aim that in the long run each Member will have the know-how to produce its own fusion energy plant.Selecting a location for ITER was a long process that was finally concluded in 2005. In Moscow, on June 28, high representatives of the ITER Members unanimously agreed on the site proposed by the European Union - the ITER installation would be built at Cadarache, near Aix-en-Provence in Southern France. • Source: www.iter.org

21. The Actor Network • 2 – www.jet.efda.org – 41 • JET – A European joint venture The Joint European Torus (JET) investigates the potential of fusion power as a safe, clean, and virtually limitless energy source for future generations. The largest tokamak in the world, it is the only operational  fusion experiment capable of producing fusion energy. As a joint venture, JET is collectively used by more than 40 laboratories of EURATOM Associations. The European Fusion Development Agreement, EFDA for short, provides the work platform to exploit JET in an efficient and focused way. As a consequence more than 350 scientists and engineers from all over Europe currently contribute to the JET program. • JET recently joined ITER Project

22. The Actor Network • 3 – www.pppl.gov – 33 • The Princeton Plasma Physics Laboratory in United States Department of Energy • For the past three decades, PPPL has been a leader in magnetic confinement experiments utilizing the tokamak approach. This work culminated in the world-record performance of the Tokamak Fusion Test Reactor (TFTR), which operated at PPPL from 1982 to 1997. Beginning in 1993, TFTR was the first in the world to use 50/50 mixtures of deuterium-tritium, yielding an unprecedented 10.7 million watts of fusion power. • The DOE Princeton Plasma Physics Laboratory works with collaborators across the globe to develop fusion as an energy source for the world, and conducts research along the broad frontier of plasma science and technology. PPPL also nurtures the national research enterprise in these fields, and educates the next generation of plasma and fusion scientists. • Fusion power research is obviously of high value to the US Government.

23. The Actor Network 4 – www.efda.org - 32 • The European Fusion Development Agreement (EFDA) is an agreement between European fusion research institutions and the European Commission to strengthen their coordination and collaboration, and to participate in collective activities. Its activities include coordination of physics and technology in EU laboratories, the exploitation of the world's largest fusion experiment, the Joint European Torus (JET) in the UK, training and career development in fusion and EU contributions to international collaborations. • promoting training and career development opportunities in fusion, • coordinating EU contributions to a variety of international collaborations outside the responsibility of F4E, • representing fusion in EIROforum, a collaboration between seven of Europe's major scientific collaborative organizations. • Fusion staff working for EFDA are located in either Garching near Munich in Germany or Culham in the UK • Provides the “glue” for many research facilities, thus increasing cohesiveness.

24. The Actor Network 5 – www.fusionforenergy.europa.eu - 30 • The European Joint Undertaking for ITER and the Development of Fusion Energy or 'Fusion for Energy' is a type of European organization known as a Joint Undertaking created under the Euratom Treaty by a decision of the Council of the European Union. • 'Fusion for Energy' is established for a period of 35 years from 19th April 2007 and is situated in Barcelona, Spain. The organization has the following Members which can be likened to “shareholders”: • Euratom, represented by the European Commission; • the Member States of Euratom; • third countries which have concluded cooperation agreements with Euratom in fusion that associate their respective research programs with the Euratomprograms and which have expressed their wish to become Members. • The current Members are therefore the 27 Member States of the European Union, Euratom and Switzerland as a third country. Each Member sits in the Governing Board – the main body which supervises the Joint Undertaking. The Director is the Chief Executive Officer responsible for day-to-day management of the organization. A perfect example of issues and actors “hanging together”. • An Executive Committee of thirteen members assists the Governing Board in a range of matters, in particular, approving the award of contracts. The Technical Advisory Panel also plays an important role in providing advice to the Governing Board and Director on the technical and scientific activities of 'Fusion for Energy'.

25. The Actor Network • 6 – www.psfc.mit.edu - 28 Plasma Science & Fusion Center @ MIT • The Plasma Science and Fusion Center (PSFC) seeks to provide research and educational opportunities for • expanding the scientific understanding of the physics of plasmas, the "fourth state of matter," and to use that knowledge to develop useful applications. The central focus of PSFC activities has been to create a scientific and engineering base for the development of fusion power. Nevertheless, non-fusion applications involving plasmas at the PSFC are numerous and diverse. A recent example is the significant growth of programs in plasma-based technologies, including environmental remediation and hydrogen production.

26. The Actor Network • 7 – www-fusion.ciemat.es - 27The Laboratorio Nacional de Fusión; Spain • The magnetic fusion program of the CIEMAT had its beginning in the earlyeighties and currently focuses around a stellarator-type machine: THE FLEXIBLE HELIAC TJ-II. • 1997 Initial operation of the flexible heliacTJ-II. • 1994 Initial operation of the TJ-IUpgrade. This is the first magnetic confinement device entirely constructed in Spain. • 1990 Euratom decides financing 45% (preferential support) of the TJ-II project when its technical viability is demonstrated. • 1986 Creation of the AsociaciónEuratom-CIEMAT paraFusión. Presentation before EURATOM of the flexible heliac project TJ-II, directed towards demonstrating its scientific interest (Phase I). 1983 Initial operation of the tokamakTJ-I. • Is now allied with the ITER project.

27. The Actor Network • 8 – www.ornl.gov - 25 • Oak Ridge National Laboratory • ORNL is a multiprogram science and technology laboratory managed for the U.S. Department of Energy by UT-Battelle, LLC. Scientists and engineers at ORNL conduct basic and applied research and development to create scientific knowledge and technological solutions that strengthen the nation's leadership in key areas of science; increase the availability of clean, abundant energy; restore and protect the environment; and contribute to national security. • ORNL also performs other work for the Department of Energy, including isotope production, information management, and technical program management, and provides research and technical assistance to other organizations. The laboratory is a program of DOE's Oak Ridge Field Office.

28. The Actor Network • 9 – www.fusion.org.uk - 25Culham Centre for Fusion Energy (CCFE) • is the UK's national laboratory for fusion research. CCFE (formerly known as UKAEA Culham) is based at Culham Science Centre in Oxfordshire, and is owned and operated by the United Kingdom Atomic Energy Authority. • The 80-hectare site just south of Oxford was previously HMS Hornbill, a Fleet Air Arm airfield, before opening as a purpose-built fusion laboratory in 1960. Since then, Culham has made many major contributions to international fusion research and development. Today the UK fusion programme is centred on the innovative MAST (Mega Amp Spherical Tokamak) experiment and employs around 150 people. The programme is funded by the Engineering and Physical Sciences Research Council and the European Union under the EURATOM treaty. • Part of ITER project

29. The Actor Network • 10 – www.nifs.ac.jp - 24 • National Institute for Fusion Science (The Graduate University for Advanced Studies), Sokendai Japan • NIFS carries out research mainly by using a superconduction large helical device (LHD). LHD is also known for its magnetic field confinement system called ‘heliotron’, which was uniquely developed in Japan. With LHD, the institute places greater importance on the following: 1) the research in the generation and confinement of high-temperature high-density plasmas and 2) the analysis of LHD experiments as well as the extensive theoretical and simulation science research by using the supercomputer. • At Large Helical Building, we are constructing the Large Helical Device(LHD). The LHD is the world's largest stellarator with two superconducting helical coils and six superconducting poloidal (vertical field) coils. The design will have a vacuum vessel 3.9m in major radius and 1.6m in minor radius. The helical coils produce a magnetic field of 3 Tesla (1st phase) and 4 Tesla (2nd phase). The LHD will become operational in 1998. • Not a part of ITER project—but shows that there are more approaches than just magnetic and laser confinement being tested and researched.

30. The Race is on… for Magnetism • Under the international project ITER, (latin for “the way”) many industrialized countries have banded together to push their Magnetic Confinement Tokamak toward being the first demonstrable power producing fusion plant in the world. • Studies regarding how, and who to eventually integrate with the power grid with are currently under way. • A "Broader Approach" agreement for complementary research and development was signed in February 2007 between the European Atomic Energy Community (known by its initials EURATOM) and the Japanese government. It established a framework for Japan to conduct research and development in support of ITER over a period of ten years. Within the Broader Approach three projects were set into motion that focus on the following areas: materials testing, advanced plasma experimentation and simulation, and the establishment of a design team to prepare for DEMO, the demonstration power plant which will be the next step after ITER. The Broader Approach projects carry great importance for the advancement of fusion energy and will complement the global efforts on realizing ITER. • Source: www.iter.org

31. The Race is on… for Lasers • During an interview with BBC News, Siegfried Glenzer, the Nif plasma scientist outlined the following narrative: During 30 years of the laser fusion debate, one significant potential hurdle to the process has been the "plasma" that the lasers will create in the hohlraum. The fear has been that the plasma, a roiling soup of charged particles, would interrupt the target's ability to absorb the lasers' energy and funnel it uniformly into the fuel, compressing it and causing ignition. Siegfried Glenzer, the Nif plasma scientist, led a team to test that theory, smashing records along the way. "We hit it with 669 kilojoules - 20 times more than any previous laser facility," Nif's Siegfried Glenzer told BBC News. Adding momentum to the ignition quest, Lawrence Livermore National Laboratory announced on Wednesday that, since the Science results were first obtained, the pulse energy record had been smashed again. They now report an energy of one megajoule on target - 50% higher than the amount reported in Science. The current calculations show that about 1.2 megajoules of energy will be enough for ignition, and currently Nif can run as high as 1.8 megajoules. source: www.iterfan.org

32. The Race is on… for Lasers Dr Glenzer said that experiments using slightly larger hohlraums with fusion-ready fuel pellets - including a mix of the hydrogen isotopes deuterium as well as tritium - should begin before May, slowly ramping up to the 1.2 megajoule mark. "The bottom line is that we can extrapolate those data to the experiments we are planning this year and the results show that we will be able to drive the capsule towards ignition," said Dr Glenzer. Before those experiments can even begin, however, the target chamber must be prepared with shields that can block the copious neutrons that a fusion reaction would produce. But Dr Glenzer is confident that with everything in place, ignition is on the horizon. He added, quite simply, "It's going to happen this year." Source: http://www.iterfan.org

33. Synopsis… for Magnetism • ITER is not an end in itself: it is the bridge toward a first plant that will demonstrate the large-scale production of electrical power and Tritium fuel self-sufficiency. This is the next step after ITER: the Demonstration Power Plant, or DEMO for short. A conceptual design for such a machine could be complete by 2017. If all goes well, DEMO will lead fusion into its industrial era, beginning operations in the early 2030s, and putting fusion power into the grid as early as 2040.

34. Synopsis… for Lasers • NIF will not be used to generate electricityin it’s current form. But NIF experiments should bring fusion energy a major step closer to being a viable source of virtually limitless energy by demonstrating fusion ignition and burn and energy gain in the laboratory. And the timing is fortunate: Energy experts estimate that over the next 75 years, the demand for energy could grow to as much as three times what it is today, while supplies of petroleum and natural gas will decline steadily and may well be exhausted by the turn of the century.

35. Conclusion • At the outset of this assignment, I thought that it would be easy to find plenty of controversies surrounding the multiple approaches to the development of thermonuclear fusion. However, during the process of mapping the actor networks, and following links, it became apparent that a high degree of cohesiveness and cooperation between agencies is occurring, which is made more than apparent with the formation of the ITER project. • There is less argument about whether fusion is possible, we seem to have collectively established that it IS possible. We also seem to have found that the only question left is exactly HOW to achieve confinement. Here, there is really no wrong way, just a multitude of different approaches.

36. Conclusion • On a smaller scale, there have been experiments conducted which arguably show that other approaches to fusion are possible, which HAVE been controversial. • For example, the research of RusiTaleyarkhan from the Department of Nuclear Engineering at Purdue University. • Taleyarkhan's fusion breakthrough was based on a little-understood process called sonoluminescence. It's a process that magically transforms sound waves into flashes of light, focusing the sound energy into a tiny flickering hot spot inside a bubble. It's been called the star in a jar.

37. Conclusion • His results and practices have been thoroughly debated. He has been called a fraud by his own university, and has even lost jobs and much credibility over his claims, along with other colleagues who have worked for him. • This story probably would serve as a better playground for the study of controversy, however, his contributions to the field were stumbled upon late in my research process, and have been disproven enough times to warrant his contributions as menial regarding their impact on the commercial development of thermonuclear fusion energy generationas it currently stands. • Source: http://www.bbc.co.uk/sn/tvradio/programmes/horizon/experiment_prog_summary.shtml

38. Conclusion • In closing, I would like to conjecture that when beginning one’s search for a controversy, computer aided research can be completely useful, if approached correctly. • One cannot assume that controversy will arise out of pure interest in a subject. One must seek the controversy FIRST instead of letting the subject matter find it for them. • The results of my research were a great case for finding cohesiveness within and actor network, as is shown by the issuecrawler’s ability to show me that cooperation among networks is high—however, I believe this makes finding existing controversies more difficult to follow, as it tends not to proioritize actors who are less prominent. • Mayhaps studying both ends of the prioritization spectrum would yield better results when it comes to finding controversies. In later experiments, I shall find this perspective useful.

39. Works Cited/Colinks (top 36) • http://www.iter.org/ • http://www.iter.org/default.aspx • http://www.iterkorea.org/ • http://www.fusion-expo.si/ • http://www.sfa-fuzija.si/ • http://www.enea.it/ • http://www.jet.efda.org/ • http://www.fusionforenergy.europa.eu/ • http://www.kiae.ru/ • http://www.iterfan.org/ • http://www.eso.org/ • http://www.efda.org/ • http://www.usiter.org/ • http://www.iter-india.res.in/ • http://www.pppl.gov/ • http://www.fusion.org.uk/ • http://www.psfc.mit.edu/ • http://soft2010.ipfn.ist.utl.pt/ • http://www.itercad.org/ • http://www.ofes.fusion.doe.gov/ • http://www.ipp.mpg.de/ • http://fire.pppl.gov/ • http://crppwww.epfl.ch/ • http://fusionforenergy.europa.eu/4_1_news_en.htm • http://fusedweb.pppl.gov/ • http://fusioned.gat.com/ • http://ec.europa.eu/research/energy/fu/article_1122_en.htm • http://fusion.gat.com/ • http://fusion.rma.ac.be/ • http://www.ccfe.ac.uk/ • http://www.ipp.cas.cz/ • http://varenna-lausanne.epfl.ch/ • http://www.tokamak.info • http://itpa.ipp.mpg.de/ • http://www.fusionpower.org/