Researchers at the Technology Institute of Costa Rica (TEC) announced the first discharge of high temperature plasma in Latin America on 29 June 2016, joining an elite group of countries who have made advances in harnessing nuclear fusion to produce clean energy.

To produce the discharge, TEC physicists used a device called a stellarator built on the university’s campus in Cartago province.

The first discharge of Costa Rica’s Stellarator-1 (SCR-1) lasted only 4.5 seconds but is considered the most complex applied physics research conducted in the country, TEC officials said during a special ceremony held on 29 June 2016 and broadcast live.

Costa Rica is just the sixth country in the world to have developed a stellarator, along with the U.S., Japan, Spain, Australia and Germany, according to a news release from TEC.

The scientific achievement took six years of research and an investment of $500,000.

Iván Vargas, coordinator of TEC’s Plasma Laboratory for Fusion Energy, said that one gram of energy from the stellarator can generate up to 26,000 kilowatt hours (kWh), enough to power 80 homes for a full month. Plasma technology opens the possibility to generate 100 times more power than a hydroelectric plant.

According to Vargas, plasma is seen by many in the scientific world as the energy of the future — clean and theoretically inexhaustible.

“It’s a special moment for us,” Vargas said. “The SCR-1 is the only [stellarator] in Latin America and one of the few in the world devoted to research of plasma as a future energy source,” Vargas told a group of scientists from various countries who came to Costa Rica to witness the historic first discharge.

In February, German scientists made the first test with their own stellarator in a special ceremony in which Chancellor Angela Merkel was in charge of switching on the first hydrogen plasma. 

How does a stellarator work?

A stellarator uses magnets to confine hot plasma in order to sustain a controlled nuclear fusion reaction. The stellarator looks to reproduce the energy of stars, which are natural fusion reactors.

In stars, the force of gravity and high temperatures fuse together the nuclei of atoms, releasing energy. “We’re recreating on Earth the system used by the universe to generate its main energy source,” Vargas said.

“We must understand that [plasma] is universal, all the stars in our universe produce energy from fusion,” he said, adding that it’s a safe and environmentally-friendly source of energy that doesn’t generate greenhouse gases.

It’s also theoretically an unlimited source of energy, using hydrogen, the most abundant element in the universe.

David Gates, the stellarator physics leader at Princeton’s Plasma Physics Lab (PPPL), sent a video message to Costa Rica, in which he welcomed the country to the small group of nations that have managed to produce high-temperature plasma.

“We welcome Costa Rica to the world of international collaboration in physics and stellarator reactors,” Gates said. “We’re very excited to continue the cooperation between our two universities,” he said. TEC’s Iván Vargas is currently doing an internship at the Princeton lab.

Government officials, professors, students and other special guests observed the experiment through the live broadcast from one of TEC’s campus auditoriums.

The next stage

Vargas said the first test was aimed at controlling the plasma discharge. Researchers also wanted to verify the stellarator’s capacity to control plasma temperatures, which reach above 300,000 degrees Celcius (540,000 Fahrenheit).

Researchers will now focus on the engineering aspects of the device and the physical properties of the plasma it can create.

“Then we will keep working on improvements to the device and in the future, we’ll focus on improving its capacity,” Vargas said.

Plasma applications go beyond energy. There are ongoing investigations of plasma for use in medicine for cancer and skin treatment, and dentistry.

Plasma also has potential for use in the textile industry, for water purification, waste treatment and for energy generation through plasma gasification.

Costa Rican physicist and former NASA astronaut Franklin Chang Díaz is also working on the development of plasma-based space propulsion systems for NASA.

Chang’s VASIMR plasma engine is currently in the testing phase and is considered the leading rocket propulsion technology for taking the first manned mission to Mars.

Source: The Tico Times

Even though ITER will be the biggest fusion device, the efficient use of the remaining space inside its vessel, once all bulky high-tech components will be assembled, is expected to be a hot issue. Perhaps as hot as the fusion reaction of 150 million ˚C that will be confined within its walls by powerful superconducting magnets. One of the conundrums that engineers will have to solve is how to best exploit the limited amount of space they will be left with in order to perform delicate and important tasks such as inspections and maintenance. The multiple inter-connected pieces of equipment and the exposure of some of them to radioactivity do not qualify human intervention as an option. Therefore, the search for ITER’s compact but reliable Big Brother system needs to begin. 

Marco Van Uffelen, F4E Remote Handling, explains that “we need to draw lessons from space applications and fission technology in order to manufacture cameras that are small in size and strong enough to sustain the ITER in-vessel environment. Basically, we are developing the first of a kind and we are entering an exciting phase of the project because with the help of companies and laboratories we are making headway.” It is estimated that the total number of cameras scattered in the machine will be in the range of one hundred and will consist of two types: oversight cameras giving engineers a broad angle inside the vacuum vessel and embedded cameras on tooling or robotics which will help us have vision inside tightly confined spaces of tooling.

The fruitful collaboration between F4E and Oxford Technology Limited (OTL) has generated different subsystem mock-ups that will soon be tested. OTL has successfully involved laboratories, which boast a solid track record in R&D, to develop different parts:ISAE, Toulouse, is responsible for the image sensors; CEA for the illumination system and the Jean Monnet University Saint Etienne for the optic system. Currently, the mock-up measures 15 mm and fits inside a 1 EUR coin. In future, the camera prototype will measure 40 mm x 40 mm x 70 mm.

Experts have been working on the development and validation of these subsystems for almost a year and a half and the next phase will be to test their resistance in a nuclear facility. In Belgium’s SCK-CEN the subsystems will be exposed to Gamma radiations and after each irradiation step they will be analysed. The tests on FURHIS (Fusion for Energy Radiation Hard Imaging System) are expected to be concluded on March 2017 and on the basis of their findings the prototyping phase will begin.

Source: Fusion for Energy

Like a lunar module checking its landing coordinates one last time, the cylindrical tank with six metal feet hovered silently over the Tritium Building. The event was significant. Part of ITER's water detritiation plant system, the tank had the honour of being the first component to be installed in the Tokamak Complex.

In the Tokamak Building, tritium needs to be removed from the atmosphere of different "spaces" such as the vacuum vessel, the port cells, the neutral beam injector, etc.

A successful start with helium plasma / hydrogen plasma to follow at the beginning of 2016.

On 10th December 2015 the first helium plasma was produced in the Wendelstein 7-X fusion device at the Max Planck Institute for Plasma Physics (IPP) in Greifswald. After more than a year of technical preparations and tests, experimental operation has now commenced according to plan. Wendelstein 7-X, the world’s largest stellarator-type fusion device, will investigate the suitability of this type of device for a power station. 

Following nine years of construction work and more than a million assembly hours, the main assembly of the Wendelstein 7-X was completed in April 2014. The operational preparations have been under way ever since. Each technical system was tested in turn, the vacuum in the vessels, the cooling system, the superconducting coils and the magnetic field they produce, the control system, as well as the heating devices and measuring instruments. On 10th December, the day had arrived: the operating team in the control room started up the magnetic field and initiated the computer-operated experiment control system. It fed around one milligram of helium gas into the evacuated plasma vessel, switched on the microwave heating for a short 1,3 megawatt pulse – and the first plasma could be observed by the installed cameras and measuring devices. “We’re starting with a plasma produced from the noble gas helium. We’re not changing over to the actual investigation object, a hydrogen plasma, until next year,” explains project leader Professor Thomas Klinger: “This is because it’s easier to achieve the plasma state with helium. In addition, we can clean the surface of the plasma vessel with helium plasmas.” 

The first plasma in the machine had a duration of one tenth of a second and achieved a temperature of around one million degrees. “We’re very satisfied”, concludes Dr. Hans-Stephan Bosch, whose division is responsible for the operation of the Wendelstein 7-X, at the end of the first day of experimentation. “Everything went according to plan.” The next task will be to extend the duration of the plasma discharges and to investigate the best method of producing and heating helium plasmas using microwaves. After a break for New Year, confinement studies will continue in January, which will prepare the way for producing the first plasma from hydrogen.

Background

The objective of fusion research is to develop a power source that is friendly to the climate and, similarly to the sun, harvests energy from the fusion of atomic nuclei. As the fusion fire only ignites at temperatures of more than 100 million degrees, the fuel – a thin hydrogen plasma – must not come into contact with cold vessel walls. Confined by magnetic fields, it floats virtually free from contact within the interior of a vacuum chamber. For the magnetic cage, two different designs have prevailed – the tokamak and the stellarator. Both types of system are being investigated at the IPP. In Garching, the Tokamak ASDEX Upgrade is in operation and, as of today, the Wendelstein 7-X stellarator is operating in Greifswald.

At present, only a tokamak is thought to be capable of producing an energy-supplying plasma and this is the international test reactor ITER, which is currently being constructed in Cadarache in the frame of a worldwide collaboration. Wendelstein 7-X, the world's largest stellarator-type fusion device, will not produce energy. Nevertheless, it should demonstrate that stellarators are also suitable as a power plant. Wendelstein 7-X is to put the quality of the plasma equilibrium and confinement on a par with that of a tokamak for the very first time. And with discharges lasting 30 minutes, the stellarator should demonstrate its fundamental advantage – the ability to operate continuously. In contrast, tokamaks can only operate in pulses without auxiliary equipment.

The assembly of Wendelstein 7-X began in April 2005: a ring of 50 superconducting coils, some 3.5 metres high, is the key part of the device. Their special shapes are the result of refined optimisation calculations carried out by the “Stellarator Theory Department”, which spent more than ten years searching for a magnetic cage that is particularly heat insulating. The coils are threaded onto a ring-shaped steel plasma vessel and encased by a steel shell. In the vacuum created inside the shell, the coils are cooled down to superconduction temperature close to absolute zero using liquid helium. Once switched on, they consume hardly any energy. The magnetic cage that they create, keeps the 30 cubic metres of ultra-thin plasma – the object of the investigation – suspended inside the plasma vessel.

The investment costs for Wendelstein 7-X amount to 370 million euros and are being met by the federal and state governments, and also by the EU. The components were manufactured by companies throughout Europe. Orders in excess of 70 million euros were placed with companies in the region. Numerous research facilities at home and abroad were involved in the construction of the device. Within the framework of the Helmholtz Association of German Research Centres, the Karlsruhe Institute of Technology was responsible for the microwave plasma heating; the Jülich Research Centre built measuring instruments and produced the elaborate connections for the superconducting magnetic coils. Installation was carried out by specialists from the Polish Academy of Science in Krakow. The American fusion research institutes at Princeton, Oak Ridge and Los Alamos contributed equipment for the Wendelstein 7-X that included auxiliary coils and measuring instruments.  

Source: Max Planck Institute for Plasma Physics

Next week: start with helium plasma planned / hydrogen plasmas are to follow in 2016

With the generation of the first plasma the Wendelstein 7-X fusion device is scheduled to go into operation on time in December 2015 at the Max Planck Institute for Plasma Physics (IPP) in Greifswald/Germany. The experiments will begin with a plasma consisting of the noble gas helium. The Wendelstein 7-X fusion device is the world’s largest and most advanced device of the stellarator type. Its objective is to investigate the suitability of this type for a power plant.

After nine years of construction and more than one million installation hours the main assembly of Wendelstein 7-X was completed in April 2014. Since then, preparations for operation have been conducted. One by one the technical systems have been tested – the vacua in the cryostat and the plasma vessel, the cooling system, the superconducting coils and the magnetic field produced by them, the control system as well as the heating and measurement devices.