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A new National Geographic series on renewable energy, called "Positive Energy," will be featuring the ITER Project in one of its upcoming episodes.

The episode will be viewable on the National Geographic Channel in Europe on Wednesday 1 November at 10:00 p.m. 

It has already been broadcast on the National Geographic Channel in Africa and China (25 October) and in the Americas (18 October).

See more on the "Positive Energy" website.

For hydrogen atoms to fuse into helium, the heat of the ultrahot plasma in the tokamak must be maintained. But, like boiling water, plasma has blobs (or bubbles) that percolate within the plasma edge, reducing the performance of the plasma by taking away heat that sustains the fusion reactions.

Now, scientists at the Princeton Plasma Physics Laboratory (PPPL) in the US have completed new simulations that could provide insight into how blobs at the plasma edge behave. The simulations, produced by a code called XGC1 developed by a national team based at PPPL, performed kinetic simulations of two different regions of the plasma edge simultaneously. This ability produces a more fundamental and fuller picture of how heat moves from plasma to the walls, potentially causing damage.

Blobs play an important role in the outward movement of particles in plasma. Blobs cause approximately 50 percent of the particle loss at the plasma edge, and researchers have observed blobs in a wide range of plasma devices, including tokamaks, figure-eight-shaped fusion devices known as stellarators, and linear machines. "The big picture is that blobs can pull energy and particles out of the plasma, and you don't want that," said PPPL physicist Michael Churchill, lead author of a paper describing the results in the journal Plasma Physics and Controlled Fusion. Churchill said. "You want to keep things confined."

Read more on the PPPL website.

-- Physicist Michael Churchill

Researchers led by the Princeton Plasma Physics Laboratory (PPPL) have proposed an innovative design to improve the ability of future fusion power plants to generate safe, clean and abundant energy in a steady state, or constant, manner. The design uses loops of liquid lithium to clean and recycle the tritium, the radioactive hydrogen isotope that fuels fusion reactions, and to protect the divertor plates from intense exhaust heat from the tokamak that contains the reactions.

"There are many challenges to developing fusion energy and the handling of heat on divertor plates is among them," said PPPL physicist Masa Ono, lead author of a paper about the design published in the journal Nuclear Fusion. "We wanted to see how we can protect the divertor plates and keep the fusion chamber clean."

The system that Ono and colleagues designed calls for pumping liquid lithium in and out of a tokamak, a type of magnetic fusion device, to maintain steady state operation while cleaning out dust and other impurities from the plasma and safeguarding the divertor. The lithium, a silvery metal that readily combines with other elements, would serve a number of functions, including protecting the divertor plates, capturing tritium for recycling, and removing dust and other unwanted elements.

Continue reading on the PPPL website.

-- Physicist Masa Ono of the Princeton Plasma Physics Laboratory.