Russia and Italy announced on Monday that they will collaborate to build a new tokamak fusion reactor called Ignitor. Following talks between Italian Prime Minister Silvio Berlusconi and his Russian counterpart Vladimir Putin, other ministers signed a memorandum of understanding to work together on building the Italian-designed device on Russian territory.
The reactor is the brainchild of Bruno Coppi of the Massachusetts Institute of Technology who worked on MIT's Alcator tokamaks from the 1970s until the present day.
A tokamak is a doughnut-shaped vessel in which researchers use powerful magnet fields to squeeze and heat a plasma of hydrogen isotopes until the nuclei fuse together forming helium and releasing large amounts of heat. A lot of energy has to be put into such a reaction to hold the plasma in place and raise it to the required temperature. The ultimate goal is to achieve "ignition," the point at which the fusion reactions themselves provide enough energy to keep the process running without an external heat source, and excess energy is siphoned off to convert into electricity. The world's largest tokamak, called ITER, is about to begin construction in France and is not expected to get all the way to ignition on its own—it will still need some external heating.
Ignitor takes a different approach than ITER, using a much smaller and more compact tokamak (it's radius is 1.3 meters compared with ITER's 6.2 meters) and a much stronger magnetic field to compress the plasma.