MIT refreshes fusion reactor with modern superconductors Rare-earth barium copper oxide (REBCO) superconducting tapes could mean earlier practical fusion reactors, according to MIT.
The key is stronger magnetic fields, which shrink the size of tokamak [chamber] required, and subsequently simplify all that follows.
It �just ripples through the whole design. It changes the whole thing,� said MIT nuclear scientist Professor Dennis Whyte.
Fusion power increases with the fourth power of magnetic field, so 2x field produces 16x power. �Any increase in the magnetic field gives you a huge win,� said post-grad Brandon Sorbom.
2x magnetic field is not available with REBCO, but there is enough for 10x fusion power, said MIT.
By combining REBCO magnets with known fusion principles, the team has designed a research reactor, and potential prototype power plant, and described it in a paper in the journal Fusion Engineering and Design.
It is half the diameter of the ITER fusion reactor to be built in France (designed before the REBCO superconductors), power output would be the same without any any new physics. �We�re not extrapolating to some brand-new regime,� said Whyte.
As with ITER, continuous operation would be possible.
Suiting it to research, the core of the MIT reactor can be removed without dismantling the entire machine.
Liquid rather than solid materials surround the fusion chamber allowing easy circulation and replacement. �It an extremely harsh environment for [solid] materials,� said Whyte.
 
�Devices of a similar complexity and size have been built within about five years,� said MIT.
Estimates are that power out would be 3x power in, increasing to five or six times with improvements in the design.
UK firm Tokamak Energy is proposing something very similar.