It's also worth pointing out that this isn't doing any nuclear fusion; it's a test bed to verify the stellarator's particle confinement and efficiency at heating plasma [1].

    Achieving these objectives does not require producing 
    an energy-yielding fusion plasma. This is because the 
    properties of an ignited plasma can largely be 
    transferred by the ITER tokamak to stellarators.
    Wendelstein 7-X can therefore dispense with the use
    of the radioactive fusion fuel, tritium, thereby
    greatly reducing costs.

This is why it's so much cheaper than ITER to build; they're building a part of a nuclear fusion reactor.

[1] http://www.ipp.mpg.de/w7x