[chihuahua]

I'm just guessing, but I imagine if you have a way of maintaining something at a temperature of millions of degrees, there's always a way to transfer that heat to some other thing. For example, by moving a gas past the very hot object, thus heating up the gas, and then moving the gas through a more conventional heat exchanger, where you generate steam for a steam turbine. Depending on the speed of the gas, it absorbs energy but isn't necessarily heated to the same temperature of millions of degrees, so it doesn't destroy the heat exchanger.

I think this is somewhat similar to how a fission reactor is used to drive a steam turbine in an ordinary nuclear (fission) power plant.