In 1986, compounds were discovered that became superconducting at a critical temperature as high as 30 K. Since then, research to find better materials has been intense. The goal was to get the critical temperature above 77 K, the point at which nitrogen becomes liquid. Liquid nitrogen is much, much cheaper and easier to produce than liquid helium, which is liquid below 4 K. The 73°C difference between 77 and 4 K does not seem much. We encounter such a change every time we boil a cup of coffee. However, since one can never go below absolute zero, it is the distance from absolute zero that is important. Seventy-seven kelvin is 19 times farther from 0 K than is 4 K; and, of course, there is no shortage of nitrogen. The goal has already been achieved; three superconductors have been found that work at liquid nitrogen temperatures. The record as of 2009 is 135 K, well above 77 K. Typically, the compound is complicated: HgBa2Ca2Cu3Ox. Until searches can be made by computer, finding new compounds will be slow; but it is a reasonable expectation that large-scale production of a high-temperature superconductor will be possible by the time DEMO is built. Maybe a room-temperature superconductor will have been found by that time. The machine would be much simpler and cheaper.