High-temperature superconductors hype and failure to solve power transmission

The Kresge talk, the faculty-member confrontation in the dean's office, the missing levitated trains 17 years later.

And they only cost 100 bucks apiece for a knife, where you can buy one for five or ten bucks out of steel. But I like them. My daughter-in-law really liked them — she used to chip them all the time. In any case, it never became the huge market. Then there was conductive polymers. Then there was high-temperature superconductivity. I told some of you offline the story: IAP in the department, mid-90s, I had to give a talk over at little Kresge to a bunch of people from industry.

The lecture's central extended case. 1988-89 discovery; NSF policy that all grants required HTSC keywords for eighteen months; 75% of the MIT materials department pivoting; the four tenured holdouts who knew critical current would not scale.

In 1988 or '89 they discovered high-temperature superconductors. You could not get a research grant from the National Science Foundation for a year and a half unless it had the words "high temperature superconductor" in it. Seriously. Every new grant — they basically set a policy, because this was going to change the world overnight.

Central teaching case of §6. The 1986–1989 high-Tc superconductor boom that promised to solve copper-bottleneck problems under New York City; failed because critical temperature alone is insufficient — you also need critical current density, which requires pinning centers smaller than an electron. Used to demonstrate the "limits of materials" principle developed in §7.

So what did they do? They had the salvation in 1989. What was the salvation? Superconductors. High-temperature superconductors. The problem is this one didn't work. I always say the only good thing that came out of high-temperature superconductors is I got my office on the great court, when Greg Yurek resigned in 1989 to start American Superconductor. American Superconductor has never made money. They certainly get hundreds of millions of dollars in government research grants and industrial research grants because there is this promise of superconductivity as a material that would solve all the problems of all the power in the big cities, because you don't have enough room to carry all the power to all those buildings. They still have the problem and they're running out of space, and it will limit the ability to build buildings as big as we want.

Extended treatment. The MIT materials department's four tenured superconductivity professors refused to join the bandwagon; only the untenured one did. Twenty-five years later we're still not riding maglev trains. Critical current density was the property nobody improved.

That's not to say that the high-temperature superconductors haven't found a niche. Anybody know what their niche is? The generators for wind turbines. Turns out you really need lightweight up there, and those generator shafts are steel shafts that can be twenty inches in diameter in one of these really big wind turbines. You want something that has better electrical conductivity than just straight copper. Copper is pretty heavy, silver is pretty heavy too. These superconductors are actually silver wires, but if you cool them to liquid nitrogen temperatures you'll get some superconductivity in this silver matrix.