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Comment by imglorp | Hacker News Reader

What seems to be the trouble getting some of these to market? There seems to plenty of demand.

Is this a "Who Killed the Electric Car" conspiracy thing? A VC thing? Or a vaporware/chemistry-is-hard thing?

I guess that most of these are a science journalism thing: http://www.phdcomics.com/comics/archive/phd051809s.gif

For example, there was news recently about a breakthrough discovery of a -70C superconductor. The media spun it as if loss-free electricity transport and maglev trains are just around the corner. But in reality, this material (Hydrogen Sulfide) required 2 million atmospheres of pressure for superconducting at this temperature.

No conspiracy or lack of funding is behind the lack of practical applications, in this case it is just utterly unfeasible outside of a laboratory. But even if the material will never make it to the market, it's still a scientific breakthrough that will give scientists new understanding of how the processes work, and perhaps lead to other discoveries with more practical applications in 2, 20 or 200 years.

But a -70C superconductor could theoretically be used in space environment where the temperatures are even colder, no?

You still have to reproduce the immense pressure.

Space is "cold", but the problem is that it's hard to get rid of waste heat in space since you aren't surrounding by a heat-carrying fluid (air). Therefore a -70c superconductor would still require a large cooling apparatus to function properly.

Yeah that threw me too when I thought the same thing I never thought about how difficult it would be to get rid of heat in space I figured just let it go out into space not thinking there isn't anything to send the heat into; no medium.

NASA has a nice info page about it:

http://science.nasa.gov/science-news/science-at-nasa/2001/as...

Basically, there's no convection, so the only way to dump heat is by radiation.

And since a radiator absorbs as well as it emits, you need to create a shade with reflective material and point a directional radiator in its shadow at the emptiest space you can see.

So sure, superconductors could be really cold in space, but if their solar shade or thermal control system fails, they are suddenly really hot.

But waste heat is a valuable resource, thermoelectric generators could turn it into electricity, for example.

Yeah, you still need to get rid of the heat eventually. For example, thermoelectric generators depend on a temperature gradient to function, but you can't maintain a gradient without some kind of heat sink that draws heat away from the "cold" side.

That still sounds useful for something like a moon-based spaceport where they can drill heat sinks into the ground. Maglev catapults would help cut the amount of fuel they need to transport or produce.

A good battery specific coverage of this was http://www.amazon.com/The-Powerhouse-Inside-Invention-Batter...

What seems to be the trouble getting some of these to market?

Science.

... & engineering. Even if the science is well understood, the processes required to mass produce it at a cost that will make it competitive in the marketplace are not always a given.

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