Robert J. Bradbury (
Wed, 1 Sep 1999 09:29:35 -0700 (PDT)

On Tue, 31 Aug 1999, CountZero wrote:

> We don't have a shortage of energy, one way or another we can
> generate/capture enough for most purposes that are currently relevant,
> the problem is lack of a sufficiently energy dense storage media (btw,
> the jet pack of the '60s used H2O2).

Actually I would argue that the problem you can't controllably release the energy. Hydrogen bombs are very dense energy storage devices. :-) But if you compare the mass of a tokomak to the mass of the fuel in it, the device weighs much more than the fuel.

In the area of storage density, I believe the work at NASA to create mono-atomic hydrogen frozen in He and use it as a rocket fuel, could "effectively" be very dense. But you are going to need a very interesting "plant" to create the fuel. It isn't something you could use to power your laptop.

> If my understanding of super conductivity is correct, a super conducting
> coil should be able to store an arbitrarily large amount of energy.
> Is this correct?
I don't believe so. At some current density, I believe you setup a magnetic field that disrupts material properties that allow superconductivity. I think the highest-field magnets have a problem with the material simply staying together, so this problem would presumably apply to superconductors as well as you keep increasing the field density.

One of the physics gurus may want to comment more.