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The discovery of superconductivity at relatively higher temperatures in a non-cuprate system, LnFeAsO1 [?] xFx (Ln = lanthanides) has created tremendous activity among the reseachers in this field. This review is an overview on the present status and the future scope for iron pnictides. The various structural categories of iron based superconductors, the structural aspects, different preparation techniques of the material and the necessity for its optimization are discussed. The highlighting features of iron pnictide, i.e. the very high upper critical field, moderate magneto-transport and thermal properties, are also included. The article gives a summary of the prevailing arguments of researchers to relate the material to cuprates and also the comparative features of classical and MgB2 superconductors.
Let me add that critical field could run as high as 300 T at 0K for some of the materials. That means that a 15 T field with a 2 m coil is doable. i.e. it ups the power density by a factor of 5. Not too shabby. Of course if we go to 1m the power doubles. And now you have upped the power density by a total factor of 80 (did I do that calc right?).
Any way my gut feeling is that power producing machines will use coils with a 1 m bore (maybe less). What does that mean? A power producer in volume will come in at under $2 million or so for the reactor vessel and coils. This is starting to get interesting. Power supplies at $2.5 mil or less. Vacuum pumping at $1 million or less. Instruments and controls at under $1 million. So the energy producer should be about $6.5 mil. Power collection another equal amount. So you are talking $13 mil for 100 MW - in production. At $1/w capital cost d no fuel cost electricity would cost about $.05/KWh at a capital cost of $.13/W you are talking electricity at under $.01/KWh. Certainly under $.02/KWh. That means early retirement for most existing power plants.
The only fly in the ointment is that all we have is lab samples. This stuff is probably 5 years away from production and 10 years from reasonable cost.