No doubt,the story about farmer stealing kilowatts of power in a desribed way is a pure bullshit.I wonder who has enough imagination to invent and spread nonsenses like that.Few comments regarding the article which has some good but weak & funny points as well. (4)
Mentioned 150 A max for 230 kV power line is a funny figure.This current is even smaller than expected average current of such power line.Single Al/Fe phase conductor cross section 120/20 mm˛ can withstand 400 A continously and 240/40 mm˛ about 650 A. For example,typical EHV line,say 500 kV one,with boundled phase conductor is designed to carry about 1000 A.Of course,in real situation ,the current will depend on loading of consumers. (7)
Maximazing power by choosing arbitrary load (Z=200 ohms) is a no-no. The conclusion about very low power factor is correct only for low output impendances.With higher impendances power factor increases (power throughput doesn't however). (10)
Inserting iron core in the coil in such situation will not
particularly help!Actually I think it will just worsen the thing. As regards advice to farmer how to increase efficiency here are my 2 cents.He may built a resonant converter with natural frequency 60 Hz ,by connecting HV capacitor to the coil.Adequate capacitor size for 1600 H coil would be 17.6 nF.With Q factor in the range 100-200 ,and B-field given in the example ,extracted power will be couple of watts.This is still far from being enough for his needs.Not to mention economy (good point 9 in the article).Good resonant converter for such purpose will not be cheap.Finally,the author seems to be completely forgetting about fact farmer is dealing with 230 kV line and he should better think of utilizing E-fields than B-fields!Calculate specific energy in elementar space volume created by E-field and B-field of 230 kV line and see.