In the pulse charging and discharging of energy storage inductors, the influence of I2R heating, magnetic diffusion skin depth, and eddy current losses must be evaluated. These effects are not easily treated analytically. To address these problems, the system can be constructed according to governing scaling laws. The performance of the model can then be evaluated and scaled up to predict actual system performance. The scaling laws as applied to a 1O-MJ homopolar generator charging a 2-MJ cryogenic aluminum Brooks coil are presented in this paper. System parameters measured on the scale model are compared to parameters subsequently measured on the full-size equipment.