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Nice demo! Quick back of the envelope calculation for the current to overcome dynamic friction:

I = mu_friction * Mass * grav_acc / (Turns_per_length * Area * Br_magnet)

Say Mass=0.1kg, coil at 600 turns per metre, hand-wave mu_friction=0.2, and a rare-earth retention Br=1Tesla, gives a current of 3A. Maybe more to chug along, would deplete a 2000mAh battery in about 30 minutes. Wire looks about 20 AWG, should get quite hot.

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Which would theoretically use more energy, levetating the "train", or overcoming the friction?

(I"m not suggesting this design can levitate, just curious about the trade-off.)

The train never levitates.

Levitating.

Since overcoming the friction can be achieved through approaches like coating the wire in ultra low friction material which will consume no power to operate.

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