What problems exactly? The fringe field of an MRI is only a few meters outside the bore before it drops off to 1 Gauss. Especially with all the shielding around the machine there is not really a problem with it with normal use. The power consumption of the MRI machine itself are also pretty modest. To keep the magnet on field and superconducting you'll only need to power the helium pump.

The biggest power consumer in an MRI system is the gradient system, which is only necessary for generating images. These need powerful amplifiers to generate the RF pulses.