# Artificial planetary magnetic field

I wonder how difficult it is to create an artificial planetary magnetic field with generators? What power they would need?

The question is inspired by thinking about possible colonization of Jupiter's moons Io and Europa which are located inside the Jovian radiation belt. Is it possible to create with easy means an artificial magnetic field such that it to shield the surfaces of these moons from radiation? Or it would require astronomical amount of power?

By easy means I mean a device that would not require power greater that normal industrial power plant, best of all, solar-powered or based on once-charged superconductor coils.

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Related question physics.stackexchange.com/questions/53184/… –  Jitter Jan 13 at 8:00

According to this article the energy stored in the Earth's magnetic field is about $10^{26}$ ergs or $10^{19}$J. According to Wikipedia the annual global generation of electricity is about 20,000TWh, which is between $10^{19}$ and $10^{20}$J, so actually we already produce enough power to generate the Earth's magnetic field.
You seem to be comparing quantities with different units. By itself, the fact that there are $\ge 10^{19}\,\mathrm{J}$ stored in the Earth's magnetic field tells you nothing about the power needed to generate it, because you also have to know how rapidly that energy is dissipated. If the dissipation time scale is about a year then fair enough, but otherwise comparing our annual energy production (Joules per year) to the total energy in the field (Joules) isn't terribly meaningful. –  Nathaniel Sep 9 '13 at 8:05