Knowing
* earth spin and translation movement around sun,
* sun have a big magnetic field,
* a variable flux can generate a induced voltage (and current) into the circuit
Would it be posible to receive in a coil that energy?
Perhaps it's just enough to detecting the earth movement relative to magnetic field, or if it were strong enough even for use the energy.
It doesn't seem to be so strong because if it where perhaps every coil in earth without a current generated by this flux variation.