In the case of the transformer, not all the energy is stored in the field, as the secondary takes energy from the field at the same time as the primary supplies it. The secondary tries to collapse the field, while the primary tries to maintain it. In the near-field, this amounts to a direct interaction of charges between the secondary and the primary, and the field is the coupling vector. As soon as there's a delay in which we hope to create a field at one moment, then use it at a later moment, only the energy of the field can be recovered. What's more, outside electromagnetic waves, this is an impossibility, since current and magnetic field are one and the same reality. You can't interrupt a current instantaneously in a primary inductive circuit since the collapsing field variation tries to maintain it. You have to close the secondary circuit at exactly the same moment as you open the primary circuit, and you'll never have anything but the energy of the field at that moment.
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"Open your mind, but not like a trash bin"
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