Watts News
 Published for the members of North Itasca Electric Cooperative
VOL. 22 NO. 10  -  October 2019

Idle transformers also consume energy


Load losses are created from heat produced from the resistance to current flow through the wires (also known as conductors). Losses increase when a load is placed on a transformer. Current flows through conductor wires and the transformer’s core. One set of wires carry high voltage and low current from the electrical panel (primary side), while another set of conductor wire carries low voltage, high current on the appliance (or secondary side). When inducing current from the primary side to the secondary side through the transformer’s core, current flow under load results in load or coil loss.

No-load losses happen when transformers consume energy even though there are no electrical appliances running. This happens in the transformer’s core from magnetizing current. This is when the core is constantly being magnetized and demagnetized. The name for this is hysteresis loss. Another type of loss is eddy current loss, which happens even under no load conditions. Circular currents happen when there is no load on the secondary side (appliance side) and the primary side (from electrical panel) is still energized. Even though these transformers are small, and losses are minimal, they still exist.

What about those transformers on the power poles?

These same principles apply to that transformer on the pole that supplies electricity power to your home. Transformer losses occur even for those seasonal members which come up to the cabin just a few weekends a year. The energy lost from them is still charged to North Itasca Electric as electricity used. These losses are passed through to members within the base charge each month.