Sähkönhäviö

Sähkönhäviö refers to the loss of electrical energy that occurs during the transmission and distribution of electricity. This energy loss is an unavoidable consequence of physical processes within electrical systems. The primary mechanisms contributing to sähkönhäviö include resistive losses, also known as Joule heating, and core losses in transformers.

Resistive losses occur in conductors like power lines and cables due to their inherent electrical resistance. When electric current flows through these conductors, a portion of the electrical energy is converted into heat, dissipating into the surrounding environment. The amount of energy lost in this manner is proportional to the square of the current and the resistance of the conductor. This is why power lines are often designed with high voltages to reduce the current needed to transmit the same amount of power, thereby minimizing resistive losses over long distances.

Core losses, mainly found in transformers, consist of hysteresis losses and eddy current losses. Hysteresis losses are associated with the energy required to repeatedly magnetize and demagnetize the iron core of the transformer as the alternating current changes direction. Eddy currents are circulating currents induced within the conductive core by the changing magnetic field. These currents also generate heat due to the core's resistance. Minimizing these losses is crucial for the efficient operation of transformers, which are essential components in stepping voltage up or down in the power grid.

Overall, sähkönhäviö represents an economic and environmental cost. Efforts are continuously made to reduce these losses through various engineering solutions, such as using materials with lower resistance, optimizing conductor sizes, and improving transformer designs.