Reactive Power Inside the Network
The reactive power is the alternating component of the electrical power and is usually undesirable or should be kept as low as possible. The alternating component always reverses its direction (sign, positive to negative to positive etc.), since this power oscillates back and forth between the consumer and the energy source. For purely resistive loads (electrical resistance), the angle φ is equal to zero and thus the reactive power is also zero. However, this is different for inductive consumers (electrical coil) and capacitive consumers (electrical capacitors), since electric voltage is fed back into the grid. Capacitive and inductive consumers differ only in the respect that the phase shift occurs in different directions (the result remains the same).