Answer: The Corona Effect is a phenomenon where the air surrounding a high-voltage conductor becomes ionized, leading to a partial electrical discharge. This can be observed as a faint, bluish-purple glow, accompanied by a hissing sound and the production of ozone gas. The Corona Effect is undesirable as it causes power loss, radio interference, and can accelerate the aging of equipment. It becomes a design concern for power lines at 230 kV and higher. The effect can be mitigated by using larger conductor diameters, bundle conductors, and specific hardware to reduce the electric field gradient at the conductor's surface.