Why is ac preferred over dc?
Another reason is that AC is simpler and cheaper to generate using alternators, whereas DC requires more complex equipment for large-scale generation.
AC (Alternating Current) is preferred over DC (Direct Current) for power transmission because it can be easily stepped up or down using transformers, which reduces energy loss over long distances.
Historically, AC became the standard during the "War of Currents" because Nikola Tesla and Westinghouse demonstrated its efficiency for national grids compared to Thomas Edison’s DC systems.
DC is less efficient for long-distance transmission. AC allows high-voltage transmission, which minimizes current and reduces I²R losses in the wires.
AC also easily supports three-phase systems, which are used in industrial machinery, whereas DC does not have a simple equivalent.
Fun fact: With modern technology, high-voltage DC (HVDC) is used for very long distances, but for most countries’ grids, AC is still preferred.
AC is also safer to switch on and off in high-voltage applications, which is another reason it’s used over DC for power lines.
However, DC has advantages in electronics and battery-powered devices, but for grid-level electricity, AC dominates due to transmission efficiency and versatility.