What type of current is more efficient to transport over long distances?

When it comes to transporting electrical power over long distances, alternating current (AC) is more efficient than other forms of current like direct current (DC). The primary reason for this lies in the ability to use transformers with AC to step up the voltage for transmission. Higher voltage levels reduce the current flowing through the transmission lines, which in turn minimizes energy losses due to resistance in the wires.

These energy losses manifest as heat, and since resistance is proportional to the current squared (I²R losses), decreasing the current by using higher voltage for transmission significantly reduces these losses. While direct current can also theoretically be used for long-distance transmission—especially with advancements in high-voltage direct current (HVDC) technology—traditional AC systems have established infrastructure and technologies such as transformers that have made them the standard for efficiency in power distribution over large distances.

Alternating current also allows for easier generation and integration of power from various sources, including renewable energy systems, reinforcing its position as the more efficient option for long-distance power transport.