%20Used%20for%20Power%20Transmission%20Instead%20of%20Direct%20Cu.webp){kind=spacer} |
| Why we use AC instead of DC in transmission |
Why Is Alternating Current (AC) Used for Power Transmission Instead of Direct Current (DC)
Many people wonder why alternating current (AC) is used for transmitting electricity over long distances instead of direct current (DC), even though both types of current can carry electrical energy. In this article, we will explore the key reasons why AC is preferred for power transmission.
Alternating current (AC):
AC is a type of electrical current that periodically changes direction (switching between positive and negative). Its frequency is measured in hertz (Hz), with most countries using either 50 Hz or 60 Hz, meaning the current changes direction 50 or 60 times per second.
 |
| AC current diagram |
AC is considered the backbone of electrical power in our daily lives. It is used in various applications, including homes for operating appliances such as washing machines, refrigerators, and air conditioners, as well as in residential buildings, industrial companies, and commercial facilities. One of the key advantages of AC is its ease of transformation, allowing it to be efficiently transmitted over long distances using electrical transformers.
What Is Direct Current (DC):
Direct current (DC), also known as constant current, is the opposite of alternating current (AC) because it does not change direction and has no frequency. Its voltage remains steady over time, making it ideal for electronic devices that require a stable power supply, such as smartphones, computers, and sensitive electronic components.
 |
| DC current diagram |
DC is typically generated through chemical reactions (such as in batteries) and renewable sources like solar panels. One of its key advantages is its ability to be stored, making it widely used in systems requiring precision and high control, such as electronics engineering and electric vehicles.
Why Is Alternating Current (AC) Used for Power Transmission Instead of Direct Current (DC):
One of the main reasons for using alternating current (AC) in power transmission is its ability to be easily transformed using electrical transformers, which operate based on electromagnetic induction. AC can be converted to very high voltages, significantly reducing transmission costs over long distances.
The higher the voltage, the thinner the transmission wires needed, as higher voltage reduces electrical resistance and energy loss. This is why power transmission lines are often thin, which helps minimize power loss and lower the cost of building electrical grids.
Ease of Controlling Alternating Current (AC):
Alternating current (AC) is easy to regulate in power transmission networks and can be efficiently distributed through substations and distribution transformers. It is well-suited for local distribution networks, where the voltage is stepped down to 220V or 110V, depending on the country's electrical system, ensuring safe and reliable power delivery to homes and businesses.
Reduced Energy Loss :
When electricity is transmitted over long distances, energy loss occurs due to resistance in the power lines. Using higher voltage reduces the current flow, which in turn minimizes energy loss as heat. Since AC voltage can be easily stepped up, it allows for more efficient and cost-effective transmission.
Conclusion :
While DC transmission is still used in specific applications, such as high-voltage direct current (HVDC) systems, AC remains the dominant method for power transmission due to its efficiency, ease of transformation, and cost-effectiveness.