What Is the Difference Between AC and DC Current?

In this post, our electricians discuss AC vs DC current so you can learn more about how alternating current and direct current works, how they differ, and how both are used in real-life applications.

Electronics are now a staple in every household, but have you ever stopped to think about the type of electricity that powers them?

Electricity generally comes in two forms, as an alternating current (AC) or as a direct current (DC). Both are used to power your appliances and electronic devices at home, so below we’ll explain what is the difference between AC and DC current.

What Is Alternating Current (AC)

Alternating current is a type of current where the electrons continuously switch directions, occasionally moving forward or backward. It alternates directions while flowing in the circuit, with the polarity and strength of the current varying with respect to times.

AC power was invented by Nikola Tesla as a solution to the problem that direct current had regarding DC’s inability to be converted into higher or lower voltages.

Generally, AC power is the current flowing through power lines and outlets in households primarily because it can travel farther than direct current.

The standard frequency for AC power is 60 Hz (or 60 cycles per second) in North America and 50 Hz in Europe and many other countries.

Alternating current is mainly produced by a device called an alternator, which works by spinning a wire loop to create the waves of AC current. The spinning movement generates the alternating characteristic of the AC power since the current changes direction every time the wire spins from north to south poles in the magnetic field.

The AC voltage can also be easily scaled up or down through a transformer. This makes alternating current highly flexible to meet the electrical needs of different devices.

Applications for AC Power

As mentioned above, most household electronics are powered through AC current, and the same can be said for businesses and offices. Some common applications for AC power include:

• Large appliances like refrigerators, air conditioners, and washing machines
• High power and long-distance transmissions
• Power distribution
• Electric motors
• Industrial equipment

Generally, AC power is the dominant electrical current used in the market since it can be used to produce generators, motors, and power distribution systems. It also costs less to operate, thus being the ideal power source for national grids.

What is Direct Current (DC)

Thomas Edison developed direct current (DC). Contrary to alternating current, direct current is a type of current that flows in a single direction, which means its polarity and magnitude do not change over time.

Since the polarity and magnitude are constant, the frequency of the current is zero.

Direct current can come from sources like batteries and fuel cells, or it can be produced from alternating current through a process called rectification.

The latter is done with a rectifier, a device that converts AC power to DC power by straightening the direction of the current so that it only flows forward.

Applications for DC Power

While DC current cannot travel as far as AC current does, its advantage is that it offers more consistent voltage delivery, which makes it a more ideal option for some applications. These include the following:

• Electronic vehicles and hybrid cars
• Small electronic devices and gadgets
• Flashlights and batteries
• Solar panels
• Radios, laptops, and cellphones

Essentially, all devices that run with batteries or use an AC adapter or USB cable are powered by direct current. The consistency in DC voltage makes this type of current a better choice for most smaller consumer electronics.

Moreover, the increasing popularity of solar panels, LEDs, and electrical vehicles has also spotlighted new advancements in DC power.

AC vs DC Current – Which is Better?

The main difference between AC vs DC is the direction in which the current flows and the difference in voltage control.

• For DC power, the current flows forward in a single direction with consistent voltage.
• For AC power, the current periodically changes direction and the voltage can be varied using a transformer.

In terms of application, AC power is more suitable for larger power generation and distribution, making it the source of electricity for outlets in homes and buildings.

On the other hand, DC power has a smaller range of use cases, focusing more on low voltage and low current applications like electronic devices.

Overall, one is no “better” power source than the other when we look at alternating current vs direct current. Both are equally important as each are ideal for different circumstances.

While AC seems to perform better in many aspects, such as cost, reach, and flexibility, its flow is not as smooth and voltage not as consistent as DC. As such, a better way to think of it is that the two types of currents co-exist to make our lives a lot easier.

Finding the Right Power Supplies

Understanding the difference between AC and DC current allows you to find the right power supplies you need for your appliances and electronics. Using the wrong type can risk damaging your electrical devices, so you need to ensure that you have the proper supplies with the right voltage and type of current.

If you are unsure about what you should get, you can contact our experts to help you out.

About Premium Electric

Don’t try to do electrical work yourself. No matter what type of electrical problem you may have, to keep yourself and your loved ones safe, always hire a certified electrician.

At Premium Electric all our electricians are fully certified and highly experienced.

Need A Residential Electrician?

No matter where you are in the Fraser Valley or the Vancouver Lower Mainland, we can help you with any type of residential electrical problem you may have.

We also do electrical installations so if you need a licensed electrician in Chilliwack, Mission, Abbotsford, Langley, or Maple Ridge, please contact us. 

Need A Commercial Electrician?

If you need leasehold improvements or a commercial electrician for installations, repairs or maintenance, we have a lot of experience in these areas as well and have serviced clients in Surrey, Burnaby, and Poco/ Coquitlam.

For more info, see our earlier post entitled, What Do Electricians Do. All our electrical work is guaranteed and fully insured.

Contact Premium Electric

Do have more electricity questions? Want to know more about AC vs DC current or do you need an electrician?

Please let us help. Give call us at 604-308-6195, send us an email, or complete our online contact form.

We look forward to not only meeting but exceeding your expectations!