Do USB Sockets Draw Power When They’re Not Being Used?

Installing USB sockets allows us to make full use of smartphones, tablets, and other modern devices at home. They let us do anything from transferring data to charging gadgets overnight. The downside is that USB sockets do draw power when not in use, unlike an unused outlet. This idle current as it’s called amounts to only a few cents of electricity per year.

The reasons USB sockets continue to draw power include:

  • LED Indicators: These indicators use electricity so it’s impossible to avoid a current draw, but this isn’t enough to cause safety issues.
  • Chargers Left in the Socket: A charger left plugged in is easier to access, but can draw more power (in certain conditions, a short circuit can occur).
  • Devices Left Plugged In: Every USB device requires electricity to communicate with other USB devices unless you disable this feature.

Do All USB Sockets Draw Power?

By their inherent design, yes. However, some sockets have a switch. By flipping this switch off, the USB socket will be disabled and won’t draw any power. Spring-loaded doors on some USB sockets close when a device isn’t plugged in, preventing an unused socket from consuming electricity.

Even a USB port in a vehicle draws some power. If you leave a device plugged in overnight, it can take a little power from the battery, but won’t completely drain it. It doesn’t use enough electricity. Nonetheless, some vehicles turn USB sockets off when the engine isn’t running.

How Much Power Does an Idle USB Socket Draw?

A USB charger draws about 0.05W when nothing is plugged in. By comparison, a 60W light bulb will use 60W of electricity, so a USB outlet uses very little power. The type of outlet matters as well. A USB 1.0, 1.1, or 2.0 outlet uses 0.5A of power while a USB 3.0 unit uses 0.9A and a USB 3.1 outlet uses 3A. The more amperage an outlet supports, the faster it can charge a device, depending on its requirements (smartphones need just 1A while tablets need 2.1A).

Do USB Cables Draw Any Power?

By itself, a USB cable draws very little power. The cable must be plugged into a USB port or charger to work, which is what determines how much electricity is drawn. Aside from drawing power, a USB cable is usually safe to leave plugged in. This is not likely to cause equipment damage. USB sockets are also extremely safe to use unless they are of poor quality. A cheap outlet, just like any electrical outlet, can overheat; at the very least, it can take longer to charge devices.

Don’t Let Power Draw Prevent You From Using USB Sockets

When you wonder, “Do USB sockets draw power?” The benefits outweigh any disadvantages. A USB socket can charge your phone faster than any computer will, and it won’t overload the device or ruin its battery. It is also more compact than most adapters, which can be bulky and take up valuable space. 

You can also charge different devices with the same cable. And since you can install as many USB sockets as you need and still not use a significant amount of power, mobile devices can be charged anywhere in your home. Aesthetically, USB sockets don’t impact home decor; in fact, they generally tend to blend in.

Can I Install a USB Socket Myself?

A USB socket is an electrical receptacle, so requires some wiring work to install. What an individual with no experience should ask, instead of “Do USB sockets draw power?”, is “Should I call an electrician to add USB sockets?” At Express Electrical Services, our licensed technicians are trained in the latest tools and products, so can install USB sockets quickly and safely. We can also install GFCI outlets, new switches, and circuit breakers as well as rewire your home

Let us know what you need and our 24-hour electrician can install or repair any outlet or switch in your Southern California home. To begin, contact us online or call 323-727-7799.