Wireless charging has become very popular in recent years. Its popularity has grown due to the speed of charging, as well as saving time during the recharging process. Plus, the technology is wireless, which means there’s no need to plug your device into a charging cord.
However, some people are concerned about the proliferation of these devices. Can they increase a person’s EMF exposure? This is a question we’ll review in this article.
Wireless Charging is Great Technology
Wireless charging is very new; this technology was first made popular by Samsung’s mobile phones and then Apple’s iPhones. Wireless charging first appears in different types of devices, including kitchen appliances, power tools, and more.
The great thing about wireless charging is the ability to charge without a power cord. Most of us have many devices, each with its own cord. This means a tangle of cords running across tables, desks, and more. Not only that, but it’s necessary to connect each device to its respective cable. The result is a mess of cables and the hassle of attaching each device to a separate cable. Another issue with wires is that they will eventually break.
This is why wireless chargers have become so popular. They provide more convenience while cutting down on the mess of cables running everywhere. These days, it’s easy to find wireless charging available in hotels, restaurants, cars, and more.
History of Wireless Charging
Wireless charging has been around for a long time. It was first developed back in the late 19th century by Nikola Tesla. He was a pioneer of electricity and developed the use of magnetic resonant coupling. In other words, he learned how to transmit electricity through the air by creating a magnetic field between two circuits. A transmitter and receiver were necessary for this process to work.
At the time, the technology was not very practical. However, with the recent advances in technology, wireless charging has become a useful tool.
How Does Wireless Charging Work?
There are three types of wireless charging. Let’s take a look at each one.
Inductive wireless charging uses a low-frequency oscillating field between 110 and 205 kHz. This type of wireless charging creates an electric current with a magnetic field. To work, the power transfer is done between two non-resonant coils.
When a device with a wireless receiver coil is placed directly on the charging pad (the charging pad has a transmitter coil), the device’s battery charges by intercepting the magnetic field from the charging pad. In this type of wireless charger, the larger the coils, the larger the magnetic field.
Chargers must be placed in a precise manner in order for charging to take place. This can be a downside for magnetic induction charging if the phone vibrates or falls off the pad for some reason. The charging will then case.
Resonant Wireless Charging
This method of wireless charging was developed by MIT (Massachusetts Institute of Technology). They were trying to improve the efficiency of inductive wireless charging. They developed a way to transfer power between two coils operating at the same resonant frequency.
Resonant wireless charging uses a higher frequency oscillating magnetic field of 6 MHz. This method is still inductive; however, it uses both coils’ coupling, which allows the coils to be centimeters apart.
Using this method, multiple devices can be charged at the same time, as long as they are in close proximity to the charger. This means there can be a larger distance between the coils than with magnetic induction wireless charging.
The major problem with resonant wireless charging is that this method has a lower level of efficiency. When devices are placed farther away, they will charge more slowly. Because this method uses higher operating frequencies, it’s possible electromagnetic interference will cause problems with charging, too. And this method puts off more EMF radiation than magnetic wireless charging.
RF Wireless Charging
This is a newer method of wireless charging, which is not generally available to everyone yet. It uses radio frequencies to charge devices. RF wireless charging produces an electromagnetic field, which emits EMF waves (radio frequencies). The energy is sent to the device over these EMF waves, and the device then converts them into energy to charge the device.
This type of wireless charging has the benefit of charging more than one device in a room. However, it also means people will be exposed to higher amounts of EMF radiation too.
EMF Radiation & Wireless Chargers
Of the three types of wireless charging, magnetic induction creates the smallest electromagnetic field. This field is only a few millimeters wide and is between 5-15 watts. When plugged in, this type of charger only puts off very small levels of ELF, with possible emissions up to 3 mG (milligauss) when the phone and the charger coils are aligned.
How does this compare to other electric devices in your home? An alarm clock or a computer monitor emits about five mG, while a standing power line can emit between 5-10 mG of EMFs. That’s definitely a little more than your wireless charger.
According to the EPA, daily exposure to EMFs should be under four mG. Some recommend no more than 2mG exposure each day. The inductive wireless charger is somewhere in between these numbers. This makes the device safe; however, it still adds to your daily exposure to EMFs. So, the device could add to your overall exposure, which could make you experience some health issues.
If you’d like to lower your daily exposure to EMFs, then you can take these steps:
Stick with cords: while more cords are not considered a good thing, they do help to eliminate the source of transmissions of EMFs. And it only takes a couple of seconds to plug your device into to charge.
Using a wireless charger: if you’d prefer to use a wireless charger, then keep this and the devices they charge away from areas of heavy traffic. This means keeping the devices out of the living room, the kitchen, and other areas to lower your exposure.
Keep the technology out of the bedroom: EMF exposure has been tied to sleep disturbance, so keep the wireless charger and other devices out of the bedroom.
Don’t use the mobile device while charging: the device must sit on the charging pad to charge, which means you’d have to be close to the charger to use your mobile device. Instead, commit to not using your mobile device as it’s charging, and you’ll reduce your EMF exposure.
Summing It Up
Wireless chargers can be a great convenience, which includes the reduction of wires. While they’re safe, they still add to a person’s overall exposure to EMFs. So, be sure to stay away from your wireless charger and avoid using your mobile device as it’s charging.
This way, you’ll cut EMF exposure, which lowers your risk of developing associated health problems from EMFs.