Imagine parking your electric vehicle, walking away, and returning to a fully or partially charged battery. Wireless EV charging is being developed, and while it may sound like a dream, it is a reality. Moreover, the concept is promising because it makes charging more convenient for drivers by eliminating the need to fumble with cords to fuel EVs. So how does it work?
Wireless charging for electric cars transfers energy from a charging station to the vehicle without a physical connection. The charging station generates an electromagnetic field, which a receiver on the car picks up and converts into electrical energy that charges the car’s battery.
The choices for wireless chargers have grown multi-fold with the increase in phones that support functionality. So what is wireless charging, what advantages could EVs gain from wireless charging, and what disadvantages does wireless charging provide? Let’s find out.
Can You Charge an Electric Car Wirelessly?
You can charge your electric car wirelessly. However, your EV must enable wireless charging for you to do so.
Similar to how not all phones supported wireless charging right out of the box when the technology was first rolled out, not all EVs come equipped with wireless charging when they leave the factory showroom.
Although some automakers have tested wireless charging in their vehicles, these pilot projects have only been made sporadically available.
The Genesis GV60 is the first car to have wireless charging built in at the factory. As part of a pilot program, South Korean vehicle versions come with this feature. In addition, Hyundai built this tech into its E-GMP platform for dedicated electric vehicles, so you can expect to see it in more models and markets soon.
In China, FAW’s Hongqi brand and IM Motors, a joint venture between China’s SAIC Motor and the e-commerce giant Alibaba, have just started using this technology in their electric vehicles. It is also in the Zhiji L7, which Alibaba backs.
There have been wireless charging add-ons for years, most notably from Plugless Power, which has made a system for the Tesla Model S. WiTricity is also working on a design for the Tesla Model 3.
But because wireless charging is currently only available through third-party hardware, having a wireless charger installed on your vehicle represents an additional expense in addition to purchasing the car.
In cases where wireless charging is optional, it will cost extra. Installing a wireless charging pad in your home also costs extra, although that hardware can be plugged into the same type of outlet as a regular home charger.
How Does Wireless Charging Work?
Wireless charging systems consist of two components. First, the vehicle and ground subsystems make up the wireless charging system. A receiver pad and an electronics module comprise the vehicle side of the wireless charging system.
The ground side of the system consists of a charging pad installed in the pavement, which is connected to an electronics cabinet. Instead of cables, a wireless system requires charging pads that EVs park on top of to power batteries.
Wireless charging, or inductive charging, uses an electromagnetic (EM) field to convey energy between two objects—in this case, the charger and the car.
The charging process begins simply by parking or aligning the vehicle to the wireless charging pad in the ground. Charging can start as soon as the emitting and receiving coils are in alignment.
The procedure is similar to that of a wireless smartphone charger in your car, albeit on a larger scale. Wireless EV charging necessitates using an induction coil, which generates an alternating electromagnetic field from the charging station.
Meanwhile, after the system converts the EM fields to electric currents, a second induction coil receives the EM field from the charging pad, successfully recharging the vehicle batteries.
Wireless charging can be reduced to four main technologies:
- CWCS: Capacitive Wireless Charging Systems
- IWC: Inductive Wireless Charging System
- PMWC: Permanent-Magnetic Gear Wireless Charging System
- RIWC: Resonant-Inductive Wireless Charging System
Because wireless charging is still in its early stages, with most trials taking place on taxis and buses, there is little information on how fast it works in a domestic setting.
Wireless charging can recharge the battery in the bus in about 10 minutes, allowing it to run for 16 or 17 hours without needing a full charge.
As with any new technology, there are differing views on whether wireless EV charging is as effective as standard EV charging.
Wireless charging is currently in the 90% to 93% efficiency range. This means it transfers electricity from the charger to the car’s battery just as standard charging does—and since no charging rate is 100% yet, that’s pretty good.
What are the Advantages of Wireless Charging?
There are many advantages to wirelessly charging EVs. They include:
It is entirely hands-free. Human intervention is not required. You park the vehicle over the charging pad, and charging begins automatically, with the parameters schedulable and controllable via a smartphone app.
Wireless EV charging technology is more interoperable, convenient, and challenging to vandalize than standard public charging stations.
You never have to leave the EV to deal with different connectors, hefty cables, or a not-so-friendly user interface to make payments.
The EV charging process has been simplified, providing a far better end-user experience. First, the driver aligns the automobile with the transmitter pad on the ground for rapid charging.
With charging stations, there is a risk of forgetting to plug in the automobile and starting it. However, wireless charging does not pose this risk because there is no physical connection.
EVs can be charged irrespective of the connector compatibility with the mutually compatible wireless charging system.
Wireless charging increases the number of options for autonomous features such as auto parking. When the car is fully charged, it will automatically transfer to another vacant parking space and allow other automobiles to charge there.
The ease of wireless charging encourages people to invest in electric vehicles, which helps improve local air quality while reducing noise pollution and carbon emissions.
What are the Disadvantages of Wireless Charging?
While wireless charging is quite advantageous, there are a few drawbacks. They include:
- High Cost: Even though this technology is still in its early stages, wireless charging is still more expensive.
- Less Efficient: The charging process is inefficient, so much energy is lost for each car. So, if many people use these wireless charging stations, a lot of power will be lost.
- Low Charging Capacity: It has a low charging capacity compared to the current cable charging technology.
- Dangerous: The strong electromagnetic field could be dangerous for people nearby. This field also makes the other electronic devices around it work less well.
- Tough to Design: Induction technology makes it hard to design and build power electronics because it transfers power.
- Extra Weight: To make the wireless feature work, the wireless feature will add weight to the electric car. This is because the car needs an adapter for wireless charging to work.
Will Wireless Charging Replace Charging Stations?
With so many benefits on offer with wireless charging, it is easy to see why it is set to be the next significant upgrade for EVs.
That said, when the upgrade will happen is another question entirely. While some believe it will manifest soon, others suggest that the technology needs more time.
In the coming years, EVs are expected to take center stage in the automotive industry, but charging them can be frustrating, especially on long drives where adequate planning is required to ensure the battery doesn’t die in a remote area.
Wireless charging at good power and efficiency levels will never be super cheap. Many people will not be willing to spend a few thousand to avoid the pain of spending 10 seconds plugging their car in. Some will—some won’t.
Just like some people still use pay phones despite the advancements in the telephone industry, it is safe to assume wireless charging will only replace charging stations partially.