Electric Vehicle Wireless Charging

1. Problem: Electronic Vehicle Wired Charging   

The lack of public charging options creates range anxiety that prevents internal combustion engine car drivers from buying an electric car. Electric vehicle charging with a cable generates friction when outdoors in cold or wet weather. Although the J1772 electric vehicle charging standard is gaining widespread adoption, driver must still make sure each charging station works with their car. Public charging stations increase street furniture in communities. Traditional public charging stations deployment can create trip hazards for pedestrians. 

2. Solution: Electronic Vehicle Wireless Charging

Wireless Electric Vehicle Charging Systems (WEVCS) reduce friction for drivers by preventing the need to plug in. Wireless charging also reduces street clutter and the hazard of tripping over cables. Once a driver parks above a charging pad, the car starts charging via resonant magnetic induction. Automakers and suppliers have agreed on a wireless power transfer (WPT) standard to charge electric and plug-in hybrid vehicles. SAE International develops and promotes standards for the aerospace, commercial vehicle and automotive industries. In November 2020, the SAE J2954 inductive charging standard was accepted by car manufacturers. Key features include:

— Wireless signals sent between the car and charging system to initiate and stop charging.
— A charging pad that is about one square meter and receiving pad integrated under the car. 
— Enabling increased interoperability between hardware and software across manufacturers.
— Achieving 94% efficiency compared to wired connections ranging from 3.3 to 20 kilowatts.
— The potential to enable autonomous cars to charge themselves without human interaction.

Wireless Charging Companies:

— Witricity provides 3.6kW to 11kW wireless charging from in-ground placements in asphalt and cement with foreign object detection, live object detection, and position detection.
— Plugless Power provides 3.3kW and 7.2kW wireless EV charging stations. Purchase of the charger includes hardware and installation to upgrade an EV for wireless charging.
— Wave provides fast wireless EV charging for buses with deployments up to 250kW.  

Dynamic WEVCS is a potential future technology to charge electric vehicles while driving by embedding roads, such as highway sections, with charging transmitters.

3. Stakeholders

The stakeholders in the wireless charging ecosystem include: 

Wireless Charging Providers: Witricity, Plugless Power, Wave and other providers. 
Car Manufacturers: BMW, Honda, GM, and Nissan are all Witricity development partners.
Consumers: Drivers must buy future cars with EV wireless charging capabilities. 
Real Estate Owners: Public and private site owners must approve wireless charging sites. 
Utility Companies: Energy distributors must support standards and interconnection to the grid. 
Policymakers: Politicians must generate policy that allows wireless charging deployment. 

4. Implementation

It  remains questionable if wireless charging will be implemented and deployed at scale. Cost and deployment hurdles must be solved in order for wireless charging to gain traction. Wireless charging requires: 

1. Refinement of wireless charging systems to provide auto manufacturers confidence to deploy this technology. 
2. Wireless charging pilots with public and private partners to get support for widespread deployment. 
3. Assuming barriers are overcome, each site will require approval from public and private real estate owners. 
4. Once a site is confirmed, ground pads will require utility companies to confirm interconnection requirements. 
5. Upon gaining utility approval, ground pads will require permitting, leasing, provisioning, and construction. 
6. The wireless charging system can then be installed. 
7. Drivers can then gain the benefits of wireless charging. 
8. The wireless charging system will then require operating and maintenance by the provider. 


Sources:

— Wireless EV charging gets a boost: https://www.greencarreports.com/news/1130055_wireless-ev-charging-gets-a-boost-single-standard-will-harmonize-systems-up-to-11-kw
— Wireless Charging Can Boost Acceptance of Electric Vehicles https://passive-components.eu/wireless-charging-can-boost-acceptance-of-electric-vehicles/
— Witricity https://witricity.com
— Plugless Power: https://www.pluglesspower.com
— Wave Bus Charging: https://waveipt.com