Frequently asked
questions
General
WiTricity's patented magnetic resonance technology enables the highly efficient transfer of power over the air between a Ground Assembly (GA) transmitter pad and a Vehicle Assembly (VA) receiver pad mounted on the underside of an electric vehicle without any physical connection.
Resonant coils – Both the vehicle assembly and ground assembly have conductive coils tuned to the same resonant frequency, much like a radio tuned to pick up a specific station. Once a wirelessly equipped vehicle is parked over a charging pad, charging begins automatically. AC power from the grid is fed through sophisticated power electronics and sent to the ground assembly pad, where it flows through the coil, generating a magnetic field. This magnetic field oscillates at the resonant frequency of the vehicle and ground assembly pads.
Energy transfer over the air – Unlike a wireless phone charger, which requires the charger and the device to be very close together, the vehicle assembly captures the oscillating magnetic field from the ground assembly pad over a significant air gap, which can range from 3 to 8 inches.
Conversion to electricity – AC voltage is induced in the receiver coil on the vehicle assembly, which is then converted to DC and sent to the battery to create power.
Magnetic resonance delivers wireless power over an air gap, scaling from Level 1 to DCFC kilowatt levels. There are four major advantages: spatial freedom, multiple devices powered by a single source, the ability to power through surfaces, and scalable power transfer. See why magnetic resonance is the only technology that meets automaker requirements for wireless charging.
Inductive charging technology, like that used in mobile phones, requires the transmitter and receiver to be in close contact and with perfect spatial alignment. In addition, the efficiency is relatively low. Magnetic resonance charging is very forgiving. It allows power transfer over distance with greater spatial freedom, so the vehicle doesn’t have to be perfectly aligned with the charging pad for the system to work.
The use of resonance, cutting-edge power electronics, and clever control algorithms is why WiTricity's systems provide 92% grid-to-battery electrical efficiency, matching that of most plug-in charging systems.
WiTricity's technology can be engineered to meet the requirements of many use cases, including neighborhood electric vehicles (NEVs), cars, trucks, and buses. The distance over which a system can transfer energy depends on the size of the resonator coils and the application efficiency requirements, but in general, the air gap is 3 to 8 inches. Most passenger vehicles, from sports cars to SUVs and pick-up trucks, fall in that range.
Yes, WiTricity can transfer power through ice, snow, and also asphalt and cement – with no loss in electrical efficiency.
WiTricity was instrumental in helping to develop and harmonize international standards through its leadership and participation in industry groups including SAE International (Global), IEC/ISO (Global), DKE (Germany), and CATARC (China). We continue to help lead the effort to ensure standards for all aspects of wireless charging. Learn more here.
I’m interested in wireless charging for my fleet
WiTricity wireless charging is being developed for NEVs, passenger cars, and fleet applications.
The best way to determine the benefits of wireless charging for your electric fleet is to work with us to develop a pilot. You’ll find that, unlike plug-in chargers that require time-consuming, hands-on labor, clutter the ground, and require excessive maintenance, WiTricity’s ruggedized charging pads add power to battery-electric vehicles quickly and automatically during scheduled stops and overnight dwell times. The combined speed, power, safety, and hands-free nature of WiTricity wireless charging is the most advanced way to enable electric trucks to match the range and duty cycle of their legacy diesel counterparts.
Wireless charging is free of cables and moving parts, so there is nothing to trip over, run over, break, or freeze. This ensures risks to workers are minimized while revenue-generating operational uptime is maximized.
For many common applications, the cost of ownership calculations show that wireless provides significant savings over legacy plug-in charging. Much of these savings come from a system that is fully automated, has no moving parts, and can be deployed in already cramped depot spaces or highly trafficked areas – all of which enables successful electrification at a lower cost. Contact us for a custom TCO calculation.
Wireless charging allows vehicles to charge automatically during scheduled stops, such as loading/unloading or rest breaks. Being a fully automated, park-and-charge technology, wireless charging can happen more frequently during the day without interrupting a truck or bus operator’s primary tasks. With a small footprint, the systems can be deployed more easily in more places, making charging more readily available. This means, in certain applications, wirelessly charged vehicles can run charge-neutral, meaning their state-of-charge at the end their days can be the same as it was at the beginning.
The large batteries required for certain bus and truck duty cycles add to the cost and weight of already expensive MHD EVs. Fast and automated wireless charging during scheduled breaks keeps BEVs charged throughout the day and reduces the need for larger batteries.
Wireless charging is free of cables and moving parts, so there is nothing to break or freeze. In addition, vandalism is reduced since there’s nothing to steal.
If transitioning from ICE to electric, wireless charging minimizes the impact. Automated and hands-free, wireless charging has no mechanical contact or human intervention required. This means that charging opportunities are maximized without the need to add manual labor or remove vehicles from operational duty to be charged. Vehicles charge throughout the day, minimizing downtime and lost revenue opportunities.
Yes, our latest generation of wireless charging does provide V2G/V2X capabilities.
WiTricity wireless charging can be seen in multiple scenarios in these videos:
There will be limited availability in 2025 on our current orders. WiTricity will be shipping in quantity to meet your zero-emission plans in 2026 and beyond.