Even though electric vehicle charging is new, the technology has rapidly developed in the recent past. What was previously a technology that allowed an electric vehicle to charge fully in 8 hours has now progressed to allowing full charge within 30 minutes. Demand for charging stations has also increased with the growth in the sales of electric vehicles. Either way, electric vehicle charging can be done through cable or wireless.
1) Charging through a cable (Manual plug in charging)
1 – 230 Volts socket (AC) limited to 2.3 kW (1-phase, 10A)
2 – 230 Volts socket (AC) entails charging through In-Cable Control Box (ICCB). 7.4 kW, capacity of max. 7.4 kW can be (1-phase, 32A) or 22 kW (3-phase, 32A)
3 – The adequate charging capacity (AC) is determined by communication between the charging station and vehicle. 11 kW, 22 kW or sometimes 43 kW (>22 kW = fast charging).
4 – DC charging (Fast charging), from 50 kW to 175 kW
2) Charging by means of a pantograph
Charging by pantograph delivers a high transfer of energy in a short time (typically 5-10 mins) through conductive transfer. Heavy-duty vehicles like electric buses, trucks and special vehicles work on pantograph technology for fast charge. There are two types of pantograph charging to deliver power for EVs.
Top down or inverted pantograph
3) Wireless EV Charging (WCS)
Wireless charging systems charge electric vehicles by using electromagnetic field to transfer energy. Wireless charging for electric vehicles can be distinguished into two categories:
a) Static Wireless Charging
Source – Qualcomm
In this type of in wireless charging system, the vehicle gets charged when it is parked (static mode) above the transmitter, with the receiver arranged underneath the vehicle. Importantly, the vehicle receiver needs to be aligned over the transmitter to transmit power through the air gap. Charging time depends on the power supply level, distance (air gap) between the transmitter and receiver, and their sizes.
b) Dynamic Wireless Charging (DWC system)
Source – PTCarretera
In this type of in wireless charging system, the vehicle gets charged while in motion. How it works is that power is delivered from a stationary transmitter to the receiver coil in a moving vehicle. With Dynamic wireless charging systems (DWCS), range anxiety typically experienced by drivers of electric vehicles can be minimized with the continuous charging of its battery while driving on DWCS enabled roads. Further, this type of system removes the need for large battery storage, allowing a steep drop in vehicle weight and improving the overall efficiency as a result.
Electric vehicles typically require many hours for full charging (without high-powered charging stations). However, dynamic wireless charging technology eliminates that requirement by delivering power even when the vehicle is on the move “on the road by the road” and when the vehicle is moving above the path of transmitters.
The advent of wireless charging enables an array of opportunities and new markets, which are yet to rise. From autonomous taxis to cargo transport without halt, innovate transporting methods are possible. Wireless charging EV also allows users to can avoid getting out of the vehicle at extreme weather conditions to charge the vehicle.
Currently, investments are being sought to develop dynamic wireless charging that also allows data transfer between the road and the vehicle, which gives the users access to multiple types of data like entertainment, weather conditions, traffic conditions. The consumer will be billed based on the amount of energy consumed. Smart roads with autonomous driving technology also pave the way for motor homes (trailers attached to vehicles) within a decade.
Governments are now looking forward to building smart roads and investing in the R&D of wireless charging to improve efficiency. Sweden transport administration believes that electric roads are an important contribution to reducing CO2-emissions from heavy transportation (Trucks and buses).
They have commissioned the worlds first smart road that can charge both an electric truck and a bus inductively while in full motion. The EUR 11 million project is developed by ElectReon, which is doing initial tests on a 1.6 km of road with the total project being 4.1 km. DWCS will be tested in multiple seasons to check the durability and efficiency in different weather conditions.
ElectReon says the Swedish government has prepared a project road map for an electrified road. The plan includes the construction of 2,000 kilometers of an electrified road on a high-speed highway for dynamic charging of electric trucks at an estimated cost of USD 3 billion.
The UK plans to spend 40 million pounds in electric vehicle charging infrastructure and wireless charging roads (dynamic charging) to push the country towards better air quality. The government plans to develop both on-street and wireless charging to help transition from internal combustion engine cars to electric and hybrid. The WCS will be installed on residential streets, car parks, and taxi ranks across Greater London, the Midlands and Scotland and will become operational by June 2020.
Source – Qualcomm
Despite the slow progress in the market, wireless charging has several desirable features like it doesnt require a driver to input, and it charges automatically when parked above the charging pad. It is resistant to vandalism and can even be installed underground. There wont be a risk of explosion while charging, as there is no contact with the vehicle. New wireless charging designs have similar efficiency when compared to wired charging.
The OEMs and governments are emphasizing and incentivizing electric vehicle usage and sales to reduce tailpipe emissions. Countries like China are cornering consumers to buy electric vehicles with many schemes and quotas. With the increase in demand for electric vehicles, the requirement for charging stations would increase.
Wireless charging station industry is based on the transmission of energy from a power source to electric vehicles without wires or cables. Wireless charging is a reliable, convenient, and safe technology to power and charge electric vehicles. In addition, with the elimination of physical connectors and cables, the technology is cost-effective and safer and has many other advantages over the traditional charging systems.
The electric vehicle segment will generate the greatest increase in demand for Tx (Transmission coils or Source coil) and Rx (Receiver coil or Load coil) devices. These coil shipments will increase rapidly from 2019 to 2024.
EV companies are investing in wireless charging technology and are enhancing auto parking technology, which allows vehicles to automatically park above the static wireless charging systems (SWCS) to charge when the vehicle reaches home or work. BMW patents an innovative new technology, which allows users to charge their electric motorcycles through kickstands. The kickstand has its own AC coil embedded in the tip, which converts electromagnetic current from the ground pad into electricity thats sent to the motorcycle battery through a cable.
The wireless charging market is dominated by start-ups and large market participants. Some of the key players include Qualcomm Inc., Fulton Innovation LLC, Texas Instruments, Inc., WiTricity Corporation, Convenient Power HK Ltd., Integrated Device Technology, Inc., Energizer Holdings, Inc, Oregon Scientific, Inc.
The way of transportation of people, goods, and vehicles from one place to another will change dramatically over the next decade by technological changes and advancements combined with economic factors and new policies and regulations. Wireless charging plays a critical role in this story, making process of switching to a carbon-free transportation alternative easier, in turn increasing its appeal to consumers.
However, there are also some downsides such as considerable potential energy loss (5% – 9%), and the high cost of the infrastructure, making it uneconomical for many governments and residential consumers (average tesla wall connector ranges at USD 1200 to USD 2000 while the wireless charge costs up to USD 3000 for the same rated power). The initial stages of wireless charging are restricted to densely populated urban areas and limit the consumers to a predefined location. There might (not proved) also be minor health effects due to the long-term exposure of magnetic fields in the case of dynamic charging.
Based on the present situation, the industry moves into the next phase where electric vehicles keep on increasing the market share, forcing the OEMs to meet emission standards. Though ICE vehicles will continue to dominate the market for several years, in the long-term BEVs are set to dominate. As the transition unfolds, ICE vehicles will begin to decline in share from the current 95% of the global level to about half of all vehicles by 2030-2035, with the other half of the market made up of HEVs, PHEVs, and BEVs.
The wireless electric vehicle charging market has a vast potential as the future is dominated by autonomous vehicles, with many countries planning to ban ICE vehicles by 2030 to speed up the adoption of electric vehicles. Huge investments in R&D for wireless charging forecasts a significant decrease in the price of the system with improved charge speed. Some of the huge barriers for the adoption of the electric vehicle such as range anxiety can be solved which by dynamic charging, which shows the future of electric vehicle charging belongs to inductive charging.