May 3, 2022

What is Bidirectional EV Charging?


5 Min. Read

Bidirectional charging is a relatively new benefit of electric vehicles (EVs), but it’s intriguing, transforming your EV into a home power source and a way to save money. Going bidirectional can save or even make money while benefiting the environment and ensuring additional peace of mind in a power disruption.

While still not widely available, the technology makes it possible to transform your EV into a giant battery pack on wheels that can store cheap electricity. You can access that electricity to reduce your usage of more expensive power during an outage. This blog explains what bidirectional EV charging is and what’s in it for you.

Bidirectional EV charging basics

Usually, the power to appliances goes one way, from the outlet to the power item. The same has largely been true when EVs are plugged in; the power goes from the charging station to the vehicle’s battery. However, as the name implies, bidirectional charging offers a two-way power exchange: power goes into the car but also, when needed, is discharged from the vehicle to your house (V2H) or the grid (V2G).

Unlike standard EV charging stations, a bidirectional EV charger, simply put, sends energy to and from an EV battery. The reality is more complex, with the charger functioning as an inverter taking the alternating current (AC) and converting it into direct current (DC) and vice versa. Bidirectional chargers are more sophisticated and expensive than routine ones, and very few EVs already on the market can use them. However, their potential has been proven. In fact, the Nissan Leaf was established as a potential charging system in Japan due to the country’s 2011 earthquake and tsunami. Ford has touted home backup power with its new F-150 Lightning EV pickup, while the Hyundai Ioniq 5, Kia EV6 and other CHAdeMO vehicles can already transfer energy bidirectionally.

Power production on wheels

How much backup power can an EV produce? While electric consumption varies by state and weather conditions, the average daily U.S. consumption is 32 kilowatt-hours. Newer EV batteries can hold approximately 60 kWh, powering households for about two days. The Ford F-150 Lightning has about 98 kWh, which could power a house using regular consumption for three days, or much longer if the electricity is rationed.

Besides using an EV and charger with bidirectional abilities to power your home, you can also use the technology to send power from your EV back to the grid. This concept is already in use with off-grid systems for solar power, which contain a bidirectional inverter-charger. Used cars and solar panels might also be able to serve as “peaker” energy to boost grid capabilities when power demand is high.

V2G capabilities are being tapped in Europe and Asia, and the technology is growing. For example, a Volkswagen exec boasted that the company’s EV fleet, which will soon include cars with bidirectional capabilities, could hold (and provide) more power than the world’s hydroelectric plants by 2025.

Bidirectional EV charging benefits

VW is not the only business enthusiastic about the future possibilities of two-way EV charging. Various firms, municipalities and homeowners are already taking advantage of these capabilities, or are planning to. For example, the Newlab technology center in Brooklyn has a Volkswagen Leaf that sits in the parking lot all day to help power the building. They use software to monitor their consumption of electricity. When demand reaches a particular threshold, the system pulls power from the car to avoid using more expensive energy.

Let’s look at four clear benefits offered by two-way charging:

  1. Financial

Whether you are a homeowner or manage a fleet, you can use the technology to save money. Where utilities have time-of-use electric pricing, an EV can be used for “peak shaving”. That involves using cheaper nighttime electricity to charge the EV and store electricity for use during the day, when power costs more.

This allows you to avoid using power from the grid and reduce electricity costs. For businesses, a bidirectional strategy can help you power your building and even let you take advantage of energy credits or other incentives by reducing daytime usage.

  1. Environmental

Owning an EV already offers benefits by eliminating the use of fossil fuels to power the car. This is especially true if you employ rooftop solar panels with newer technology to charge your vehicle. You can further the positive environmental effect with two-way charging by reducing your dependence on the power grid. You no longer need to worry about power shortages caused by weather and natural disasters.

For cities and states that have pledged to convert to renewable energy, public- and private-sector EV fleets parked by late afternoon could feed power into the grid during the peak demand period each evening.

  1. Psychological

A reliable source of backup power can be a huge relief in weather-related outages. The Texas freeze, California fires, hurricanes in the South and superstorms have wreaked havoc on power lines, creating multi-day outages. Many people purchased generators to keep their fridges or other essential appliances running. Knowing that you can pull power from your car is a huge relief.

  1. Grid managerial

As more EVs and charger stations have bidirectional capabilities, there could be significant improvements in power management as EV owners impact grid load. Power surges, a need for more “peaker” power plants and other grid demand issues can be avoided or better managed. Two-way charging capabilities will also help mitigate concerns about having enough power for the country to migrate to EVs.

There will be a need for new policies given the number of utilities involved (approximately 3,300). For power companies, which are eagerly encouraging EV purchases, expanding two-way power capabilities will need to be factored into their strategic planning, much like they did with solar panels, to better understand how customers may take advantage of the possibilities and the impact on the grid.

Graphic with EV and charging station, sign up for free quote with Qmerit

#1 Trusted Bidirectional EV Charger Installer

As the largest network of certified EV charger installers in North America, Qmerit is the most trusted EV charger installation partner recommended by automakers, EV charger manufacturers, utilities, businesses, and homeowners alike.

But don’t just take our word for it. Rated #1 in customer satisfaction, Qmerit’s experienced network of certified electricians has installed more than 450,000 EV charging stations in homes and businesses across the U.S. and Canada!

Give us a call at (888) 272-0090 or complete our online EV assessment to find out why we’re North America’s most trusted EV charger installation service provider today!

Author: Lowry Stoops

Lowry Stoops

President, Qmerit Network