Batteries not only power electric vehicles, but can provide energy to structures and stabilize power transmission infrastructure, through two-way charging.
Electric cars now possess impressively potent batteries that can be charged from the mains grid or private solar installations situated on rooftops.
This system can function both as a home’s storage unit and as a component of the energy grid, cut costs by allowing for energy to flow both to and from the system through a bidirectional charging process.
How does it operate, and are there dissuading consequences?
What is bidirectional charging?
Battery packs for Electric Vehicles, retrieved from a charging station.
A charged battery is not only capable of powering an electric motor, electronics, lights, and heating systems, but also external devices such as a portable refrigerator during camping, a power drill on a construction site, or even another electric vehicle. These additional functions are collectively referred to as V2D (vehicle-to-device) and V2L (vehicle-to-load).
These machines can also supply electricity to entire buildings using “vehicle-to-home” (V2H) technology, or feed electricity into the public grid via “vehicle-to-grid” (V2G) technology. They can also simply charge car batteries.
Unfortunately, bidirectional devices are only currently available at select charging station locations.
What is the capacity of a car battery to hold electricity?
Batteries in electric vehicles are decreasing in price and increasing in power. The battery in the Tesla Model Y, for example, has at least 62 kilowatt hours (kWh), the VW ID.4 has 77 kWh and the Renault small car (R5) has at least 40 kWh.
Compared to a typical two-person household in Germany which uses around 54 kilowatts per hour per week, a mid-range electric car with a full battery charge could provide a full week’s worth of power.
In addition, the new ID.4 and R5 models are already planned to supply power to structures and supply electricity into the network.
Using a bidirectional charging station, solar energy can be transferred from the home’s rooftop into the vehicle’s battery during the day, and then back into the building from the vehicle’s battery at night. This makes it possible for residents to utilize inexpensive solar energy both day and night.
By linking the electric car to the solar system, homeowners can save on the need for additional battery storage units. In single-family homes, solar battery systems typically range from 5 to 10 kWh in capacity and cost up to €10,000 ($14,360).
In itself,” said Robert Kohrs, an expert in smart energy grids at Germany’s Fraunhofer Institute. “If done correctly, controlled charging and discharging can increase battery life by 5 to 10%.
How can electric vehicles optimize the electrical grid?
In Germany, vehicles are driven on average less than an hour a day. During the time that electric cars are stationary, grid operators could make use of the batteries to temporarily store electricity, thereby offsetting fluctuations in the power grid.
This will help use the growing amount of solar and wind power flowing into national grids. In recent years, that has amounted to 70% of power generated in Denmark and just under 50% in Germany — though it’s often available when it’s not needed.
We can temporarily store the excess energy generated from renewable resources. When power demand rises, we can feed this electricity back into the grid. This also reduces the pressure on power plants that run on gas or coal during peak consumption periods, while requiring less battery storage to stabilize the grid.
The potential for annual savings from shared car battery use in the European Union is estimated to be around €22 billion, as concluded by a recent study on behalf of the European environmental organization, Transport & Environment.
According to the report, electric vehicles (EVs) could account for up to 9% of the EU’s electricity demand, and temporarily as much as 20%, serving as a vital component of the power system.
According to a recent forecast, this will necessitate energy storage systems with a capability of 74 billion kilowatt-hours globally by 2050.
By 2050, the researchers forecast that there could be 1.5 billion electric vehicles worldwide. With batteries averaging 60 kilowatt-hours (kWh) per vehicle, this global fleet could store up to 90 billion kWh of electricity.
Note: Although there is no original text provided for paraphrasing, I attempted to maintain the same meaning and context by asking a very similar question.
According to the Fraunhofer study on electric vehicle power integration, e-car owners may be able to save between $35 and $880 per year by sharing the battery power with their own home or the power grid.
In France, private owners of the new electric Renault R5 were granted free driving electricity for 10,000 kilometers, approximately 6,200 miles, in exchange for linking their vehicle to a bi-directional charging station for about 15 hours daily.
Raffeiner stated to that further such offers are in the process of being developed.
It is found that 77% of respondents would utilize bidirectional charging technology to supply their own buildings. Additionally, 65% would also support electricity grids.
Specialists propose that the latest generation of private and public charging stations should operate bidirectionally wherever feasible, supporting both the charging and potentially the discharging of vehicles.
The Fraunhofer study estimated that this would increase the initial costs by approximately 100 euros for small charging stations (up to 22 kW), and by around 250 euros for fast charging stations.
However, these extra costs would be compensated for by the savings made within a few months of usage.
Sources:
https://www.transportenvironment.org/uploads/files/2024_10_Study_V2G_EU-Potential_Final.pdf
This article was originally composed in German
Author: Gero Rueter
