E-Auto: So funktioniert bidirektionales Laden! | Unter Strom – Einfach Elektromobilität | 36 | ADAC

Summary

The video script explores the concept of bidirectional charging for electric vehicles, a technology allowing cars to both receive and supply electricity. It explains three levels of complexity: Vehicle to Device, Vehicle to Home, and Vehicle to Grid, detailing how each works and their potential applications. The discussion touches on the practicality, current research, and future possibilities of using electric cars as mobile energy storage units, contributing to the energy transition and grid stabilization.

Takeaways

• 🔌 Bidirectional charging allows electric vehicles (EVs) to both receive and supply electricity, enabling them to act as mobile energy storage units.
• 🚗 There are three main levels of complexity for bidirectional charging: Vehicle to Device, Vehicle to Home, and Vehicle to Grid.
• 🔌 Vehicle to Device (V2D) involves the car operating in island mode, supplying power to devices or appliances via an adapter connected to a Type 2 plug.
• 🏠 Vehicle to Home (V2H) connects the car to the home's electrical grid, using the car's battery as a storage unit for solar power, charging during the day and supplying the house at night.
• 🌐 Vehicle to Grid (V2G) enables the car to feed electricity back into the public grid, helping to balance grid fluctuations and potentially earning money through the provision of ancillary services.
• 🔄 The transition from DC (direct current) used in EVs to AC (alternating current) used in homes requires a converter, and synchronization with the grid frequency is necessary.
• 🛠️ For V2H and V2G, an intelligent energy management system is needed to determine the amount of electricity that can be supplied to or drawn from the grid.
• ⚙️ Manufacturers are developing compatible devices following a standard set in 2022, which will enable more widespread adoption of bidirectional charging.
• 💰 The cost of DC wallboxes, necessary for V2H and V2G, is currently high, making them less attractive for everyday home use.
• 🛡️ Legal and regulatory adjustments are needed to account for the origin and tax treatment of electricity supplied to the grid or used in homes.
• 🔋 The potential for faster battery degradation and different warranty conditions due to bidirectional charging is a consideration for manufacturers and consumers.
• 🌟 The use of EV batteries as mobile storage could significantly contribute to the stabilization of the power grid and the provision of ancillary services, supporting the energy transition.

Q & A

What is bidirectional charging and why is it significant?

Bidirectional charging is the exchange of electrical energy in two directions. It allows electric vehicles (EVs) not only to receive power for their traction battery but also to supply power to other consumers, such as household appliances or the power grid. This capability is significant as it can contribute to energy efficiency and grid stabilization.

How does Vehicle to Device (V2D) or Vehicle to Load (V2L) work?

Vehicle to Device or Vehicle to Load is the simplest form of bidirectional charging. The EV operates in island mode, disconnected from the power grid, and can supply power through an adapter connected to a Type 2 socket to power electrical devices, such as a vacuum cleaner or to provide electricity to a garden shed or a mobile home.

What is the maximum power that can be supplied through a V2D or V2L setup?

The maximum power that can be supplied through a V2D or V2L setup is dependent on the vehicle's capabilities, but in the script's example, it is mentioned as 3.7 kW.

How can an EV help another EV with low energy through bidirectional charging?

An EV can help another EV with low energy by providing a power donation through bidirectional charging. This requires a bidirectional onboard charging device and an adapter that can supply power from the Type 2 connector to another EV.

What is Vehicle to Home (V2H) and how does it differ from V2D or V2L?

Vehicle to Home (V2H) is a bidirectional charging method where the EV is connected to the home's power grid. The EV's battery acts as a storage unit for electricity from a photovoltaic system, charging during the day and supplying power to the house at night. This differs from V2D or V2L as it involves integration with the home's power grid rather than just supplying power to individual devices.

What is the concept of Vehicle to Grid (V2G) and its potential benefits?

Vehicle to Grid (V2G) is the most complex bidirectional charging variant, where the EV's battery can supply electricity back to the public power grid. This allows the EV to participate in the energy network, potentially balancing grid fluctuations and providing ancillary services. Users can also earn money by providing frequency regulation energy.

What are the technical challenges for an EV to supply AC power to a household from its DC battery?

The technical challenge is the conversion of DC power from the EV's battery to AC power used in households. This requires a converter, and the frequency of the AC power must be synchronized with the grid. There are two approaches: using a bidirectional onboard charging device or using a bidirectional wallbox at home that converts and synchronizes the power with the home network.

What is required for an intelligent energy management system in bidirectional charging?

An intelligent energy management system is needed to determine how much power is required in the house (for V2H) or how much power can be supplied to the energy grid (for V2G). It ensures the efficient distribution and utilization of energy based on real-time needs and availability.

How does the new standard set in 2022 impact the development of compatible devices for bidirectional charging?

The new standard set in 2022 provides guidelines for manufacturers of vehicles, wallboxes, and energy management systems to develop and offer compatible devices. This standardization is crucial for ensuring that these components can work together seamlessly in bidirectional charging setups.

What are the considerations for manufacturers regarding warranties and battery lifespan with bidirectional charging?

Manufacturers need to consider how bidirectional charging might affect battery lifespan and warranty conditions. Strategies include limiting the maximum duration or energy amount that can be drawn from the battery or restricting the daily usable energy amount within a specific time window to prevent warranty issues.

What are the legal and regulatory requirements for Vehicle to Home and Vehicle to Grid implementations?

Legal and regulatory requirements for V2H and V2G include demonstrating the origin of the electricity, ensuring tax compliance, and meeting strict standards to prevent disruptions to the power grid. Manufacturers must provide evidence to electricians for grid operator registration, and there is a need for a clear definition of what constitutes a mobile storage unit.

What is the potential impact of bidirectional charging on the energy transition and the use of renewable energy?

The use of EV batteries for bidirectional charging could significantly contribute to the energy transition by providing a massive storage capacity that can help stabilize the power grid and supply frequency regulation energy, thus supporting the increased use of renewable energy sources.

What are the current market trends and predictions for the availability of bidirectional charging solutions?

While the exact timeline is uncertain, there are indications that market solutions for bidirectional charging could become available by 2025. Companies like Volvo have announced models, such as the EX90, that will support both AC and DC charging options, leaving the choice to the consumer.