How Much Energy is Lost When Charging an Electric Vehicle Battery?
13th September 2024
How Much Energy is Lost When Charging an Electric Vehicle Battery?
Discover the energy loss involved in charging electric vehicle batteries. Learn how different models compare and the factors contributing to energy inefficiency.
Understanding Energy Loss When Charging Electric Vehicle Batteries
As the world shifts towards electric vehicles (EVs), many consumers are focusing on how efficiently their cars use energy. While diesel and gasoline engines are known for thermal inefficiency, electric cars face a similar challenge during the charging process. Significant energy is lost between plugging in and storing power in the battery. Understanding this loss is key to evaluating the overall efficiency of electric vehicles.
Measuring Energy Loss: Insights from German Automobile Club (ADAC)
The German Automobile Club (ADAC) conducted tests to measure how much energy is wasted when charging various electric vehicle models. On average, 14.56% more energy was used than what actually ended up in the battery. These tests were conducted under controlled conditions using a 22 kW wall charging box at a temperature of 23 degrees Celsius. While no vehicle is immune to this inefficiency, the results varied significantly across different car models.
Electric Vehicles with the Least and Most Energy Loss
Among the tested vehicles, Volkswagen’s ID models emerged as strong performers, with an energy loss of just over 8%. This is considered an excellent result, showcasing the potential for efficient charging. On the other hand, the Mini Cooper SE had the highest energy loss, with nearly a third of the energy lost during charging—a concerning figure for those prioritizing efficiency.
In Sweden, the popular Volvo XC40 exhibited a charge loss of about 20%. While this is not as high as the Mini Cooper SE, it still reflects a significant inefficiency. The BMW iX, with a net battery capacity of 105 kWh, required 125.2 kWh to fully charge, meaning 20 kWh of energy was lost in the process. For owners of cars with large batteries, this loss is financially significant as well.
The Root Cause: Why Energy is Lost During Charging
The primary reason for energy loss during charging lies in the conversion process. Electric vehicles rely on alternating current (AC) from the power grid, but batteries can only store direct current (DC). The conversion from AC to DC results in energy being lost along the way.
Many electric car owners tend to focus on energy consumption while driving, unaware of the significant loss that occurs during charging. However, these differences in charging efficiency can play a crucial role in determining the overall cost of owning and operating an electric vehicle.
Why Charging Efficiency Matters
For those with larger batteries, the energy loss can be substantial, as demonstrated by the BMW iX. In the long term, inefficient charging leads to higher energy costs. As electric vehicles continue to grow in popularity, understanding and minimizing these losses will be essential for improving both the cost-effectiveness and environmental benefits of EV ownership.
Conclusion: Energy Efficiency in Focus
While electric vehicles are a key solution to reducing emissions, energy loss during charging presents an ongoing challenge. Car manufacturers and charging infrastructure developers must continue to work on minimizing these losses to maximize the potential of electric vehicles. Consumers, too, should be aware of these inefficiencies when evaluating which EV best meets their needs.