What factors influence the fuel consumption of electric cars?
The impact of model and technical features
The technical characteristics of an electric car play a crucial role in its energy consumption. Understanding these factors can help consumers make more informed choices and optimize the use of their vehicle.
Battery capacity
Battery capacity, expressed in kilowatt-hours (kWh), is one of the determining factors in an electric vehicle's energy consumption andrange. For example, a higher-capacity battery generally means greater range. However, larger and heavier batteries can increase the vehicle's overall energy consumption due to their added weight. For example, the Tesla Model S Plaidwith a high-capacity battery has an average consumption of 21.1 kWh/100 km.
Aerodynamics
A vehicle'saerodynamics also influence its energy consumption. A more streamlined shape reduces air resistance, enabling the vehicle to consume less energy to maintain a stable speed. For example, the Tesla Model 3known for its aerodynamic design, has a relatively low fuel consumption of 14.7 kWh/100 km under mixed driving conditions, contributing to a longer range without increasing battery size.
Motorization
The type of electric motor used also affects fuel consumption. Modern electric motors, such as those used in Tesla or Hyundai vehicles, are designed to maximize energy efficiency, converting up to 90% of electrical energy into motion, compared with around 30% for combustion engines. This efficiency translates into lower energy consumption for a given power output.
Also read → Reduce the energy consumption of an electric car: 8 tips
The importance of eco-driving
Eco-driving is an essential practice for optimizing the energy consumption of electric cars. By adopting smoother, more thoughtful driving techniques, drivers can not only increase their vehicle's range, but also reduce its environmental impact. It involves a number of practices designed to minimize vehicle consumption:
- Avoiding sudden acceleration and favouring a gradual increase in speed can reduce energy consumption by up to 20%.
- Anticipate stops by using regenerative braking instead of traditional braking, enabling drivers to recover a significant proportion of the energy used.
- Maintain moderate speed to reduce energy consumption.
What are the benefits?
Studies show show that eco-driving can improve the energy efficiency of electric vehicles by 10 to 25%, depending on driving style and traffic conditions. This translates into extended range and substantial savings on recharging costs. Adopting eco-driving is therefore not only good for the driver's wallet, but also for the planet. By reducing energy consumption, drivers help to reduce overall energy demand and the CO2 emissions associated with electricity generation.
Also read → Eco-driving: definition and how to practice it?
Measuring real consumption and range
Differences between advertised and actual autonomy
The range of electric cars is the key criterion for aspiring buyers. However, it's crucial to understand that actual range can differ significantly from that advertised by manufacturers, due to the testing methods used.
How can we analyze the discrepancy between the figures quoted and actual performance?
Manufacturers use the WLTP cycle to estimate the range of electric vehicles, as it is considered more representative of real-life driving conditions than the old NEDC (New European Driving Cycle). However, even the WLTP cycle can be subject to deviations. For example, one study revealed that the actual range of an electric car on the freeway at full speed can be 50-60% less than the advertised WLTP range.
Examples: The Renault Zoë e-Tech claims a range of 390 km, but in reality offers only 220 km in real-life freeway conditions. The Tesla Model 3although advertised with a range of 560 km, achieves just 388 km in actual use.
What influence do test conditions have on results?
The WLTP cycle integrates different driving scenarios, including :
- average speed,
- stops,
- speed variation.
However, it has been produced under laboratory conditions which may not perfectly reflect real-life driving conditions, such as the type of roadroad driving styledriving weather conditions and vehicle load. These factors can all have a negative impact on actual range compared with that tested in the laboratory.
Outside temperature also plays a significant role in the performance of electric vehicle batteries. Low temperatures can reduce an electric car's range by between 20% and 40 due to reduced battery efficiency.
Knowing these differences is essential for drivers and future buyers of electric vehicles, as it enables them to better predict range based on their daily needs and expected driving conditions.
Also read → Electric car battery autonomy: where are we?
What measurement tools and methods are available?
To accurately measure the range and consumption of electric vehicles, several tools and methods are used, ranging from mobile applications to advanced technological devices. These tools help users to obtain more reliable data on their electric vehicle's performance in real-life conditions.
| Tool | Main function | Benefits | Example of use | Note |
|---|---|---|---|---|
|
Mobile applications
|
Real-time monitoring of energy consumption and location of charging stations |
Easy to use, provides interactive, real-time updates, often free of charge |
Users tracking their consumption during a journey, planning long-distance recharges |
Ideal for regular drivers who want to optimize their recharging stops |
|
Battery management systems(BMS) |
Continuous monitoring of battery status and precise calculation of remaining autonomy |
Direct integration into the vehicle, providing precise data on battery health |
Drivers analyze battery performance to maximize range |
Essential for long-term battery maintenance and damage prevention |
|
OBD2 scanners |
Read vehicle management data via OBD2 port for in-depth diagnostics |
Provides technical details on vehicle operation, enables advanced customization |
Technicians and vehicle owners carrying out specific diagnostics or adjustments |
Requires a certain level of technical knowledge to fully exploit the data collected
|
Costs associated with electricity consumption
The cost of home and public charging stations
Electric vehicles can be recharged at home or at public charging stations, each with variable costs depending on a number of factors.
Home charging is often the most practical and least expensive option. Costs depend mainly on the residential electricity tariff, which varies according to supplier and tariff option (peak/off-peak). In France, the average cost of charging an electric car at home with a regulated tariff can vary from €0.1828/kWh in off-peak hours to €0.2460/kWh in peak hours. For a car consuming 15 kWh/100 km, this represents a cost of €2.74 to €3.69 per 100 km driven.
The costs of public charging stations vary more widely due to the different levels of service (slow, fast, ultra-fast charging) and the pricing policies of each operator. For example, a charge at a fast charging station may cost around €0.40 per kWh at Tesla, while other networks may charge by the minute, such as Ionity, which offers rates of around €0.59 per minute. These costs can significantly increase the total cost of recharging, especially for fast or ultra-fast sessions.
Also read → How much does it cost to recharge an electric car?
Cost comparison with combustion vehicles
Electric cars, although more expensive to buy, can offer significant savings on running costs. Let's take the example of a typical electric car consuming 15 kWh per 100 km. With an average electricity rate of €0.20/kWh, this equates to a cost of €3.00 per 100 km. By comparison, a petrol car consuming 6 liters per 100 km, with the price of fuel at €1.50/litre, would cost €9.00 for the same distance.
Electric vehicles generally have lower maintenance costs than gasoline-powered vehicles. This is due to fewer moving parts and the absence of complex systems such as internal combustion engines and traditional transmissions. Estimates suggest that maintenance costs for electric vehicles can be reduced by 30 to 40% compared with gasoline-powered vehicles.
The government offers numerous tax incentives for the purchase of electric vehicles, such as the bonus écologique and the prime à la conversion. These compensate for the higher initial cost. These incentives also include tax reductions, tax credits, or exemptions from certain charges.
Also read → Cost comparison with combustion engines
Conclusion
It is therefore important to fully understand the factors influencing electric car consumption, to ensure clearer and more effective adoption. From eco-driving that optimizes energy use to analyzing recharging costs, every aspect plays a key role in maximizing energy efficiency. In a world rapidly transitioning to more sustainable solutions, becoming familiar with these elements enables consumers to make informed choices that support both the environment and personal economics.
