How to Calculate Electric Vehicle Energy Efficiency
Understanding and calculating electric vehicle (EV) energy efficiency is crucial for comparing different EVs and estimating their operating costs. This calculator helps convert between various units used to measure EV efficiency.
Formulas for EV Efficiency Conversion
The basic unit of EV efficiency is kilometers per kilowatt-hour (km/kWh). Other units are converted to and from this base unit using the following formulas:
km/kWh to mi/kWh: \[ \text{mi/kWh} = \frac{\text{km/kWh}}{1.60934} \]
km/kWh to MPGe: \[ \text{MPGe} = \frac{\text{km/kWh} \times 33.7}{1.60934} \]
km/kWh to kWh/100km: \[ \text{kWh/100km} = \frac{100}{\text{km/kWh}} \]
km/kWh to kWh/100mi: \[ \text{kWh/100mi} = \frac{100 \times 1.60934}{\text{km/kWh}} \]
Where:
1.60934 is the number of kilometers in a mile
33.7 is the number of kilowatt-hours in a gallon of gasoline equivalent
Calculation Steps
Convert the input value to km/kWh if it's not already in that unit.
Apply the appropriate formula to convert km/kWh to the desired output unit.
Round the result to a reasonable number of decimal places (usually 2-4).
Therefore, 4 mi/kWh is equivalent to approximately 15.53 kWh/100km.
Diagram of EV Efficiency Conversion
The following diagram illustrates the concept of EV efficiency conversion:
This diagram shows the relationship between mi/kWh and kWh/100km. The height of each bar represents the relative efficiency, with taller bars indicating better efficiency (more distance per unit of energy or less energy per unit of distance).