How To Calculate Charging Power of a EV Charger?
Jun 18, 2024
To calculate the charging power (kW) over an hour of an electric vehicle (EV) or plugin-hybrid vehicle (PHEV) charger, you can use the formula described in the sections below that considers the amperage, voltage and the number of electrical phases. For your convenience, We have calculated and created a table that shows rated charging power at varying amperage, voltage, electric phases. The below also answers your questions of how many amps is a 22kW EV charger and how many amps is a 7kW EV charger. The efficiency loss is not included in this calculation due depending on several factors.
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Australia Rated Charging Power (kW) |
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depow Portable Charger->
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15A & 10A Plug
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7kW CEE 5 Pin
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22 kW CEE 5 Pin
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Amperage
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230V / 1-phase
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230V / 1-phase
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400V / 3-phase
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6
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1.4 kW
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1.4 kW
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4.2 kW
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8
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1.8 kW
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1.8 kW
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5.5 kW
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10
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2.3 kW
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2.3 kW
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6.9 kW
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13
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3.0 kW
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3.0 kW
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9.0 kW
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16
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-
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3.7 kW
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11.1 kW
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20
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-
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4.6 kW
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13.9 kW
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25
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-
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5.8 kW
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17.3 kW
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32
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-
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7.4 kW
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22.2 kW
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All EU Countries Rated Charging Power (kW) |
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depow Portable Charger-> |
Schuko v1 & v2 |
11 kW CEE 5 Pin |
22 kW CEE 5 Pin |
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Amperage |
230V / 1-phase |
400V /3-phase |
400V / 3-phase |
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6 |
1,4 kW |
4,2 kW |
4,2 kW |
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8 |
1,8 kW |
5,5 kW |
5,5 kW |
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10 |
2,3 kW |
6,9 kW |
6,9 kW |
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15 |
3,5 kW |
10,4 kW |
10,4 kW |
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16 |
- |
11,1 kW |
11,1 kW |
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20 |
- |
- |
13,9 kW |
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25 |
- |
- |
17,3 kW |
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32 |
- |
- |
22,2 kW |
Typical home electric outlet uses 230V and 1 phase
Formula for Charging Rate
Charging Power (kW) = Voltage (V) X Current (A) X Number of Phases / 1000
Explanation of Terms
- Voltage (V): The electrical potential provided by the charger, typically in volts.
- Current (A): The current supplied by the charger, typically in amperes.
- Number of Phases: The number of electrical phases in the charging system. This is typically 1 for single-phase or 3 for three-phase systems. This is approximately 1.732 or sqrt(3), and is used in three-phase power calculations to account for the phase difference in a balanced system. For a single-phase system, this factor is not used.
Single-Phase System
For a single-phase system, the formula simplifies to:
Charging Rate (kW)=Voltage (V) × Current (A) x Num of Phase (1) / 1000
Three-Phase System
For a three-phase system, the formula is:
Charging Rate (kW)=Voltage (V) × Current (A) x Num of Phase (1.732) / 1000
Example Calculations
- Single-Phase Example:
- Voltage: 230 V
- Current: 10 A
Charging Rate = 230×10/1000 ≈ 2.3 kW
- Three-Phase Example:
- Voltage: 400 V
- Current: 32 A
- Number of Phases: 3
Charging Rate = 400×32×1.732/1000 ≈ 22.2 kW
Key Points to Remember
- The number of phases significantly impacts the charging rate.
- For single-phase systems, the calculation is straightforward without the 1.732 or sqrt(3) factor.
- For three-phase systems, the 1.732 or sqrt(3) factor is crucial to account for the power distribution among phases.
Using these formulas, you can calculate the charging rate for any EV charger by plugging in the appropriate values for voltage, current, and the number of phases. If you want learn how to determine your charging time for your electric car, read our article of How Long Does It Take to Charge an EV or PHEV.
