All EVgo charging plans bill based the duration of a charging session not the kWh dispensed and the rate is the same regardless of the speed of the charger (50, 100, 150 or 200kW). The amount of kWh dispensed during a charging session will depend on a number of factors including:
- How full your battery is at the start of the charge session (this is called state of charge). The more your battery is charged the slower the charge rate will be. EVgo does not recommend you start a fast charge session if your vehicles at or near 80% state of charge as the cost to bring the battery to full may be high for the amount of energy delivered. A level 2 charge session would be the cheaper option unless you are in a hurry.
- How long you’ve been driving your EV before starting a charge. Batteries don’t like to be too cold or too hot and if the charge rate slows down in both cases. It is however very difficult to know how your EV manages battery temperatures and something you’ll need to learn from experience.
- How long you fast charge. A fast charge session that starts at a low state of charge, say 20%, and a warm battery will charge at as fast a rate as the EV and charger can deliver, but as the battery fills up and heats up and the charge rate slows.
- The voltage and current ranges your EV battery operates in. For instance EVgo’s 50kW chargers provide 125A up to 400V (125x400=50,000) and then decrease the current down to 100A at 500V. EV batteries tend to operate in the mid 300 to low 400V range, however, some operate in the low 300V to mid 300B range. As your EV battery chargers the voltage increases. For EVs with batteries in the lower voltage ranges a 50kW charger will deliver less than 50kW due to the current limit of 125A and voltage less than 400V.
- Batteries can deteriorate over time and lose capacity as they do. This also affects their charge rate which decreases as well.