Is there enough capacity to charge electric buses?

THE EDITOR, Madam:

I recently read in The Gleaner that the Government intends to procure 200 additional electric buses over the next three years. I am concerned that our infrastructure and generating capacity will not be able to cope with this venture.

Below are some statistics for the general public and the authorities to consider.

The amount of power required by a charging station to charge an electric bus depends on several factors, including the battery capacity of the bus, the desired charging time, and the efficiency of the charging system.

Key factors:

Battery capacity (kWh): Electric buses typically have large battery packs, ranging from 150 kWh to 600 kWh or more, depending on the size and range of the bus.

Charging time: The desired charging time determines the power requirement. Faster charging requires higher power.

Charging efficiency: Charging systems are not 100 per cent efficient, so some energy is lost as heat. Efficiency is typically around 90-95 per cent.

Charging rate (C-rate): This is the rate at which the battery is charged relative to its capacity. For example, a 1C rate means the battery is charged in one hour.

Power calculation: The power required (in kW) can be estimated using the formula – Power (kW)=battery capacity(kWh) charging time (hours) power (kW)= charging time (hours) battery capacity (kWh)

Typical power levels for electric bus charging:

Slow charging (overnight): 50 kW to 150 kW

Fast charging (opportunity charging): 150 kW to 350 kW

Ultra-fast charging (depot charging): 350 kW to 1 MW or more

Infrastructure considerations:

High-power charging stations (e.g., 350 kW or more) require significant electrical infrastructure, including transformers, high-capacity cables, and cooling systems.

Grid capacity and local utility support are critical for high-power charging installations.

The power required for charging an electric bus can range from 50 kW to over 1 MW, depending on the battery size and desired charging speed.

For the Jamaica Public Service Company, The total installed capacity of Jamaica’s power grid is approximately 1,200 megawatts (MW), with daily generation varying based on demand, which typically ranges between 600 MW to 900 MW during peak periods.

CUTEL FRANCIS