Indium Blog

Power Consumption for Electric Vehicles (EV)

  • Indium Corporation
  • e-Mobility

  • I've recently (Dec 2018) had a chance to do some thinking and reading about the growth of electric vehicles (EV) and their power requirements. It should be no surprise to anyone that electric vehicles are here to stay, and the slow demise of the internal combustion engine (ICE) in the next ten years seems certain. 

    First stop was to try and work out what may be the biggest question of all: how much electrical power would it take to convert 100% from ICEs to electric vehicles? I've focused on the USA for this example as that is where I have the clearest data. People have done this before, of course, but they usually start with the power consumption of the car; for me, it's about the efficiencies of power transfer from the charging station to the vehicle itself. Now we have clearer data on the electrical power used in super-fast charging and how far that car can drive on the given charge.

    Some caveats and clarifications (I know "back of an envelope" calculations can be out by an order of magnitude or more). I am assuming:

    • Timeframe: 2018 as baseline
    • Conversion to electric: complete conversion from ICE to EV in the current time frame
    • Fastest car charging: the ability to charge up a car in the same timeframe as it takes to pump a tank of gas (petrol) and the simple availability of charging stations en route are the biggest drawbacks for EVs on longer-haul journeys
    • Vehicles: the category of all "vehicles" can be approximated as "all cars" (I've lumped togther trucks and motorbikes under cars).
    • Efficiency: I00% efficiency of power transfer from the grid to the charging station.

    Let's start with the number of all motor vehicles on the road in the USA, which comes out at around 275million. For a baseline, there are currently less than 1million EVs on the road in 2018. The United States produces about 4 trillion (4 * 10^12) kW.hrs per year (yes: that's trillions of kilowatt hours) - still produced mostly from burning fossil fuels. Fast charging at 450kW for 3 minutes allows a car to move 62 miles. This was a key missing data point until very recently. 

    Now assume that the average USA-based car is driven 13,500 miles per year, giving a final required increase in USA electrical power generation of around 35% over the 2018 estimate. 

    Show my working? Glad to!

    (C)Copyright Indium Corporation 2018

    I would appreciate comments and corrections, as always.

    Cheers!   Andy