Electric Vehicle Association (EVA)

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Are you clear on range and charging time?

The EV basics you need to know

BY RON FREUND: Director, ELECTRIC AUTO ASSOCIATION

If you’re a new or about-to-be eclectic vehicle (EV) owner, you’ll find yourself adjusting to a whole new game plan when it comes to road strategy. You’ll be focused on how far you can travel on a single charge, as well as the length of time it will take to recharge the battery. It’s good to know everything you can when it comes to both.

Range

In most cases range is not a calculation, it is measured. The standardized vehicle test procedures from the Environmental Protection Agency (EPA) and the New European Driving Cycle (NEDC), as well as the Worldwide Harmonised Light Vehicle Test Procedure (WLTP), measure the average energy consumption under average circumstances (no air conditioning running, moderate outside temperatures, minimal wind conditions, and minimal elevation changes). The manufacturers use those averages to model and gauge their product behaviors. Then the range is derived from the capacity of the battery from fully charged at 100% to an indicated 0% state of charge.

Of course, everyone drives differently depending on many factors, hence "Your Mileage May Vary," but for the average driver, reaching the EPA stated range requires a constant highway speed of roughly 55 mph (90 km/h). Reaching the WLTP stated range means driving at approximately 50 mph (80 km/h), and for the WLTP range, approximately 30 mph (50 km/h). This means that the WLTP over-reports by approximately 10%, the NEDC over- reports by approximately 30%, and the EPA range might be a rough average if you do not often drive at freeway speeds.

Time

When it comes to the charging time, manufacturers generally report that Direct Current rapid charging time from 0% (or 10%) to 80% capacity is somewhere between 20 and 60 minutes. This assumes that the battery is at a moderately warm temperature (25°C-30°C) and that the charger can provide the maximum rapid charging speed.

A second oft-reported statistic is time spent at a public Alternating Current charger. Again assuming the infrastructure can provide the maximum power, the projected span is between 6 and 12 hours.


Final warning


With Internal Combustion Engine vehicles, waiting to refill the gas tank until you’re driving on fumes is unwise because fuel injectors can plug up on residue at the bottom of your tank, and this can translate into expensive repairs. Likewise with EVs, draining your battery pack until you can no longer move will damage the pack, and the computers will almost certainly log such behavior. Don’t go there!

Doing a little bit of mental math to decide if you have enough charge to arrive at your desired destination is not difficult. No need for super precision, just estimate, and give yourself a little extra at about 10%. And some cars will do that work for you!

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