Here’s how the EPA calculates how far an EV can go on a full charge

boem@lemmy.world to Technology@lemmy.world – 96 points –
Here’s how the EPA calculates how far an EV can go on a full charge
arstechnica.com
9

So they do a series of very precise, complicated drive cycles (with a few different options of which cycles and fuzzy math multipliers) to estimate a number that people will never reach because they're doing 80mph. But somehow to anti-ev people it's only electric range that is an unforgivable lie, not ambitious MPG ratings. It seems like a disadvantage to use a different rating system but I guess you can't trust the gen pop to understand MPkW since they can't picture a bottle of 1kW

So this value should only be used as a horizontal comparison metric (i.e. one car to another) and a rough estimate of overall range, just like listed MPG has always been.

Honestly it's not even a rough estimate. ICE cars only convert something like 20% of the energy to actual power at the wheel. That means, in practice, range is mostly just about how much time you're behind the wheel. It would make more sense to estimate ICE range in hours than miles.

EVs are more efficient, so in practice, particularly on long trips at high speed, range will vary dramatically depending on what's going on aerodynamically, which changes dramatically from one second to the next.

  • kWh please

And it's like a bottle of battery volume if you like to think of it that way.

I suspect most people wouldn't really know how big a gallon is either. They care about how much they pay per gallon, and they just don't know that their electricity bill tells them how much they pay per kWh.

Americans often buy milk by the gallon and have various 1-5 gallon gas cans for common gas powered equipment (lawn mower, leaf blower, generator). I beleive a gallon is tangible here. I'm sure ~4 liters is tangible for metric countries although they often use l/100 miles so they just need to know 1 liter, which I assume many drinks are sold as such

This is the best summary I could come up with:


The simple explanation is that an EV is driven until the battery runs flat, providing the number that goes on the window sticker.

In practice, it's a lot more complicated than that, with varying test cycles, real-world simulations, and more variables than a book of Mad Libs, all in an effort to give you a number that you can count on to be consistent and comparable with other vehicles on the road.

The EPA's Urban Dynamometer Driving Schedule is the official "city cycle" test loop.

The total test time is 1,369 seconds, the distance simulated is 7.45 miles (12 km), and the average speed is 19.59 mph (32.11 km/h).

The highest speed reached on the test is 56.7 mph (91.25 km/h), and there are several periods where the vehicle sits stationary.

For higher speeds, vehicles complete the Highway Fuel Economy Driving Schedule (HFEDS).


The original article contains 681 words, the summary contains 143 words. Saved 79%. I'm a bot and I'm open source!

This isn't really an article that can be summarized. I beleive it's 3x or 4x longer than the bot read. It's split into several sections for different cycle types and calculations.