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Comment by slg | Hacker News Reader

The first sentence of the article:

>After surprising many with the Air's 517 miles of EPA-estimated range...

A few paragraphs later in the article:

>During a real-world ride along with Lucid in one of the company's prototypes traveling at 70 miles per hour on the highway, the Air achieved 458 miles before depleting its battery. The automaker still needs to deliver a production vehicle to the EPA before it has an official EPA number. It expects to do so in early 2021 when the Air goes into production.

Isn't that opening incredibly misleading? The car does in fact not have 517 miles of EPA-estimated range. The company is projecting 517 miles of range once the EPA tests it, which has not happened yet. So why are they calling the 517 number "EPA-estimated"?

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Even 458 miles (737 kms) of highway EV driving at 70mph (112 km/h) is phenomenal. If this is coupled with a relatively fast charger infrastructure (150KW+) this means game over for fossil cars. When you can drive for 6 hours or more on a single charge there is absolutely no inconvenience factor in owning an EV at that point.

A lot of countries are still interested in fossil cars because they can slap their bullshit taxes on them and the gas, so I wouldn’t expect an instant transition, as it’s going to severely impact lobby-backed revenue streams

Most countries once EV's are cheaper than gasoline and diesel cars are going to outright ban gasoline and diesel cars so they don't have to import oil and pay for it in dollars.

EPA test is not a real world test. It’s a specific format.

The EPA is a government agency not a test. Calling it "EPA-estimated" implies the EPA is the one who did the estimating and not that it is a projection of what the car will get on the EPA's test.

The EPA doesn't even do the range testing themselves. Manufacturers do the test based on EPA specifications and report the results.

And FWIW, BEV's rarely get the "EPA-estimated" results except in ideal conditions. 55 mph, windows up, warm day (cold temperatures = denser air = more wind resistance), climate controls off.

My Model 3 Performance is rated for 299 miles. Based on a 150 mile trip in 35F weather at 75 mph with the heater running I took last year, my "real world" range is as low as 240 miles.

Cold conditions reduce range mainly due to use of cabin heat and battery temperature (which may even require wasting power on battery heating), not denser air. But the general point still stands.

Does the 70mph have an effect? In ICE, there is an MPH window where the engine is most efficient. Driving outside of that window will lower the miles per gallon and the total miles per tank. Is there a similar sweet spot for EVs?

The "most efficient" speed is pretty shockingly low, like 25mph to 45mph low depending on if you have "overhead" loads like AC/heat/lights/etc... (for a Tesla Model 3 at least)

And the 70mph does have a MASSIVE difference. Anecdotally, going from 65mph to 75mph in my Tesla absolutely destroys my range (last time I checked, the extra 10mph there would reduce my range by about 60 miles).

But that can be misleading in the real world. If you care about "time efficiency" as in "what speed should I drive to complete a long distance trip in the least amount of time", the most efficient speed for Teslas is something like 90mph! That's because the Tesla superchargers are so fast that they make up for the loss in efficiency from going much faster.

This is a good video on someone that actually did the testing to figure that out:

https://www.youtube.com/watch?v=cS2Vp9Y_jrc

Interesting bit of "for science" this guy did. I've never looked into buying a Tesla. Just out of my price range. When you buy a Tesla, does it come with a charger for the home, or do you have to buy it separately? 190kph is absolutely insane, even on open highway.

It comes with a home charger, and it's charge speed differs quite a lot depending on where you live and what kind of power source you can give it. In the US it comes by default with an attachment for our normal wall plugs, but at 120v and 12A the charge rate is pretty slow, about 6 miles per hour. With a higher power wall plug you can get it to about 30 miles per hour of charging with just a $15 adapter.

If you buy a separate standalone charger, you can get that to around 45mph of charge speed, but I tell everyone considering it to wait a bit before getting it because the vast majority of people won't need the extra charging speed.

EDIT: I was VERY wrong about the charge rate of the default plug.

3 miles per hour of charging. so for the stock 250miles per full charge would take 3.5 days to get a full charge? why do we not hear more about this in the discussion?

Whoops, I was WAY off, it's 6 miles per hour with a "standard" wall plug. You can see charging speeds for the different models and power at [1].

But even still most owners get a higher power plug installed as in the US our standard plugs are pretty low power and limited. We need higher power outlets for all kinds of things like water heaters, dryers, ovens, and EVs.

Also keep in mind that it's extremely rare to need a "full charge", you only need to charge what you used from the last time you drove, so unless you routinely drive 100+ miles a day, the standard outlet will probably be enough.

[1] https://www.tesla.com/support/home-charging-installation/wal...

A "standard" wall plug (i.e. 120V, 15A, which is actually 12A continuous) charges at 5-6 miles of range per hour for a Model 3.

You don't get 11mph of charge unless you use a 240V-15A outlet. The 11mph you quoted assumes a 240V outlet.

In practice, as you state, even with 5mph of range, taking multiple days to charge isn't actually an issue since you aren't fully filling up your car from empty every day.

Thanks, I'm all kinds of wrong today!

what's so insane there? Even my very old ICE powered conbustion car drives 180km/h nicely with 70kW. And now tell me, why Tesla the Model S needs a 700hp setup?

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