this post was submitted on 06 Jan 2024
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Did the YouTuber run the same type of test that the EPA would run?
I feel like every car I’ve ever owned has had worse milage than what’s on the sticker. But maybe I have a lead foot.
You probably do have a lead foot. I can usually best the sticker mpg especially with hybrids.
Is hypermiling different in a hybrid or an EV compared to say an old manual transmission ICE?
EDIT: To be more clear, I guess I was more curious about techniques used. I already am aware how much waste heat and energy there is in ICE vehicles.
One difference is EVs have regenerative breaking. Using your brakes in an ICE is 100% wasted energy, while regen breaking in an EV returns some (I don't know what percentage) of the car's kinetic energy back into the battery.
Hybrids have regen as well. Some phevs and some evs let you set the regen strength so you can either brake by letting off the accelerator (highest return to the battery) or you can just coast (lowest return) or somewhere in between.
For more info, look for one pedal driving. If either my current or last car had adjustable regen I'd probably be able to do even better with efficient driving.
I've worked some hypermiling concepts into my driving but I don't really go full on with it. I still haul ass on the highway and will gun it when needed.
The easiest things people can do are overinflating your tires by 10-15% along with watching both upcoming stop lights and the brake lights of the cara in front of you and not just the one directly in front of you, when it looks like traffic is slowing down, let off the gas and coast. I coast as much as I can, especially towards red lights, stop signs and highway congestion.
It's far more effective in an EV. With an ICE about 80% of the energy is just generating heat so you've only really got the remaining 20% that you can influence.
I don't think that's true. The issue is the amount of storage available for the regen to go. With a regular hybrid you have enough battery for maybe a couple of miles on battery depending on several factors. With a plug in you have anywhere from 15 to 30+, I think the latest prius was supposed to have something like 100 miles of range. With the larger battery the regen can be more effective on the efficiency.
It's also dependent on the strength of the regen. There is what people are calling one pedal driving when the regen is set as high as possible, the motors will immediately start slowing the vehicle as soon as you let off the accelerator. The regen is also way more effective in the city. On the highway you'd probably want it set as low as possible. I don't yet have a vehicle with adjustable regen so I haven't personally tested out various scenarios to figure out what is more efficient.
The regen level probably makes no difference if combined with already efficient driving. The idea of coasting by letting off the pedal fully in an EV is flawed. You "coast" in an EV by holding the pedal in a neutral power setting.
He ran his standard test. Most other EVs in this test exceed the EPA range, most notably he recently tested the EV9 (a literal brick) in similar temperatures.
Good to know. Sounds like this is just the same old shit Elon / Tesla just got slapped for by the feds.
The EPA highway test is 55mph or something around that. These real world tests are all 70mph+
The only way you do better or equal on a 70mph test is
Advertise a smaller range than you actually have
Gear the motor for high speed and have worse performance at lower speeds (EVs typically do better at low vs high, but you could make low even worse)
Have a multi gear motor like Porsche and I think some Audi. Then you don't have to optimize the motor on 1 gear, but it substantially increases cost (but it's a porsche) and complexity and repair costs.
The EPA just needs to make a 70mph test part of the test cycle and make them advertise that.
The gearing in the Taycan/E-Tron GT aren't for efficiency, but for speed. Electric motors don't really lose efficiency as they spin faster, but they do start to lose the ability to move the car faster against the exponentially increasing wind resistance. This isn't an issue for most cars (they top out around 110mph), but for something like the Taycan it's important (tops out around 155mph).
The 70mph situation is more that manufacturers de-rate their cars. Both the Taycan and the Lyriq (a SUV brick) are well-known for demolishing their EPA ranges in 70mph cruising tests. Even the EV9 (the brickiest brick) exceeded the EPA range in this same test.
Unrelated to my other reply - but I think it'd be interesting to see how much other manufactuers de-rate their cars, by having independent testers also run an EPA test just like they run real world tests.
I'd love to see them run reports saying XYZ car has an actual epa range of XYZ even though they report ABC
This is right from energy.gov
https://www.energy.gov/eere/amo/articles/determining-electric-motor-load-and-efficiency
They also run more poorly below 50%.
To get a good city/highway range they would need to try and keep the motor above 50% for city, while also keeping it ~~under~~ around 75% for highway. How you move that gearing will impact range at higher speeds or lower speeds. Maybe it's not as much as I think, but it definitely comes into play, and the Taycans geared motor helps some amount.
Tesla has definitely honed their motors to maximize the EPA range vs higher speeds in addition they aren't de-rating like some other manufactures do.