Red Alert - Battery Mileage Varies on Prime Models

the pip was better than the prius because it was lithium vs nimh. i'm not sure prime is any better than gen4 lithium, and gen 2 prime with an even heavier battery will be interesting

 

i've never had any trouble exceeding the epa rating in my 3 prius and 2 hycams

 

All the cars tested for EPA are done so with high octane fuel. Of course, the raw results of that test are far higher than what appears on the window sticker. That's because people don't drive in that manner on the public roads, not because of the octane of the test fuel.

There is no 91 octane footnote for the mpg on Toyota's website. It appeared in one of the release video. It may have been included because power ratings were being discussed. The Lexus models with that foot note on the Lexus site do so for the power ratings. Or what I suspect, someone saw 91 RON listed under octane, and was ignorant that 91 RON equals 87 AKI, which is US regular.

 

What leads you to believe that high octane produces better MPG?

Octane ratings are not directly related to energy content. The ratings are instead connected to the ability of high power, high performance engines to rapidly guzzle that fuel without damaging themselves.

When different octanes do have different energy densities, it is almost always the lower octane that has the (only slightly) higher energy density. But it must sipped at much slower rates to prevent engine damage, which generally means the higher performance engines shouldn't be using it. Some engine designs intended for high octane may get lower MPG on lower octanes due to their self-protective measures. But most engines designed for 87 octane should get at least as good MPG on 87 as on 91, and sometimes may find that 87 even (slightly) beats 91, depending on details of the particular fuel batch's blending that generally never posted to consumers.

(Edited: was missing 'never')

 

...and further, some automakers trust those self-protective measures so much that they have published statements in their owners' manuals to the effect of "Use any fuel you like, just expect lower performance and MPG when using lower octane fuel"

So to the layperson, it can look like higher octane = more energy.

 

I estimated 38 mi vs. 42 miles. Apparently, the difference is larger. The reason for the difference is higher ground clearance and higher vehicle height due to larger-overall-diameter tires, which increases the coefficient of drag.

Superior specs of the base LE/SE trims | PriusChat

Leather seats are a downgrade in my opinion (hot in summer, cold in winter, always sweaty, wears out quicker, harder to clean and maintain, etc.), and most bells and whistles on the higher trims are not needed. SE is a win–win for most people.

 

The cloth seats on my 2004 were perfect after 13 years and 150,000 miles. The Softex seats on my 2017 Prime were permanently stained blue from Jeans after 3 months and so much less comfortable that I covered them with cloth seat covers.

 

I wouldn’t buy a plug in hybrid without carefully weighing the pros and cons. Starting with replacement battery cost. The regular Prius hybrid batteries are readily available, around $1600~3000 USD. Prime battery is astronomical priced, heavy as heck and very short supply.

This thread is of interest:

2017 Prius Prime with $15,000 rodent damage!?! | PriusChat

 

I’ve had the opposite experience with leather and cloth. My 2009 has leather and still looks brand new except for the shiny, slightly cracked parts of my driver seat. I’m really sensitive to cold and never feel cold on these leather seats. Softex is a different story and I would love to hear any long term experience. I’m guessing it’s probably going to be sticky in the summer but hopefully not colder than leather.

I previously had a Pontiac Vibe with Toyota cloth seats. Even a small water spill left a stain and a friend had similar experience with a Toyota.

I test drove 2022 Prius and Prime both softex and cloth. The softex seats were noticeably more comfortable and felt more supportive. Maybe just the quality of the seat. The cloth on the fabric seats was really rough. Hopefully improved in 2023.

Maybe I could put softer cloth covers on top of the LE rough cloth seats but I think I’d be missing one of the safety features included in the XLE/SXE. Need to refresh my memory. Plus that darn lower ground clearance.

 

And probably irrelevant since the battery is designed to last at least 15 years and 150,000 miles.

 

Specifically, octane is measure of gasoline's resistance to ignition from heat. In an engine, that heat is from compression. Engines that can use higher octane have higher cylinder pressures, which is mostly from having higher compression ratios. That means a longer power stroke to more efficiently convert the fuel's heat energy to kinetic.

Most high octane cars use that conversion efficiency for more power, but it can be used to improve fuel economy. Direct injection engines use regular octane, but have high octane level compression ratios. Cars using them have better power and economy than using a port injected engine.

In the case of the Prius, if the 2L truly uses higher octane, and that is for efficiency, the difference between 91 and 87 octane won't be worth it to most people. The difference in fuel economy will be in line between using E10 and ethanol free or summer and winter blends. For most of the country, a mpg boost from 91 won't be worth the higher price.

The difference listed in Canada is 53km to 64km.

The reason for the difference is the wheels, but mostly the weight. Replacing factory tires with a heavier model will hurt economy. The ~ half inch raise in height could have an aero effect, but not change the reported Cd difference between trims. If that exists, it is because of different external trim pieces or the wheel spokes.

 

battery is designed for 10 years, not 15. at 10 1/2 years, i would be trading in but for the poor new car price/availability

 

Why didn't you wear leather pants?

 

We need to get you a PHEV.

 

Nope. It's warranted for 10 (in CARB states). It's designed for 15 (median lifetime). Your confusion is justified since I mixed metrics in my post with a 15 design life and a 150,000 mile warranty. The mileage expectation is closer to 250,000, with half the miles on electric and 70% capacity remaining.

 

Pros:

172MPGe vs 56MPG.
Can fill up at home - no visits to the gas station.
I fill up on my solar power (sized for this application) costing me $1.70/equivalent gallon for the next 30 years or so.
Much more pleasant to drive in electric mode than in hybrid mode.
No worrying about the wear and tear and inefficiency of short trips.
Much more responsive.
Virtually silent at any accelerator pedal setting.
You aren't polluting.
You have enough battery power to run significant portions of your house in an outage (like refrigerators and lights) without having to figure out how to get your exhaust out of the garage.
Did I mention no visits to the gas station? I basically never fill up unless I'm on a road trip. The last time I filled up was last May 300 miles from my house.
Oil changes once a year, at most.
Backup source of propulsion if something goes wrong with the gas system.
Not subject to the whims of the global oil market (much more stable pricing even if you don't have solar).
It's fun to try to plan trips around charging needs. You get to learn apps and locations.
Even more range than the hybrid version.

Cons:
Slightly less cargo volume.
Slightly more expensive.

As I've said before, they shouldn't even sell a Prius hybrid anymore. The G4 should have been designed from day one as a PHEV only. Toyota is now two generations behind where they should be (G4 - PHEV only, G5 PHEV with BEV option is where they should be).

 

Thanks for the for-warning! I usually at least put a towel down because of my gardening/clay adventures but I better get covers. I was concerned covers could cause some weird wearing. Where does one find good covers? Have to wait until companies catch up with new seat design but is there a best brand that would be washable? Thanks!

 

2018 / 2017 interior differences? | PriusChat

 

Thanks!