Prius mpg?

[SHRED]

What "real world" mileage does the new Toyota Prius get?

My friend told me the they are over-hyped as far as MPG goes.
Later I asked an owner I saw getting out of one in a parking lot and she said they get around 40 mpg and not the 55 to 60 as claimed.

WTF?

Any owners out there that can help clue me in?
I am considering getting one.

[Downtown Hound]

1. I averaged between 48-52 in my 2005 Prius

A couple of times it did go up to 56 and sometimes it would dip around 44. Not quite what they advertised, but then again, no car is. I was very happy with my mileage, and the Prius was a pleasure to drive.

[MelissaB]

16. That's about our average, too. We've never had a tank under 48 mpg though.

We do get better mpg in the spring and when the tires are pumped up. I also get better mpg than hubby because I enjoy working at it and he drives it like a regular car (not that there's anything wrong with that). It's like playing a computer game to me. :)

[Drifter]

2. It has everything to do with ...

how you drive.

I have a Civic Hybrid. I can get 52MPG when I work hard at it.
My wife and daughter don't get much over 40MPG.

Most people do not know how to drive with saving gas in mind (this has nothing to do with Hybrids, it has to do with your acceleration and deceleration behaviors).
The posted MPG will most likely be higher than your average driver will get.

The easiest way to explain how to drive to maximize gas mileage

"Pretend you do not have brakes."


Cheers
Drifter

[madokie]

13. so true

[Greyskye]

20. the other big factor

I have a Prius and agree completely with you. The other big factor is the terrain that you're driving in. If you are in completely flat country, by using good hybrid driving techniques you can get great mileage.

If, however, you live in hill country as I do, it gets a lot trickier. It's hard to get over 45mpg living in the Sierra foothills. Sure you're not using any gas on the downhill stretches, but going uphill can easily take you below 15mpg. That really makes it difficult to keep up the average.

[whistle]

3. When it comes to stated mpg, auto manufacturers lie so that

....22mpg city/28mpg highway in reality for virtually all owners is realy 18mpg city/24mpg highway. That's a 17% to 22% overstatement. In the case of the Toyota Prius the overstatement in this example is 37% to 50% although I have a friend who says he gets 45mpg to 50mpg although he might be saying that to save face as he is a lawyer.

Now, why auto manufactureers can make such outragious claims is where poltical corruption comes in. They do it because they know they can get away with it.

[krispos42]

32. It's because the EPA system is wildly optimistic

and wildly unrealistic. I think one of the parameters is highway cruising at 55 MPH, which is virtually unheard of.

Supposedly this model year they are rolling out a new testing regime that will give numbers more in line with real-world driving.

[Gregorian]

4. Miles per gallon for a hybrid is only part of the true mileage.

I have seen 57 mpg posted in, I think this forum.

You also pay for energy that is used to power the electric motor. But that is usually ignored since it is cheaper than gas. But the truth is, it's part of the equation.

[Downtown Hound]

17. How is it part of the equation?

The Prius uses regenerative braking, meaning that every time you step on your brakes, you charge the battery. If you drive for long periods at a time without using the brakes, then the gas charges the battery. So you end up getting a little bit less MPG, but that's why the Prius gets better MPG in the city than it does on the highway. You never have to plug the Prius in and therefore you don't end up paying anything extra except for the little bit more you pay in gas if you go on long road trips.

[Gregorian]

18. I didn't finish my thought.

I realized this morning that I didn't say what I had to say.

Yes, regenerative braking charges the battery. But it's not a free ride. Regenerative braking takes braking energy and puts it into the batteries, rather than heat. Braking energy only. Not energy that was used to power the car down the street. That is much greater. In other words, you only get a tiny bit of energy from braking as compared to driving the car around. That's the reason electric is so elegant.


But the issue about miles per gallon is this- For simplicity's sake, let's assume the electricity on the grid is powered by petroleum. It could be hydroelectric or nuclear. But for the most part it's petroleum. That has it's own "miles per gallon". In other words, when you charge the battery with the wall outlet, you are using fuel. There is your "other" mpg.

So don't let the gas tank needle fool you. It also takes petroleum energy to push the car around with the electric motor. How many miles per gallon, we can't easily say without doing a study. I'm sure that study exists. It's not too difficult to calculate.

What people don't want to seem to realize is that it's not the car that is doing anything for the environment, except the obvious higher miles per gallon. It's how we generate electricity that is the true issue here. But you might need a degree in engineering in order to see it clearly. I think people have a lot longer road ahead of them before they really understand what's going on.

[IDemo]

28. from another post of mine today (GD) on this topic

Saying that electric vehicles or plug-in hybrids return "X - mpg" requires a qualification: they are still using energy, even if not carbon-based. But they ultimately will use far less of it no matter from which source.

Comparing the total energy usage of vehicles which use completely different fuels and propulsion systems is referred to as a "well-to-wheel" analysis. By using a common measure of energy such as megajoules, it is possible to derive "equivalent miles per gallon" (or kilometers per megajoule) for non-internal combustion vehicles. Beginning with the energy content of the source fuel from the ground, and removing the energy required to refine/process it and transport it to filling station or electrical outlet yields a "well-to-tank" (or "well-to-station") efficiency number. The "tank to wheel" figure follows: internal combustion engine and drivetrain efficiency, versus the efficiency of motor/motor controller and battery charging for an electric vehicle. It is here where electric vehicles blow internal combustion out of the water.

Well-to-wheel analyses have shown that EV's such as the Tesla do indeed return very much higher numbers (as much as double) than even very fuel efficient vehicles like the 1993 Honda Civic VX (EPA-rated at 51 mpg).

[Gregorian]

29. Second Law thermodynamic efficiency of the larger power generation is why.

It's in agreement with what I said.

The only difference between charging batteries and just running off the engine (as long as batteries are being charged on the grid, and as long as we assume the grid is primarily petroleum powered) is the efficiency of the power generation device. That would most likely be a petroleum fired steam turbine. Due to it's size, the second law efficiency is much greater than that of a standard auto engine. But there are also capacitive losses to ground in the power transmission.

The problem is that we are still not generating that power in a renewable fashion. Once power is generated without a carbon emission, then none of this even matters. and I wouldn't use "blows out of the water" as a description. It's not THAT great. Probably closer to double the mileage on the electric motor driving of the car. I guess that would qualify as blowing out of the water. But here's the issue that I think everyone is missing. Even if electricity is generated without any carbon footprint, the fact that there are literally billions of people in cars is the reality. We need to pay attention to this. There is nothing to be proud of in creating new cars, electric or not. Sure they're better. But how much better? That is the question. Better enough to make it so billions of people are suddenly living within the equilibrium of nature. I don't think so.

[IDemo]

30. I guess my post really didn't apply for non-pluggable hybrids

Petroleum-fired generators make up only a fraction of the current grid mix, about 8%. Coal makes up about 55% in the US, natural gas and nuclear most of the rest. But studies have shown that 1) the existing grid has enough spare capacity to power about 84 percent of our present vehicles, 2) the total energy requirements to do so would be much less than an equivalent number of gasoline and diesel powered vehicles, and 3) the carbon and other greenhouse gas reduction would be significant, even in areas where coal is the primary generation fuel. In places where hydro or nuclear prevail, the benefits would be tremendous.

I'm certainly not saying that EV's will have us merrily continuing on for another century. But when the supply side of the transportation energy equation -- oil and biofuels, appears to have major issues, energy efficiency and conservation remain the only side of the equation. Electrifying our transportation will provide at least some buffering against the approaching energy and climate storm.

[Gregorian]

31. The only thing that will help is getting away from petroleum.

War and combustive carbon dioxide emissions are killing us and the planet.

Anything else is just polishing a turd. We can be more efficient, but that isn't going to solve much. Especially since two billion people are just joining in on the modern lifestyle.

[Poiuyt]

5. Here are some tips on maximizing mileage in hybrids:

http://www.hybridcars.com/gas-saving-tips/maximizing-mileage-honda-civic-hybrid.html

http://www.kbtoyota.com/priusmileagetips.html

http://hybridcaradvisor.com/maximizing-your-mileage-with-hybrid-cars.htm

[Maat]

6. I get 48-49 MPG every tank .... at least ...

and I do in-town driving.

I love it. My hubby is an engineer, and he says that nothing out there matches the Prius technology - he loves it (he's slightly biased, I'm sure); HOWEVER, I'm pleased as can be with it. I have the GPS and bluetooth features. I love that car WAY TOO MUCH! Hubby says my car really runs on 'an aura of superiority (mine)(we saw that phrase on the 'net - another Prius-lover). Mine is a 2006.

[LordJFT]

8. if you drive under 11mph you get infinite mpg

[Strelnikov_]

10. At 11 mph most of the chemical energy consumed is converted to heat

so you get very low mpg.

ICE passenger vehicles have a plateau of peak efficiency (mpg) between 45-55 mph.

[Greyskye]

19. at that speed in a Prius...

...you aren't running the IC engine. The car is in electric 'stealth' mode until you either punch the gas, or the main batteries run out of juice.

That's what the person you were responding to was referring to.

[Strelnikov_]

21. Yea, Right

Considering the ICE must kick on to recharge the battery, that isn't really infinite mpg, is it.

And I seriously doubt that pulse/glide at 11 mph is more efficient in mpg than simply running at, say 40 mph.

Every time the ICE kicks on to recharge the battery, it is a fairly inefficient process (heat, mechanical losses) to recharge the battery.

The design concept behind the Prius HSD drive is to:

1) Recoup energy (momentum and gravitational) using regen braking.

2) Allow for limited EV movement allowing the ICE to shut down at low speeds/stops.

3) Provide intermittent power as needed to allow use of a smaller ICE operating near peak efficiency.

[Greyskye]

22. um, yeah, right.

:shrug: What part are you disputing? :shrug:


I admit that you don't get "infinite" mpg, but you certainly can't apply ICE rules to a hybrid engine.



EDIT: The post I responded to was this:

yeah, right n/t

It has obviously been extensively (read, completely) edited.

[Strelnikov_]

23. OP states infinite mpg, you admit no infinite mpg

So what part are you disputing?

And since a Prius IS an ICE powered vehicle, ICE rules still apply.

[Greyskye]

24. Question

Do you understand how the hybrid drive works? Under a certain speed, the ICE does not even turn on. As long as the battery charge is above a certain level, the speed isn't over the ICE trip point, and you don't punch the accelerator; you are operating as an electric vehicle only. When in that mode, ICE rules do not apply.

EDIT:

Sheesh, I now see that you've since edited the post I replied to, and added a whole lot more info that you previously did not have in your original post. Poor form, that. :eyes:

I was only speaking to electric only mode at extremely low speeds. Obviously, in a real world situation that's not remotely practical.

[Strelnikov_]

25. "Poor form, that."

Tough.

[Greyskye]

26. *plonk*

Thanks, that reply tells me everything I need to know.

[Strelnikov_]

27. Back at ya

[kestrel91316]

34. Heck, if I drove one to and from work I could keep in under 35 MPH and

probably get 100 MPG, lol. Sounds tempting, except work is only 3 miles from home and it STILL wouldn't save enough money for me to justify a Prius over a Corolla. But if I win the lottery it's the first thing I buy.

[peacebird]

7. we average 55 -58 in summer and 48 in winter but we also drive from the mtns

to Cville and back each day. It's a 20 mile each way commute on the highway so we are not the "ideal" prius owner - the ideal would be mostly city driving....

[petersjo02]

9. I spoke to a friend of mine day before yesterday

He told me that his Prius gets 50 mpg. It is about 5 years old and has over 100,000 miles on it, still going strong.

[The_Casual_Observer]

11. It's kind of like asking how big the fish was.

It's going to be a big number.

[skids]

12. Mid to high 40's in winter, 50+ in summer.

That's with 2/3rds highway 1/3rd country, with no AC running.

It gets 60-70 in pure country driving during the summer.

[happyslug]

14. Prius mileage

Mileage is directly related to speed and being a pest. If 20
mph can be maintained then 99 mpg can be achieved. Interstate
mileage can be 60 mpg if you like to be rear ended ie your
speed will be between 30 to 70 mph (mostly 30 mph). 

[Javaman]

15. Read this...

Mother Jones: This Guy Can Get 59 MPG in a Plain Old Accord

http://www.thesimpledollar.com/2007/01/13/mother-jones-this-guy-can-get-59-mpg-in-a-plain-old-accord/

[kestrel91316]

33. Everybody I have talked to says about 50.