Hybrids the Real Payback

joe131 · June 2007

I'll bet almost no one who has bought a hybrid will even keep it more than 5 years, so will likely not break even, much less come out ahead. The person who buys one is most likely to want the next "new and improved" thing to come along. When it does, he'll dump his old hybrid for the new car.
Boy, that Civic EX sure is overpriced! I wonder if they sell any near MSRP.

gagrice · June 2007

$1,551 - $1,071 = $480 annual gas savings with hybrid.

You left out one important detail. The $3100 -$3200 you save goes into a CD paying about $176 per year. So that $480 is now only $304 divided by 12 equals $25 per month. Even less when you consider the interest on that additional $3100+ per year will be from $175-$250. That takes your $304 savings to less than $11 per month.

Most hybrid owners found it easier to justify their purchase to feel green or have the latest in technology. No way is it anymore than that. Or in your case give it to the Japanese rather than the Alaskans, Canadians or Mexicans.

1stpik · June 2007

If you think people don't keep their hybrids, check the market. Toyota sells more than 100,000 Prius every year. Honda sells 60,000 Civic Hybrids. Visit carmax.com, ebaymotors.com and autotrader.com and see how many used ones are available. Nationwide, Carmax doesn't have ANY 2006 or 2007 Civic Hybrid. Only a few on ebay. See for yourself!

For older models, check for the Honda Insight and the first generation Toyota Prius (1999-2003). You won't find many. Owners keep 'em.

And you may think that the Civic EX is overpriced, but Honda sells every one that they make, just like the Civic Hybrid.

I doubt many people pay full msrp for them. But then, I paid $21,400 for my 2007 Civic Hybrid -- that's $1,200 BELOW msrp! Also got 2.9% financing from Honda.

In fact, if you visit the "prices paid" threads in this forum or on greenhybrid.com, you'll find most people paying far less than msrp for ALL hybrids.

I only posted msrp on both cars for reference purposes ..... you know, to keep the apples-to-apples comparison real.

Oh, and speaking of real, here's the latest real-world reading from my Civic Hybrid:

http://www.elementownersclub.com/forums/showthread.php?t=35198

HYBRIDS ROCK !!!

joe131 · June 2007

Very few hybrids are sold in comparison to all gasoline engine only cars sold. Not seeing a lot of ads for hybrids is expected, not an indication that owners don't dump them after a few years.
I just checked AutoTrader. There are 4,600 used hybrids for sale near my city. 1,200 are Civic Hybrids.

1stpik · June 2007

Neither you nor anyone else went out and bought a new car, then said, "Hey, I think I'm going to put $3,100 into a CD right away so I can justify buying an I.C.E. car over a hybrid."

Why not buy a standard car for $20,000, then put $200,000 into a CD because you didn't buy a Ferrari F 430? Think of all the extra money you'll make!

This is one more example of grasping at straws. But if you want to nitpick, why not include my $2,100 income tax credit in the equation. After all, those don't come with i.c.e. cars.

Round and round we go ..... where we stop, I know:

HYBRIDS ROCK !!!

joe131 · June 2007

There's a whole lot of disappointed hybrid buyers out there who discovered they could not even get the often touted tax credit when they got around to filing their tax returns. Check the forum titled, "Tax credits, What tax credits?" dealing with the diffiulties and impossibilities of recovering those hybrid tax credits.
And here's another one: http://townhall-talk.edmunds.com/WebX/.ef32446/246

joe131 · June 2007

Investing $3100 is not grasping at straws. And there are ways to earn a whole lot more than CD interest on it too.

1stpik · June 2007

4,600 used hybrids in one city?

Really?

How did you find only hybrid vehicles on autotrader.com? They don't offer a search for hybrids. Autotrader also doesn't differentiate between the Civic and the Civic Hybrid in its search features.

Also, what city? And what mileage radius did you use in the autotrader search?

Post the web link so we can all see for ourselves.

If it sounds like I doubt your claim, I do. So prove me wrong. Show all of us one city with 4,600 used hybrid vehicles for sale, 1,200 of which are Civic Hybrids. And remember, you said "near" your city, and ONLY on autotrader.com.

joe131 · June 2007

go to autotrader.com

1stpik · June 2007

I did. Autotrader.com doesn't offer a search for hybrids. Autotrader.com doesn't list the "Civic Hybrid," only the "Civic."

That's why I'm asking for the web links that you cite in your previous post. The one that shows 4,600 used hybrids for sale "near" one city, and the one that shows 1,200 Civic Hybrids for sale "near" that same city.

Just copy and paste the web address in your next post.

joe131 · June 2007

if you want to nitpick, why not include my $2,100 income tax credit in the equation?

"Someone posted earlier about how those who pay Alternative Minimum Tax (AMT) don't get to take the tax credit. It turns out that even if you don't pay AMT, you may not get to take the full amount of the credit.

The San Francisco Chronicle published an article recently on this titled "Hybrid Tax Credit Bait and Switch". The only way to check on how much of the credit you'll actually get is to calculate what you'd owe under AMT, even if you're not subject to paying the AMT. Your famiy income, the size of your family, and the number of deductions you already take are all issues here, so it's not one size fits all.

I doubt that the Ford dealers are going to mention any of this to customers. Notice how they say that ALL customers who buy a hybrid from Ford in 2006 are eligible to claim a full credit on their 2006 return. Not that Toyota or Honda dealers mentioned it, either.

Caveat emptor..."

(from that other Edmund's forum)

gagrice · June 2007

I show 1184 used Civic Hybrids on Auto Trader. Under keyword type hybrid.

I hope your HCH has a long and useful life. A bit of advice, get the extended warranty. You can find a Honda dealer online that will sell the longest Honda care for about $800. It is worth it for piece of mind. The CVT that is commonly replaced will cost about $4800 if not covered. It is not covered under the EPA mandated hybrid warranty.

joe131 · June 2007

Good advice. Is that warranty transferable so when the original owner dumps the car the subsequent owner is covered too? And what things are excluded from coverage? None of the extended warranties cover everything, you know? I found $935 for an 8 year, 100,000 mile, $0 deductible Civic Hybrid extended warranty, but it has to be purchased within the first 6000 miles. I posted the link on the extended warranties forum page earlier today.
My search of AutoTrader showed more than 1200 used Civic Hybrids for sale.

1stpik · June 2007

<<It's not my fault you don't know how to use the Autotrader website.
Look it up.
Hahahaha! No wonder you could not find any for sale.>>

I know how to use the website just fine, which is why I'm calling you out on those numbers -- 4,600 hybrids for sale in ONE CITY, right? And 1,200 of those are Civics, "near" your city, right?

Funny, isn't it, that you only respond to my questions with insults . . . almost like you're trying to avoid justifying your numbers.

Truth is, you can't, because you used the number of Civic Hybrids for sale NATIONWIDE. You just said they were "near" your city to make it sound better.

1,200 HCHs for sale in the entire United States is nothing. You've made my point for me!

1stpik · June 2007

"I show 1184 used Civic Hybrids on Auto Trader. Under keyword type hybrid."

Of course that's what I did. See post above this one.

1stpik · June 2007

You guys keep throwing out specious arguments because you can't argue with facts and numbers.

"I'll bet hybrid owners sell their cars after a year or two ..... I'll bet hybrids are more expensive to maintain ..... I'll bet the batteries and the CVT will fail ..... "

That's called speculation, and it's not a valid rebuttal to facts in evidence.

Saying that the payback is 10.5 years when it's really 6.5 or less, and saying that a hybrid saves $300/yr. when it really saves $500 or more, and ignoring incentives like the $2,100 tax credit ..... all that destroys your credibility.

The title of this thread is "the real payback," and I've done the math for everyone. No matter how you twist the numbers, they won't change.

But keep grasping, and keep spinning ..... and just hope that gas doesn't go any higher! Otherwise, you'll have to admit that

HYBRIDS ROCK !!!

PF_Flyer · June 2007

Let's ease up a bit before this turns into a real fight. We get it. You disagree. Everyone has made their point, multiple times. Not likely that anyone is going to suddenly change their mind and see things differently if the same stuff gets posted just one more time.

This subject has come up before and always seems to end up as a spitting contest that gets the discussions shut down. Let's avoid that fate this time around and move on please.

Thanks for your cooperation and participation.

tch_titanium · June 2007

There are several ways the hybrid battery gets charged. The most efficient way is when the vehicle is 'coasting' or just simply going down a hill. The electric motor turns backwards and dumps current back into the battery...almost free charging. To be sure, this usually doesn't recover all the energy the battery produced so that some of the recharge has to come from the ICE. But coasting is where the extra power comes from.

I did a lot or research before buying a Camry Hybrid. A lot of what influenced me came from a friend in the car business who manages a repair shop connected with one of the biggest car dealers in Mpls/St Paul. He has not seen any issue with Toyota's hybrid system and even used the term 'bullet-proof'. Good enough for me.

More info on Hybrid Synergy Drive:
http://www.hybridsynergydrive.com/en/top.html

tpe · June 2007

You didn't read my scenario. I said if the vehicles were travelling at a constant 65 mph on a level road. The hybrid is definitely not coasting but probably using around 35 hp to maintain this speed. If any charging of the battery is taking place then that must represent an additional drain on the engine. There is nothing to be gained efficiency-wise by adding additional energy conversion steps, i.e. gasoline->mechanical->battery->mechanical as opposed to simply gasoline->mechanical. At 65 mph you have to be going down a fairly steep grade before the car is actually coasting and can charge the battery with no penalty. Don't get me wrong, I think regenerative braking is a great thing. I just think that it provides very limited value for highway driving. However its perfect for city driving.

tch_titanium · June 2007

Well, yes I did read it but I took the liberty of ignoring the very unlikely scenerio of completely level road. Of course I understand what you are saying and I agree with you, but I think your scenerio is too narrowly focused. In my experience driving a Camry, the vehicle is very good at keeping momentum down even the slightest downgrade, and charges the battery as it does so. I don't have to be going 65 and down 'a fairly steep' grade.

joe131 · June 2007

a 5% grade is fairly steep. that's what it takes to coast in gear and maintain 65 mph

tch_titanium · June 2007

Sure, pure coasting would be great in any car, but in HSD it's not just pure coasting or braking that charges the batteries. It's also deceleration after cresting a hill...and trust me the hill does NOT have to be steep.

tpe · June 2007

It's also deceleration after cresting a hill...

Why are you decelerating after cresting a hill? I understand that you are easing off the throttle, but that's not the same as decelerating.

I want to make this clear. I'm not a hybrid basher. I am pro EV and see hybrids as an evolutionary step. The next generation of hybrids will be significantly better than today's hybrids because battery technology will allow for faster charging. Why is that significant? The current hybrids can only utilize a fraction of the amount of energy that is available from re-generative braking. The next generation of batteries will have faster re-charge capabilities, which will allow for the vehicle to more fully recover it's kinetic energy that is being lost due to braking. In a couple of years hybrids will be considerably more efficient than they are today.

kdhspyder · June 2007

I opened this discussion, which I thought had been killed last year and it's like stepping into a time warp. We're back in 2003 again and suddenly the new Prius bursts on the scene and all the world wants to know "..is it worth to buy it for the gas savings...?"

NO!!!

It's never worth buying it for the gas savings - except in my case, maybe. Buy a 3-4 y.o. used Sonata or Corolla or Focus. Do not ever buy a new car and ask if it's worth it. It's a depreciating asset that at some time in the future will be worth spit.

OK now we're finished with that subject.

Oh... you want a new vehicle and have the choice to buy ..
a TCH or Camry 4c ICE
a FEH or an Escape ICE
a HCH or a Civic ICE
the future
Yukon 2-Mode or a Yukon ICE

YOu will pay about $3000 more for a hybrid than an ICE vehicle. You will save about $600/yr in fuel @ $3/Gal. It doesn't matter which hybrid you choose ( the proof is available after class for curious students ). So here is your basic question.

Do you want the money to flow to an oil company and it's questionable partners?
Do you want the money to go to an auto company.

You will spend that $3000 over 5 years. You decide who gets it. You can't hide from it except by driving less, staying home or taking mass transportation.

OK that subject is complete.

Next...

Prius vs ?????? ( there is no ICE equivalent - brilliant marketing/product placement )
Batteries.... puleeze

kdhspyder · June 2007

You didn't read my scenario. I said if the vehicles were travelling at a constant 65 mph on a level road. The hybrid is definitely not coasting but probably using around 35 hp to maintain this speed. If any charging of the battery is taking place then that must represent an additional drain on the engine. There is nothing to be gained efficiency-wise by adding additional energy conversion steps, i.e. gasoline->mechanical->battery->mechanical as opposed to simply gasoline->mechanical. At 65 mph you have to be going down a fairly steep grade before the car is actually coasting and can charge the battery with no penalty. Don't get me wrong, I think regenerative braking is a great thing. I just think that it provides very limited value for highway driving. However its perfect for city driving

Yes...and NO.

You are correct that at a constant speed of say 65 mph on a level highway that about 35 hp are used to drive the front wheels.
..but every ICE is way over spec'd in terms of hp. In fact the 1.5L Atkinson cycle Prius engine has about 75 total hp which when cruising is split between driving the wheels ( 35 hp ) and driving the generator ( MG1 ). Now the computer can decide whether the output from MG1 needs to go to the wheels such as in a sudden upgrade or in passing or whether this out put can be stored in the batteries for future use.

In every other ICE the extra horsepower ( 270 hp -35 hp = 235 hp ) is just wasted in burned fuel that's not doing anything most of the time.

Now step two..
In the HSD system the computer oversees the charge on the battery pack and avoids to get it too charged up or too dimished. When the ICE has been in operation for a while splitting its output and chargine the battery on the fly at some time thereafter the battery is 'full' ( it's not but that's intentional ). The computer then tells the battery to discharge and drive the e-motor. It also tells the ICE to stop spinning at say 1500 rpms and take a rest going to idle at 950 rpms....on the fly at 60-70 mph. It's sort of like cylinder deactivation.
Upgrade --> kick back in
Downslope --> take a break
Passing --> kick back in
It's seamless.

This is part II of the 'charging equation'
Part I of course is the Regen braking which as you correctly note is very likely limited by the technology of the batteries. Right now it's about 30% going back.
Part III is very subtle, as noted by tch_titanium priorly. When the computer senses a deceleration ( foot off the GO pedal ) it switches the e-motor ( MG2 ) to become a generator and makes the front wheels which are rolling in any event drive the generator to recharge the battery. The pentup kinetic energy in the entire vehicle is then driven through the wheels to the battery....up to it's limit.

During this time the ICE is..
..turned down to idle if the speed is over 41 mph
..turned off entirely if the speed is 41 mph or less.
This is a HUGE part of the fuel savings.

The total fuel savings come from 3 main areas
1) complete ICE shutoff at a dead stop
2) ICE only running at idle speed while at full highway speed
3) ICE at idle or shutoff during every coasting period.
The only way to save fuel is to turn the ICE down or off.

Here is a good link for the mechanically inclined on how the PSD and power sources work under different conditions:
What's happening as I drive my Prius

tpe · June 2007

In every other ICE the extra horsepower ( 270 hp -35 hp = 235 hp ) is just wasted in burned fuel that's not doing anything most of the time.

That's a myth. A vehicles's unused horsepower does not represent wasted fuel. You can not conclude that a vehicle rated at 135 hp will burn less fuel than one rated at 270 hp when both engines are producing 35 hp. Take a 1.5L engine rated at 75 hp and throw a turbocharger on it. The horsepower/torque have probably gone up by 50% but it won't be burning any more fuel when producing 35 hp. I believe the Saturn Sky redline actually has a higher mpg rating than the regular version. One of my vehicles is a BMW 330 (3.0L). It's mileage rating is just as good as the 325 (2.5L) despite a 20% increase in displacement and 25% increase in power. Obviously there are a lot of cases where the more powerful vehicle gets considerably worse mileage. I'm simply saying that equating higher hp to reduced efficiency is an invalid assumption.

What kind of mileage does a Prius get at 75 mph, which is the posted limit on many highways? I guarantee there's not a lot of regeneration going on at that speed and I'm not about to drive slower than the flow of traffic.

kdhspyder · June 2007

Thats not what I said.

What I said is that ALL ICE's when cruising only need about 35-50 hp. Nothing more.

Take the Accord 2.4L 4c which is probably the smoothest and best engineered 4c out there now. It's rating are 166 hp @ 5400 rpms and 160 lb-ft @ 4000 rpms. At normal cruising speed of about 1900 rpms this engine may only be turning out 120 hp. Why then does it have 166 hp? And why if it only needs 35 hp to maintain a 65 mph speed does it have to turn out 120 hp? Why can't the Accord just have a 1.3L engine iso a 2.4L. It doesn't need to burn the fuel that a 2.4L engine does in order to maintain a constant speed on the highway.

Because it wouldn't sell. It would be a dog in every other metric that buyers measure; startup, acceleration, climbing, etc. It needs an Otto cycle gas engine with enough oomph to serve all these other needs but it's way way over spec'd and wasteful for cruising at 65 on the highway.

What I'm saying is that you don't need any size engine larger than one large enough to get you 35 hp to drive the front wheels. A 3-spd 1.0L engine will do. Anything larger is wasted while cruising.

So here is the solution: It's the same source as above created by an engineer to explain the inner workings of the Prius and HSD.
Prius drive components explanation

kdhspyder · June 2007

What kind of mileage does a Prius get at 75 mph, which is the posted limit on many highways? I guarantee there's not a lot of regeneration going on at that speed and I'm not about to drive slower than the flow of traffic.

Different strokes and all ... 75 in most places in our area will lose you your license. However on I95 N & S the normal speed is about 85 mph. A Prius will get about 42-45 mpg on a dead flat. There is no 'regeneration' from braking at this constant crusing speed but there is still a split of the ICE output to the wheels and to the MG1. That happens all the time. The HSD computer still decides how much of the flow from MG1 needs to go to maintain speed and how much should go to keep the battery in its prime SOC. Then even at 75 mph when the battery reaches its 'full' point it will be discharged and the ICE will take a break and cycle down to idle.

All vehicles suffer at 75 vs 60 due to the effect of drag. All vehicles will be less efficient and burn more fuel to overcome the increased drag.

It appears from SOP measurements using the internal MFD that the effect of drag at 75 and higher puts the ICE in use about 10% more often, it uses 10% more fuel, so it cycles down less often. A scan tool will be much more accurate of course.

tpe · June 2007

If Toyota figures out a way to make the 1.5L engine in the Prius more efficient I can assure you a natural by-product of this increased efficiency will be increased horsepower. I don't understand why people feel that power and efficiency are contradictions, enemies of one another. If most vehicles operate using 35 horsepower the majority of the time then the engineers should design an engine that is the most efficient at producing 35 horsepower. It sure won't be an engine rated at only 35 horsepower because no engine is most efficient at it's max output. So this extra unused horsepower is not wasted.

While I have no way to prove this I suspect that if you hooked up the Toyota 1.5L and Honda 2.4L engines to a dynamometer and had them both outputting 35 horsepower the difference in fuel flow would be trivial. So whether or not it's over spec'd is irrelevant. If it's not burning more gas it's not wasteful.

kdhspyder · June 2007

You still miss the point.

Your original question was 'what about cruising at 65 mpg on the HWY?' We agreed that a vehicle only needs about 35 hp to do this.

The Prius uses a 1.5L 70 hp Atkinson cycle to achieve this.
The Accord ( just as an example, it could be any vehicle ) uses a 2.4L 166 hp Otto cycle.

The Prius output at 65 mph is about 50 hp.
The Accord output at 65 mph is about 120 hp.

The constant in your scenario is that the vehicles have to operate and cruise at 65 mph on the Highway. What occurs in your scenario? The Prius burns less fuel due to its smaller displacement and more efficient cruising cycle. Yet, even with the smaller displacement and more efficient cycle the Prius still generates excess power some of which is stored in the batteries.

It just works as designed. The proof is in the Hwy fuel economy ratings - revised.
Prius 43 Hwy = 23.25 Gal/1000 mi driven ( GpK )
Accord 31 Hwy = 32.25 GpK

OK use the Corolla 1.8L VVT-i
Prius 43 Hwy = 23.25 GpK
Corolla 35 Hwy = 28.57 GpK

It, the Prius, simply burns less fuel to accomplish the same purpose. It works. It can also work better. Everything can. See the third installment of this blockbuster at a theater near you in Oct 2008.

1stpik · June 2007

You identified the REAL reason smaller engines burn less fuel than larger ones. It's not the horsepower, but the size.

A 1.5 litre engine naturally burns less than a 2.4 litre because it has 0.9 litres less cylinder space. The horsepower rating means little. The torque does factor in slightly because higher torque allows the engine to rev lower during acceleration and hill climbing than a smaller engine with less torque. However, overall the smaller engine will ALWAYS burn less fuel simply because it can't burn as much as a larger engine.

So, the analogy is correct that a large, powerful engine only uses its capacity on acceleration and wastes it during cruise. But it's not the horsepower the engine is wasting, simply the physical space within the cylinders and the gasoline that keeps squirting into them as the engine runs.

This is why some high-end cars now have 8-cylinder engines that will shut down four cylinders during cruise to increase efficiency. The engines use full power on acceleration, and 1/2 the power during constant speed driving -- a hybrid system without the need for batteries.

tpe · June 2007

The Accord output at 65 mph is about 120 hp.

I have no idea what you are talking about. The horsepower being produced will be what is required to maintain that speed. It has everything to do with the vehicle and almost nothing to do with the engine in the vehicle. It will be different depending on whether you're going downhill, level or uphill. I have a 2003 Accord 3.0L rated at 240 hp and 212 ft-lbs of torque. At 65 mph the engine is turning at 2,000 rpms. So the maximum amount of horsepower I could possibly be producing is (212*2000)/5252 = 80.7 horsepower. A couple things. The max torque occurs at 5,000 rpms in this vehicle but regardless since I am applying very little throttle I'm using a small fraction of the available torque. When I'm cruising down the highway at 65 mph I'd be surprised if I'm using more than 80-85 ft-lbs of torque, which comes out close to 35 horsepower. I could put the Prius engine in my car and it would still require the same amount of horsepower to maintain 65 mph.

kdhspyder · June 2007

Agreed. It's the displacement, tuning and optimal use of the cylinders that save the fuel...or not.

However the V8's w/DoD and the V6 on the Ody with cylinder deactivation still produce an excess amount of energy/power that's unneeded at a constant cruising speed. IOW they burn unneeded fuel even in their most optimal conditions.

tpe · June 2007

You identified the REAL reason smaller engines burn less fuel than larger ones. It's not the horsepower, but the size.

It takes a certain amount of energy to move a vehicle, regardless of its engine size. There is a fixed amount of energy in a gallon of gasoline. For your statement to be valid would require for small displacement engines to be more efficient at converting the chemical energy in gasoline into mechanical energy. That is just not the case.

kdhspyder · June 2007

Yes your calculated estimation seems more accurate in the absence of the Accord torque/hp curve, which I couldn't find. Tks.

kdhspyder · June 2007

Yet take the case of the Prius vs the Corolla.

Here there is a 1.5L Atkinson cycle driving a larger heavier vehicle on the highway more efficiently then a 1.8L drives a smaller lighter vehicle.

Less gasoline is being used pound for pound in the Prius. Is it the tuning? Is it the recapture of kinetic energy? Reduced losses? A combination of all three?

plekto · June 2007

YOu will pay about $3000 more for a hybrid than an ICE vehicle. You will save about $600/yr in fuel $3/Gal. It doesn't matter which hybrid you choose ( the proof is available after class for curious students ). So here is your basic question.
***
I'd like to make a point, though, which is that it's not as clean an equation as this. The 5K(typical price differnece over, sat, a Corolla or Fit) more expensive Prius also has more interest on the loan, more expensive insurance, more expensive registration fees, and of course the extra money tied up with the larger monthly payment.

So it takes a tad longer to break even. Closer to 8-10 years if you run the math.

Now, the rest of your points are valid - it's a bad thing(tm) to be giving a dime more to the oil companies than we need to. There are real reasons to buy a hybrid, but the Prius is about to have a lot of company by the looks of it.

The real killer, though, will be the CDI Hondas in a year or two as well as the hybrid Fit. Expect real-world results simmilar to the Insight did(which by no coincidence shares the same basic platform as the Fit). For $18K.

My money, though, is on the CNG Civic. With a fuel cost of .90 cents a gallon equivalent if you fill it at home(the filling device has some incentives on it which may help defer the cost some), and virtually no pollution, it's the real deal. Environmentally friendly, saves money, and tells OPEC where to stick it. The only gripe that I have is that it wasn't re-worked properly to fit two or three smaller tanks to double the range. There's a big wasted space, for instance, where the gas tank used to be and they suck up half of the trunk instead.

P.S. The best alternative would be to make the car a real hybrid and have a small turbine generator connected to a purely electric drivetrain. All the engine would do is recharge the batteries. Remmber - the 35-40hp a car requires to maintain highway speed is based upon a typical engine's only being 30% efficient. Electric motors are far superior and result in less energy loss. So you need a smaller amount of energy per mile to be put back into the system(most small turbines are twice as efficient as 4 stroke engines as well if they are run purely for generating electric power)

joe131 · June 2007

Using your own figures (for the 4 cylinder Accord motor) of 160 max torque, even if that max was produced at 1900 rpm the horsepower produced at 1900 would be ONLY 57.9 HP. How you came up with 120 HP at 1900 rpm must be voodoo arithmetic.
Now if torque at 1900 rpm is really only 100 ft. lbs., then horsepower at that rpm would be 36.2 HP.

plekto · June 2007

No, you just have to look at the dyno graphs. It's not an electric motor, afterall...

joe131 · June 2007

Please post the dyno graphs if you have any.
What torque is that motor making at 1900 rpm? Do you know?

kdhspyder · June 2007

I was only using it as an example and admittedly guessing as I noted. A better estimation was given by tpe in his calculation..as I noted.

Next subject.

kdhspyder · June 2007

I'd like to make a point, though, which is that it's not as clean an equation as this. The 5K(typical price differnece over, sat, a Corolla or Fit) more expensive Prius also has more interest on the loan, more expensive insurance, more expensive registration fees, and of course the extra money tied up with the larger monthly payment.

So it takes a tad longer to break even. Closer to 8-10 years if you run the math.

Yes as I mentioned in the first post it is always better from a total 'cost of transportation' pov to buy a less expensive vehicle preferably a good 3-4 y.o. used vehicle. This has nothing to do with 'fuel economy', it's only a personal preference on what you'd like to drive. An 8-10 y.o. Lexus 300 may be a better transportation fit for some while a new Civic or Cobalt might be for others while a small 5m Tacoma 4c Reg Cab might be for others.

My comparisons were between vehicles where there was an ice/hybrid twinning. The difference is about $3000 in each case. There is no valid ICE vs hybrid comparison on the Prius it's a stand alone vehicle. The closest ICE competitor to it is a Matrix ( from a utility pov ) or Jetta TDI ( from a fuel economy pov ).

punkr77 · June 2007

I was thinking about Hybrid's while sitting in a dealer purchasing a new car this week. I don't think 90% of the people who buy hybrids do so because they expect to get their money back in the form of higher MPG. (The 10% who do didn't bother to do the math) I think it's mostly a political or fashion statement.

The Prius is uber popular because it looks different so people know you're driving a hybrid. The civic, camry, accord hybrids are less popular because the average Joe won't know the difference unless he notices the prominant hybrid badges.

I don't see myself ever owning a hybrid while other vehicles are available. I like my cars to be sporty, preferably with big engines putting out lots of horsepower. In the end, I'm guzzling less gas in my V8 Mustang than the vast majority of Hybrid owners. How can that be? I only drive about 6,000 miles a year. I walk or ride my bike to work, my wife does the same.

1stpik · June 2007

Punkr77 certainly has the best solution -- just drive less. My parents are the same way. They drive about 5K miles per year, keep their cars forever (mom's minivan is 8 years old with 42K miles), and couldn't care less about the price of gasoline.

On the other hand, I drive 25K miles per year, so gas prices really p. me o.! However, I drive that much for reasons other than you might think.

I have a short commute to work -- 12 miles each way. I live 5 miles from Wal Mart and Home Depot. So where do the miles come from?

Road trips.

I visit my parents 2-3 times per year. That's a 1,000 mile round trip. Grandparents, 2,000+. I also drive to all my vacation destinations instead of flying.

This isn't a gas thing. I got fed up with the airlines long before the WTC attack and the new security restrictions. When American Airlines left me stranded in Miami for 9 hours -- lied to me, said "2 hours," then said, "2 more hours," then said (you get the picture) -- I swore off airlines and their corrupt business practices and started driving everywhere.

No more flight delays, cancellations, bumps, lost luggage, rude treatment, etc. And the time of driving vs. flying isn't bad when you factor in drive time to the airport, wait time at ticket desk, wait time in security line, wait time for flight, actual flight time, wait time for luggage retrieval, and drive time from airport to hotel. Also, figure in the cost of airport parking and rental car/taxi fare, and you might find that driving's a better deal.

Sorry to go off on that tangent, but that's how I put so many miles on my odometer. That's why a hybrid works for me.

By driving so much less, Punkr77 certainly has a valid claim to a gas guzzler. However, he's not really burning LESS gasoline than the average hybrid owner, just not burning MORE:

The V8 Mustang averages 18 mpg (revised EPA), while the Toyota Prius averages 46 mpg. So his 6,000 miles per year burns the same amount of gasoline as a 15,000 mile/yr. Prius owner.

texases · June 2007

Why do smaller engines get better mileage? Lets assume same car, different engines, otherwise equal (including basic engine philosophy)(put a 50 lb weight in the trunk of the I4). Say you could have a 2L I4 and 3L V6 with everything the same except number of cylinders. At the same speed both engines are putting out the same hp. Power output only follows the dyno chart at full throttle, not at part throttle, and that's the key. The V6 is not working as hard (the throttle plate is less open) than the I4 when putting out the same power, so the intake manifold vacuum is higher with the V6. Therefore, the true compression ratio is lower, leading directly to lower economy. Another name for this is "pumping losses" - the wider open the throttle, the lower the pumping losses. That's how the V8 and V6 cylinder deactivation technologies work. They increase the required throttle opening to produce the same hp out of half the cylinders, decreasing pumping losses. That's also why tall gearing works, it requires a wider throttle to put out the same power at a lower rpm. Of course, they can't do quite as well as the equivalent 3- or 4- cylinder because of all the extra equipment they have to spin around, along with the loss of heat during the comression cycles on the deactivated cylinders.

tch_titanium · June 2007

"I was thinking about Hybrid's while sitting in a dealer purchasing a new car this week. I don't think 90% of the people who buy hybrids do so because they expect to get their money back in the form of higher MPG. (The 10% who do didn't bother to do the math) I think it's mostly a political or fashion statement."

I might have agreed with you 1-2 yrs ago. I am one of those that expect to save money...and I did do the math. I've been watching hybrids for a while now waiting for the price differences to be smaller. The Camry has made the delta practical enough for me to make the purchase. I think I made the right choice. Take a close look if you care to...the Camry Hybrid is less than $2K more than a comparable XLE. I drive 20K/yr to work and will save ~$500/yr on gas. I don't buy new cars very often and will probably drive this thing into the ground. (My other car was a 95 Camry with 200K+ and counting). It was an easy choice for me.

I'm no tree-hugger, hyper-miler or interested in making political/fashion statements. Just a guy driving to work and saving a little $$ on gas. So stuff it.

tpe · June 2007

Do you think that the Toyota Camry, non-hybrid, would get better mileage if you took out the 2.4L and replaced it with the 1.5L in the Prius?

Smaller engines are not inherently more efficient. All engines have a power range where they are operating at their peak efficiency. For smaller engines this occurs at a lower power output. Look at gas and diesel generators. The larger ones produce more killowatt-hours of power per gallon of fuel burned. If smaller was really more efficient it would make sense to use two small generators as opposed to one large generator. It doesn't make sense.

Your pumping loss explanation implies that engines operate most efficiently at full throttle. That doesn't sound right. Also, there are efficiency losses incurred due to higher rpms. The larger displacement engines can produce more torque allowing them to produce the same amount of power at lower rpms, sometimes significantly lower.

m6vx · June 2007

Please post the dyno graphs if you have any.
What torque is that motor making at 1900 rpm? Do you know?

There is no one answer.
For example:
1) flat and not accelerating, 1900 rpm
2) uphill and accelerating, the instant it's at 1900 rpm

Which one do you think is producing more torque?

(Hint: the one where your right foot is touching the floor! :P )

HP / torque graphs show MAXIMUM HP and torque.

punkr77 · June 2007

I stand corrected. I've never really looked into the Camry Hybrid (apperently not that many others have either since it's being dropped from the lineup due to poor sales). Don't get me wrong, there's nothing wrong with hybrids if they fit your wants and needs. But the payback period makes the extra money saved from consuming less gass much longer than most would expect.

You have to figure either the interest paid on the extra loan amount (which will vary with your credit rating and term). If you pay cash, you have to figure the interest you're giving up if you had purchased a comparable gas vehicle and invested the prioc difference (which would depend on the markets and how you invested it).

Incentives will also impact it. You're probably more likely to get closer to invoice pricing on a non-hybrid than a hybrid. Again, that will depend on which model you're looking at and where you live (LA vs Midwest).

Also, there's the factor of how long you expect to keep the car and resale value.

Then there are the things you can't really predict like what gas prices will average over the life of the vehicle (I'd guess higher, but that's just a hunch) and long term repair costs on the more advanced hybrids. The oldest hybrid here in the US is now turning 8 years old, and I'm not sure what they're long term repair histories are like compared to their all-gas equivalents.

tch_titanium · June 2007

Yep, a lot of factors and you could drive yourself nuts trying to figure it all out. But I'm past that now and am just enjoying the car...and still very glad I made the choice.

By the way, you're confusing the Camry with the Accord. The Honda Accord hybrid is the one that is going away (but sounds like it will be replaced by some other type of hybrid...Honda would be crazy not to). Camry just got started.

Hybrids the Real Payback

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