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The Math Behind the Hybrid Hype
markmcb writes "OmniNerd has posted a thorough mathematical analysis of purchasing a hybrid vehicle that dispels much of the hype associated with this modern buzz word. The author considers all of the major factors to show just how much money a hybrid vehicle will or won't save you. In the end, it seems the only real winner after a hybrid purchase is the environment."
> the only real winner after a hybrid purchase is the environment.
That is to say, everyone and everything on the planet.
Here in Europe the fuel prices are vastly different. Where in the US the price this year was between 37.9 and 26.82 UK pence / litre, in the UK it is currently 91 . So you would have to multiply the savings in petrol by 3 or so.
Fortunately in Europe we also have a system of public transport which most environment minded people (like myself) prefer to use rather than pretend we are doing our bit through the purchase of a new car.
Mouse powered Chips, Open source Processors and Lego
"In the end, it seems the only real winner after a hybrid purchase is the environment"
And that isn't enough?
My Sig: SEGV
umm...
buying a new car is almost -always- a losing proposition, financially. If money is a concern, a 3-year-old Accord or
Camry is probably the best way to go.
I bought my prius to replace my 15 year old celica. I didn't buy it to save money, I bought it because it was an interesting/cool car in my price range. The fact that it is a hybrid entered into MY purchase equation but it wasn't the only reason.
The fact that I've gotten as much as 66.5 mpg (after a 50 mile round trip commute) is just icing on the cake.
My dad works for a local government and was required to investigate the use of hybrid vehicles for use in his department, as a form of gasoline reduction measure, to save money. However, since this local government doesn't have to pay taxes on the gasoline it purchases, it can get it for very cheap. He also found that it would take well beyond the life of the vehicle to become profitable.
I think it's kind of unfortunate, really, why hybrids cost so much more than conventional vehicles. The tax incentives in this case were of no use, as I said, because this agency didn't pay taxes.
This data does not take into account someone who is already willing to lay out 20-30K on a SUV and deciding to switch to a hybrid instead. It has been long obvious that hybrids were not yet the most cost efficient way to travel. Though if you already own a 30K SUV, and you trade it in for a hybrid, you will see savings. Take these statistics for what they are. The most interesting point being in figure 13 where it seems with gas at 2.50 a gallon, a car that gets 50 - 60 mpg would have to cost less than 13,000 to be the cheapest new bought transportation.
quis custodiet ipsos custodes
Fundamentally, there is a problem with the way the US is underpricing fuel. In Europe prices are much higher (US$6 per gallon is typical) which provides a financial incentive to create cars with lower fuel consumption, primarily though making more efficient engines.
Until the US starts to tax gasoline products in order to encourage fuel efficiency, then the US will continue to drive around in inefficient gas guzzlers. Heck, they would in Europe too if the tax regime wasn't different.
Never email donotemail@WeAreSpammers.com
He compares the Prius to a Corolla; really it's closer in quality and size to a Camry, which is much closer in price.
Also, the value retention part of it is key in treating it as an investment, but "OmniNerd" doesn't do that, he's just calculating the change in monthly payments. That completely invalidates the monetary comparison from the start.
I.e. the "Math" here is off base, by quite a lot.
Plus, my '05 Prius is very fun to drive, wouldn't trade it for just about anything (well, maybe one of those $40,000 sports cars...)
Energy: time to change the picture.
It is the whole model that is screwed-up.
Getting rid of the cars is the only solution. There is no way on earth (or in hell) to provide three tons of scrap (and the energy needed to move them) to each human on the planet.
Anyone who purchases a hybrid without doing at least a really basic cost analysis is an idiot.
We purchased a Prius back in June. We knew that unless gas stays at like $3 or $4 a gallon, it wouldn't really pay off (and then Katrina hits, and we actually paid $3 a gallon for a few weeks).
It's not a cheap car, but fully loaded, it really wasn't that big a difference for us compared to, say, and Accord. And it gets better mileage. You can run the A/C in stop-and-go traffic with virtually no gas consumption (the gas engine cycles on for 30 seconds every five minutes or so).
Plus, it's incredibly geeky. What's not to love? We've even been able to fit a lot of stuff in it for weekend trips (suitcase, assorted other bags, cameras, etc., plus a stroller, pack-and-play, and, of course, the baby), even leaving the back seat pretty much free of extra boxes or bags. You'd never think there was so much space to look at it from the outside.
Bottom line: Don't buy it to save money. Buy it for the clean air impact, and especially to support the longer-term development of hybrid technology. Imagine if this were in *every* Toyota car -- their CAFE numbers would probably be up in the 30s or 40s (it's probably in the 20s right now).
[it's also displaced our Explorer as our primary errand-running car, which is certaily helping *our* bottom line somewhat...]
Nice analysis, but like most of these type of analyses, they ignore some important factors:
Environmental cost of manufacturing NiMH batteries
$ Cost of replacing batteries at end of useful life (which is likely before the vehicle's useful life is over)
Environmental cost of disposal of NiMH batteries (likely 2 sets per vehicle during useful life, 100 pounds+ each set) That's a lot of heavy metals to dispose of.
Why must hybrids be the only product to prove themselves economically? If people bought stuff based solely on price/performance, we'd all be only eating bread, drinking water, living in small shacks, and driving white 15-year old Honda Civics. Boring.
I buy lots of things that don't make economic sense. I have expensive sports equipment like road bikes and scuba gear. My computer has lots of fast parts that I don't really "need".
Maybe there's more to things than just what your ROI is.
This math does not take into account the ass factor. There are a lot of chicks that are hip to this save the rain forest crap and they may be more inclined to open up for a guy who "cares" about the ice melting. Think of these tofu-eating broads as an untapped market and get yourself some rubbers and a set of 21 inch rims on your Prius and you're ready to go. You might not even have to use rubbers with these girls if you play the latex is bad for the pandas card.
if you're the type of person that gets a new car every 5-7 years or 100,000 miles, whichever comes first, then no, you're not going to save money by purchasing a more expensive car. If, on the other hand, you're the type who takes care of your vehicle, maintains it, maybe even makes a few repairs on your own rather than taking it to the shop (or neglecting problems outright), with the hopes of getting 10-20 years (and 250,000+ miles) out of your vehicle, then you might actually save money in the long run, assuming roughly equal wear-and-tear and part replacement needs for hybrid and conventional vehicles.
My personal take on it is that hybrid and fuel-cell systems are still flawed due to their continued reliance on fossil fuels. An all-electric vehicle would be ideal, and indeed we have our electric motor science down pat. What we lack are effective battery systems -- pound for pound, gasoline contains far more energy than our best batteries. Until we can improve our electrical energy storage, we are limited to either having a very small "gas tank", in which we'd have to stop and recharge every 50 miles or so, or a very large, heavy, slow vehicle carrying a ton or six of battery cells in order to extend the range of the vehicle. Neither is a generally viable solution.
The car manufacturers are reluctant to further research these alternate systems, I think, due to the fact that if you take away or reduce the internal combustion components of an engine, you reduce the stress and heat experienced by the engine, which means the engine parts fail less often, which means they sell fewer new cars. No company is going to deliberately research ways to reduce their profit.
Actually, the analysis is based on MSRP, but I doubt anyone pays MSRP anymore. In fact, I've two Honda civics, one standard (for my wife), and one hybrid. The hybrid came with more options standard and ultimately I argued the price down to about $1400 of the normal Civic. I've made that up between tax breaks and gas savings, but better still it's ULEV that can go 600 miles on a tank of gas. That's pretty good.
As far as maintenance costs -- both have been excellent.
The article seems to be assuming that Gas prices remain constant through the life of a car. Anyone believe that? How about the same calculations assuming a 10% per year increase in gas prices (which they were this year before Katrina).
from the article:
Gas-electric hybrids are the most fuel-efficient passenger cars on the road and ecologically there isn't a more viable option. Until something big changes, though, the industry-high efficiency can't economically offset the steep sticker price.
This is quite a sweeping claim, and one that I would contest. The VW Jetta TDI (diesel) gets consistently 55-60 mpg -- about as good as the best hybrids out there. What's more, diesel fuel uses less fuel in its manufacture than regular gasoline, meaning that the "embedded fuel" is significantly lower.
I tend to agree that much of the hybrid talk is hype and that getting 25 more miles out of a gallon of fuel does not make your car "green". What's much more, though, is the idea that hybrids get better mileage than any other cars on the road. Diesels, particularly some of the models by VW and Audi (in Europe, at least), prove that efficiency is more than just fancy technology.
The batteries in the Prius are not lead-acid, as another poster pointed out. They're NiMH. In addition to that, they are warranted for 8yrs/100k miles, and expected to last the lifetime of the car without replacement, so it's unlikely that there will be much more than one battery pack per car lifetime on an average basis.
Toyota recycles them completely, chemicals, metals, case, wiring, etc... and pays a $200 bounty to encourage people to do so. Their recycling program has been in place since the Rav4 EV, so it's a fairly mature process by now.
I'm guessing the reason the article's author chose to structure things in terms of a bunch of new cars (hybrid and not) vs. a 1999 Honda Accord is because the author owns a 1999 Honda Accord. This alone gave the article an unnecessary slant. The basic conclusion -- that hybrids are more expensive to own on an installment plan than comparable standard and diesel cars -- is valid, but the gratuitous comparison to a six-year-old car exaggerates the differences by making everything a bad proposition compared to his 1999 Accord.
Heck, how do I get a 1999 Accord for $4000 anyway? By lucking out at an auction? By buying one off my favorite aunt? Last I checked in my area, 1999 Accords in decent condition fetched at least 50% more than that even through private sellers. Use of honest numbers for comparison woud help. That and factoring in repair costs. I doubt his 1999 Accord is still under warranty, making average repair costs more expensive.
Also, his favorite new-car-to-new-car comparison was between the Prius and the Toyota Corolla. The Corolla, though bigger for 2006 than past models, is a compact and the Prius is generally regarded as mid-sized, Edmunds database notwithstanding. And comparing a Prius to the stripped-down base Corolla is also a bit dishonest. The base Prius is equipped comparably to one of the upgraded Corollas that sell for $15,000-$16,000, not to ths stripped $12,000 model. Want a decently-equipped Toyota for $12,000? Go look at the Echo or whatever they renamed it. That's even smaller.
The TCO advantage still belongs to the quality non-hybrid gasoline and diesel vehicles, but not as much as indicated here. And as gasoline prices pick up again this spring and likely top $3/gallon for good, the smaller-than-stated gap will narrow considerably.
Look at how much toxic chemicals is in a battery. Now factor in that you have to replace the batt every 2-4 years. Not only does it end up costing you more, but you're not doing much besides thinking you're helping.
Interesting...I've had my Prius for over 2-1/2 years and over 75,000 miles, and I haven't had to replace the battery yet. The battery carries a 100,000 mile warranty, and is designed for the life of the car.
Where does the 2-4 year number come from?
Government's idea of a balanced budget: take money from the right pocket to balance...oh who am I kidding?
They only burn less because they usually have a higher utilisation. And they only always have higher utilisation during rush hours.
e.g.
http://www.futurepundit.com/archives/002197.html
Conventional mass transit isn't the answer. Packetised mass transit is...
Deleted
Hey there,
I'm looking for a car and really wanted a Prius. We test drove on last weekend and I loved it (was ready to put down my deposit). One problem though, my wife (6'4") was too tall to sit in either front seat of the Prius. This wasn't just "Wanting more room". She couldn't sit there at all, without a pretty major contortion of her legs just to get the door shut for a 5 minute test drive.
Here are some real stats: Toyota's happily made the Prius about 300 pounds heavier than the Civic Hybrid, so that it enters the "midsize" category of cars. See, cars are categorized by weight, not size. As it turns out, the Civic is larger in every external dimension (H,W,D) than the Prius, and yes - my wife fits in one just fine.
I actually have no problem with the Prius, but it's funny that you get nearly $1000 more tax incentive with the Prius than the Civic as of Jan 1, 2006, because the Prius compares better to it's "weight class/midsize" than the Civic Hybrid compares to it's "weight class/compact". For safety & size, I'd go with the civic.
One more thing - a well equipped Civic with 6 airbags standard (and I would assume Corolla, but haven't done the research) will get 40mpg highway and cost you about $7k less than the Prius.
This is a critical point. Without taking the resale value into account, the calculations are useful only in determining what your monthly payment is-- not what your lifetime cost for the car is.
By my math, if I'd bought a Prius instead of a Civic HX in 2001, I would just now be crossing the point where I was ahead. I would not, however, have that money in hand unless I sold the car. I would have paid out more per month, but I would also get more back on selling.
On the other hand, it's almost never a winning financial bet to buy a hybrid when you already have a working car. New vs. new, a hybrid will just barely edge out a similar but cheaper car over five years or so, but it would have to be a staggering difference in fuel economy to beat out a paid-for car.
And this is a key point that the author overlooked in the economic analysis. It's similar to saying the world's space programs have all been a total economic waste and reaching that conclusion by eliminating all of the economic side effects that have resulted from the technology that went into those space programs. That's a political statement, not an analysis.
The large-scale production of NiMh battery arrays that go into hybrids is rapidly reducing the unit price of these high energy density storage devices. Now, is it really a great lap of logic to think that low-cost high energy density rechargeable electricity packs might find use in other products besides hybrid vehicles once the price is right?
Not only has the price of large arrays of NiMh cells gone down dramatically in a short time, but the early stages of an upramp in large arrays of Li-Ion batteries is beginning as well.
But wait, there's more!
Supercapacitors. Did you know that the regenerative braking system in Japanese hybrids uses arrays of supercapacitors? Again, the technology has been around for a long time, the real issue is price and the price doesn't come down until we get economies of scale and we don't get economies of scale until we get a consumer grade product that uses masses of these devices.
The availability of these high energy density devices at low prices is almost guaranteed to have fall-over effects in all sorts of different consumer markets. Unless you take those significant advantages into consideration, it's really just a snipe to draw a conclusion about the lack of economic value in a hybrid car.
The only reason to buy a hybrid is show other people how much you care about the environment: it's a statement, not an answer.
Okay, mr-stereotypical-SUV-driving-cellphone-talking mcdonalds-sucking-American-corporatist-pigdog, some of us actually do care about the environment.
Very few people can tell that I use all CF lighting in my home and pick my CPUs based on power consumption (Athlon 64 all the way, baby!). My lawn "only" looks healthy, not the bright-chemo-green I could get by dumping fertilizer and weed killer on it. No one but me can tell that I go out of my way and pay more to fill my (SO's) car with B20 biodiesel. That I use biodegradable laundry detergent and non-chlorine bleach. That I manually duplex all my printouts, thus using only half the paper (and for personal use, I'll even do 2- or 4-up per side as well). That I post on Slashdot using 100% recycled electrons.
You can't tell any of those things from a casual observation (well, I suppose if you came into my house you might notice the color of the CFs rather than incandescents). Therefore, I can't possibly have a "oh, look at me saving the environment! Look, look, I care!" motive. Nor can you attribute it (like the FP) to purely financial goals - Some of those save me money, some cost me more. The net gain goes straight to helping YOU breathe better.
Unfortunately, I suspect that more often than not, you have it right. But hell, I'll take even the slight improvement of faux-environmentalists over a proud SUV owner any day.
I've had a 2004 Prius since November 2003. I'm very pleased with my car, and I'll keep it for many years to come, I think. One thing that keeps coming up is that I didn't save any money. What I don't understand is why that focus is applied to the hybrid and not other cars? You can pretty much get a fully functional, well engineered car today for around $12K. So every dollar you spend over that is just for personal taste. When someone buys a $60K BMW, I don't hear people saying "You know, you didn't save any money".
I guess the idea that you might save money with a hybrid casts the image that most people who buy them are out to save money. I'm not. At $24K, the Prius is only a bit more expensive than other cars of it's quality -- but like a BMW purchaser, I would have bought it for even more. BecasuseI think it's cool. I like the idea of using as little oil as I can while still living a convenient and comfortable life. I like the idea of polluting as less. And most of all, I like the idea of voting (with my dollars) for changing technology in automobiles.
So, just want to point out that not everyone who buys a Prius is doing it for a financial reason -- probably not more than with any other car.
Cheers.
I believe that the time is ripe to publish my own findings on this subject.
My research was specific, so my results are too. The bottom line is that if you purchase a Honda Civic Hybrid you save $5,638.32 and 30 hours of your life in comparison with the purchase of a Honda Civic GX.
I've factored in things that most people don't consider, such as:
Oil changes are slightly more expensive for the hybrid Civic, because synthetic oil should be used. However, oil changes are required every 10,000 miles, unlike the 5,000 of the Civic GX.
At least through the end of this year, in California, purchase of an HEV will get you a $2,000 tax writeoff - which boils down to approximately $600 in actual money.
While the initial cost of owning a Civic Hybrid are higher than a Civic GX; the cost OVER TIME is lower, and my calculations take that into account. In order to save money with a hybrid, you'll have to be in it for the long haul, to the tune of about 80,000 miles. At 80,000, you start saving money over a Civic GX.
The battery replacement issue: Yes, this is the big deal that the oil company shills like to bring up every chance they get, but it's really a non-issue. $2,000 to replace the batteries still leaves you with over $5,000 saved. And, I have in my posession (see the link) maintenance records of a Civic Hybrid logging 129,000 miles and never having an HEV battery replaced.
Miles per gallon: It's common knowlege that the EPA mileage on a Civic Hybrid is a bit on the optimistic side. That's why I took my MPG data from actual Hybrid drivers. Note that my numbers are for people who KNOW HOW TO DRIVE A HYBRID - they won't work for your 16 year old son who's trying to drag race the thing at every green light. (and on a related tangent, Hybrids have great torque because acceleration from a stop is heavily assisted by the electric motor - so in a short race, your hybrid might beat a regular Civic. Don't put any money on it, though... I'm not a racer, so I'm not sure)
The good news here (if you can call it good) is that the higher that gas prices go, the wider a gap there is between hybrids and the "normal" kind of car, (whatever we'd call it in this context).
Please let me know if I've made any mistakes in my reasoning - I don't want to fool myself any more than I want to fool the rest of you - so if I've made a mistake (and I often do), I certainly want to be put straight about it. The beautiful thing about this spreadsheet is that you can easily put in numbers that match your situation and see updated totals. Is the price of gas higher or lower where you live? Change it!
http://sonic.net/~montag/hybrid/
I wish I'd had more time to format my results nicer - maybe add some charts or something. But the OpenOffice Spreadsheet which I'm linking you to was really created for my own personal use. I hope it's useful to somebody!
You can run but you can't hide, except, apparently, along the Afghan-Pakistani border.
Papers like these are crowning examples of why economics is not just imperfect, but a fundamentally flawed "science". Cost and pricing, according to economic theory, are supposed to represent actual real-world values of labor and resources consumed to produce something. The fact that economics cannot properly account, even remotely, the degradation of the environment and account for how this will impact us in ten to 100 years means that its recommendations should be taken within a strictly constrainted box.
However, economics has become the modern religion of politics, with its "experts" word taken as golden writ, despite the path of ruination it leads us to. The world continues to ramp up nonsustainable consumption of all resources, especially as China, India, and other countries modernize. The only route to redefining the costs and economic behaviors is government regulation, which is now so passe and under steady assault, both explicitly through increased conservatism, and practically by offshoring all manufacturing in unregulated countries.
Of course Slashdot happily plops shit like this paper on slashdot as the holy scree of the economists, as if that is the end all be all. W00t! Hybrid owners p0wn'd, we're l33t kewl.
please.
Hey, I'm just your average shit and piss factory.
They finished it two or three years ago. They did it together with some funding from the federal government. However, before they even showed it at a car show, another arm of the government had changed the law so that Diesels cannot qualify as PZEV (partial zero emissions vehicles), and so they no longer made sense for the companies to even consider making, as they wouldn't help them make their low-emissions mix of production.
As to Diesels making power, they don't make much power. Power is horsepower, Diesels are low on HP. They make a lot of torque, but due to the gearing necessary due to the low redlines, most of that doesn't make it through to the wheels where it would do you any good. And Diesels only make all that torque with complex turbocharging setups (see the new Mercedes 3.2L tri-turbo engine).
With low-sulfur gas and direct gasoline injection, gasoline engines also don't have to close the throttle plate when you let off the gas. They do quite well on the highway.
As to the 45mpg, it's nice. Do the math though. With Diesel costing $0.50 more per gallon right now, the breakeven point of getting your extra $1K or more back that you paid for that engine instead of a gas one is well outside of 100,000 miles.
Say a gas engine gets 26mpg and Diesel 33mpg. You use 4 gallons per 100 mi in the gas engine, 3 in the Diesel. Gas costs $2.50/gallon, Diesel $3.00. So you use $10/100 mi in the gas engine, $9 with the Diesel. So you save $1 for every 100 miles. To save $1000, you have to drive 1000*100 or 100,000 miles. That's before you pay the extra for Diesel maintenance (particulate filters are the newest extra cost). And yes, I know the Diesel does better than 33mpg, but the gas engine does better then 24 also. The numbers get worse if the Diesel gets 40 and the car 29, which is more on track.
http://lkml.org/lkml/2005/8/20/95
Ahhh, did anyone check the math. It looks a bit off. First he uses a 1.15 multiplier to account for 'other costs' THEN adds it to the loan value (i.e., interest oriented). If you read the endnote that is based on the fact that loans are for 115% of the value (payoff on old car?). How is that a legit 'cost' of the new hybrid car?
Second he is using the full cost of the hybrid. He is assuming that you dump a perfectly good car and buy a hybrid, NOT that you are bright enough to buy a hybrid when it is time to buy something. That is, he is assuming it is the full cost, not the incremental cost of the hybrid. While that MAY be a correct financial analysis, it is unlikely to be a real world analysis (IMO).
If I want a $22K hybrid and my other choice is a $18K car/SUV at 25MPG, then the 'additional capital expense' is $4K NOT $22K. $4K * 1.15 (assuming I use his magic math) is $4.6K incremental cost at 5.25% over 60 months that's about $88/mo in payment. Given the gas savings and higher trade in allowance, the case for a hybrid may be closer than he paints. Of course that assumes the competition for your car dollar is an SUV at 25 MPG if it is a small car at $15K and 30MPG then the hybrid case is less good.
The real issue is during a "I'm going to buy a new car, what will it be" purchase period. It is fair to deal with incremental costs and incremental improvements in gas mileage/trade-in value. As I read it, the article assumes a 'forced trade' at full cost, not incremental costs. I'm not sure that is a fair comparison.
But profits can't be judged by dollar amounts alone. What counts is the percentage of revenues those profits represent. "Our numbers are huge because the scale of our industry is huge," Exxon CEO Lee Raymond tried, probably in vain, to explain during last week's big Senate hearing on oil company profits. Exxon's profits last quarter amounted to 9.8 cents for every dollar of sales. Is that obscene? Well, it was more profitable than Shell (which netted 7.8 cents of each dollar of revenue) or Chevron (6.6 cents) or BP (4.6 cents). But compared to Coca-Cola (21.2 cents), Bank of America (28.3 cents), or Microsoft (33.2 cents), it was nothing to write home about.
Oil companies invest billions. getting a billion (or even 100 billion) isn't that much. The government, on the other hand has "made" $2.2 trillion on gas taxes. Thats money you and I could have spent elsewhere.
The government doesn't have enough to maintain roads? That's because the so called transportation money goes elsewhere - even money spent on transportation is more likely to go to new projects as that gets better visibility. Repairing roads isn't sexy and it doesn't get you votes.
Genius is one percent inspiration and 99 percent perspiration, which is why engineers sometimes smell really bad.
Wow... there are three responses to your post (four, if you count mine), and not a single one bothered to address your question. In fact, one of the posters (two, if you count me) decided to attack you instead.
Well, I'm not going to be left out. I think you hog the left lane, and you're an inconsiderate driver. You're a jerk, a complete kneebiter. Just shut up already with your "fact" and "figures" and "evidence", dickhead. We have no use for them on slashdot.
>I modded my TDI, but it's making 300 ft lbs of torque
258 for an unmodified Prius, *at zero RPM*. Low end torque is where electric motors shine.
>(when your foot is off of the throttle on a gas car, you've turned the motor into a vacuum pump - again, wasting energy).
When your foot is off the throttle on a hybrid the engine stops (unless it needs to charge the battery, run the air conditioner or keep the catalytic converter warm).
>anemic TDI (that is, one that only made as much power as your average hybrid)
Take another look. Only five years ago there was the three-cylinder Insight and the domestic-model Prius which had just enough power to be in a Tokyo traffic jam. Today's models are plenty adequate for freeway onramps and contingency maneuvers. The current Prius does 0-60 in about 10.5 seconds, which is not high performance but not anemic either.
The real way to make a good economic comparison is to compare buying a new hybrid vs. buying a new conventional-engine car, and do a time-value-of-money calculation to get present values of the cars and gasoline. Sure, monthly payments are what hits you in the wallet when you're making them, but they go away once you've paid off the loan, so you can calculate the Net Present Value of any interest you might pay to car dealers (might be positive or negative, depending on whether they're doing loss-leader loans to keep the car price higher.) Assume you're going to keep them both for the same number of years (otherwise it's way too messy; more on this later), estimate the effective interest rate for money over the next N years (which is not the same as the interest on your car loan...), estimate the future value of the car at the time you sell it (and calculate NPV), estimate the NPV of the price of any repairs you'll need to make, estimate the price of gasoline and amount you'll use over that period and NPV that.
So does it pay off, or not? Depends a lot on what kind of car you'd get instead, how long you'd keep the cars, and on the assumptions you make about the future cost of money, gasoline, and used cars. If you're spending the same amount of money on the car (overinflated price of a hybrid vs. buying a fancy car), it's probably a win. If you're comparing the hybrid to an econobox, it's probably not a win. If you think cars last 15 years, and you're comparing the hybrid to a used econobox now, another one five years from now, and another one in ten years, it's almost definitely a big lose, but you get fewer coolness points for driving around in beaters during the first ten years (after that, your hybrid will also be a beater, and repair costs are much harder to predict than for standard cars.)
I'm not the typical American car consumer - I buy cars with cash, generally new, don't drive very far most days, and keep them till they die of old age or are sufficiently close financially, so I spend less on cars and more on repairs (though replacing the engine in an old van did cost about the same as buying a used van of similar vintage, but since it had spent most of its years in California instead of New Jersey, the body was in really good shape.) A few years back, when my 1985 Toyota was getting old, we were thinking about keeping it running for a couple more years and getting an electric, but then the PT Cruiser came out, so we decided to go with the cool car instead... bought it on eBay.
Bill Stewart
New Fast-Compression-only CPR http://preview.tinyurl.com/dy575ks
Anecdotals, reported right here on slashdot, showed one very good use for hybrids. During the hurricane katrina immense long evacuation lines, MANY normal cars ran out of gas just sitting idling,creeping along, whereas the hybrids, shutting off completely at standstill, conserved their fuel and were able to make it out on the one and *only* tank of gas they could get at the time. I have no idea what sort of "price" you could put on such an advantage, but it's pretty high if it meant the difference between a successful evac for you and your family or stranded in a storm someplace because you ran out of fuel or starter battery charge.
And now with the aftermarket modding of hybrids into true plug-in hybrids, and some manufacturere making noises like they could offer them soon, the economics might be better, as one could conceivably keep the batts topped off from a solar array or wind charger at home, reducing reliance on both the grid and on fossil petroleum fuels.. now what the jerk government might do about road taxes then I have no idea, as this is such a variable and subject to non engineering related political change overnight. They would most likely switch to more monitoring and charge you by the mile traveled via some blackbox gizmo. That's one annoying part in all this, politics always gets involved. "here's a tax credit, go electric or hybrid!" "whoops, because our road fuel tax income just dropped, now we have to monitor you and charge by the mile and offer you an urban "congestion fee" alternative.
With all that said, I would like a pure electric vehicle, with the generator part that makes it a hybrid contained in a trailer for longer trips. Best of both worlds then, and no need to cram all the hybrid drive train stuff inside the vehicle..