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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."
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.
Lead acid batteries, which I think are what are used in most hybrids, are the most recycled commodity in the country.
I think that hybrids generally use NiMH, not lead-acid batteries. For instance, the Toyota Prius. But I think that NiMH batteries are just as recyclable.
www.timcoleman.com is a total waste of your time. Never go there.
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.
What would it be like to manage the disposal of these batteries if there was suddenly tens of millions of such cars driving around?
Current hybrids use Ni-MH batteries, which aren't particularly toxic from a disposal perspective, and, more importantly, conatin valuable metals that can be recovered through recycling.
Toyota, for example, pays a $200 "bounty" for dead batteries, because the nickel in them is quite valuable.
Ni-MH is probably the most "eco-friendly" battery technology. It's certainly worlds better than Ni-Cd.
[i]No production diesel can currently meet California emission standards in the US.[/i]
Not true. The current diesel fuel standards in the US prevent the cleaner diesel engines from being sold. The engines exist and are being sold everyday in Europe. It's our dirty diesel fuel that is holding them back. Thankfully our diesel standards are set to go up in the next year or two which will open our markets to these very efficient and clean diesels.
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.
And that somehow nullifies the comparison? Why?
And, your data is completely wrong. Diesel contains 139,000 BTU/gallon. Gasoline contains 124,000 BTU/gallon. (both figures rounded to nearest 1000) That's about 10%, not 30%.
However, the diesel combustion cycle is MUCH more efficient than most gasoline (Otto) combustion cycles. The Atkinson and Miller cycles can increase gasoline combustion efficiencies, but usually in a narrower operating region. THAT's where the difference comes in.
NOx emissions are particularly problematic with diesel engines. The higher compression ratios create considerably more work for the catalytic converter.
And continuing studies show that NOx emissions are not the "root cause" of air pollution that scientists once thought they were. "Cats" on diesel engines are near worthless, and NOx is almost completely handled by combustion technology. Run a modern diesel on 100% biodiesel, and even the emissions argument goes out the window. Your "net" CO2 emissions are drastically reduced (they would go to ZERO if the biodiesel production uses methanol derived from an organic source instead of natural gas.) Someone also addressed the cost "premium" of buying a diesel vehicle. The cost for the diesel upgrade on the new Passat is $255 (you read that right, two-hundred fifty-five 'murican dollars), and the reward is roughly 35% better fuel economy, and the ability to run on a renewable, sustainable fuel. How much over MSRP are people paying for Prii again?