Prius saves gas money? (follow-up) | Hacker News Reader

Prius saves gas money? (follow-up)

aaronhawley.livejournal.com

7 pointsvgnet14 comments

"A convenient and fair comparison is the Corolla also made by Toyota."

No a fair comparison would be a non-hybrid Prius. I don't know if Toyota makes such a vehicle, but Honda makes the Civic in both a hybrid and conventional model, so a direct comparison would be fair. I'd actually like to see that analysis as I drive a Civic.

To borrow from Joel Spolsky, what this shows you is that you can prove anything with a contrived example. More specifically, for any comparison that isn't night-and-day, you can almost always find a reasonable set of assumptions that leads to your preferred conclusion.

> I don't know if Toyota makes such a vehicle

They don't, and actually the Prius sits between the Corolla and the Camry in size and features. The cost premium over a Camry is only about $2k, and the fuel economy improvement is more dramatic. (The Camry has substantially more power, but the Prius's flat torque curve probably reduces the real-world difference).

Another problem with this analysis is that on the one hand it ignores resale value, but on the other hand assumes that the owner won't keep the car more than a few years. Maybe Priuses have crap resale value, but the author doesn't state that much less back it up.

But the biggest problem is that only businesses buy cars this way.

People don't buy sports cars because they get them to work faster, and people don't generally buy SUVs because they have to drive off-road to get to the grocery store. People buy cars (or forego them) to tell themselves a story about what kind of person they are (and there are many comical instances where it tells an entirely different story to others).

Business do buy cars this way, and if you look at those that do a lot of city driving in an area with even moderately high gas prices (say, Vancouver, with gas at US$5.15 a US gallon), you'll find that, for instance, 90% of the taxis are Priuses.

> (say, Vancouver, with gas at US$5.15 a US gallon), you'll find that, for instance, 90% of the taxis are Priuses.

That appears to be an exaggeration, according to this http://www.calgaryjournalonline.ca/news/34-news/1281-calgary... as of mid-2010, 50% of the fleet was hybrid. I suppose it's possible, but unlikely they ramped up that quick to over 90% hybrid (I imagine there would be some Fusions in the mix like in SF and Boston).

The same comparison can be done (for estimating savings) between diesel and unleaded gas in France. I did a similar calculation years ago and you had to drive your diesel vehicle more than 10 years before making any savings. Basically the initial investment trumps the ongoing costs.

The price of fuel looms large in people's minds, since it is so visible, but if you actually keep track, it just doesn't add up to much compared to the cost of the average new car. Just goes to show, measure before you optimize :)

Yeah. it's all about perception. Since you refuel often, you see the fuel cost much more often than the actual initial car costs. It's constantly in a "top of mind" position for consumers. You can find the same phenomena across different fields. Like when you hear about people dying from cancer the whole time on TV, you may feel there is a great risk to actually get it anytime, while in fact, the main key factor to develop cancer is simply "age" (there are, of course, young folks diagnosed with cancer, but it's a clear minority).

Like the article says, saving money isn't the only reason to drive a hybrid.

If you care about the environment, and are wealthy enough, you might be willing to pay a premium to reduce your carbon footprint.

Like the article says, however, footprint is also a factor of the car's manufacturing process. If that piece of information is not being disclosed, you have no idea whether you are, overall, reducing the carbon footprint. Making a car takes huge amounts of energy (and therefore, "carbon"). The best thing you could do as a car owner is to keep your car as long as possible. It's not what the industry wants, however...

Like the article also says, you don't actually know if you're reducing your "carbon footprint" or not.

You don't know how much more carbon is produced in the manufacture of a prius than the manufacture of a non-hybrid.

Price is generally a pretty good indication of resource intensity if you're comparing two things with generally similar level of externalities and subsidies/taxes.

If anything I would say the fuel cost understates the externalities, at least in the US.

not only that, but if you believe in economics, you are "voting with your dollar" for alternative technologies, signaling to auto manufacturers that a growing number of people care about cars with increased fuel economy and reduced emissions.

Yeah, but don't forget that emissions = emissions generated to produce the car (A) + ongoing emissions when using the car (B).

Since Toyota does not disclose the (A) part, just considering the (B) factor is pretty much pointless. (A) is supposed to be huge to begin with, and there's no way you can make up for the initial emissions produced to make the car in just a few years of driving.

Hybrid cars Manufacturers are not stupid. They don't want you to look at the (A).

This argument only works when comparing a Prius to a Corolla... Which is the entry level bottom tier sedan from Toyota. I think it would be a bit more fair to use the Camry as the alternative car.

I'm a Prius owner and I didn't decide to spend an extra $6k just to get a Prius for the gas savings, otherwise I'd have a Camry. If I didn't buy a Prius I would have bought a similarly priced car because... that was the price range I was shopping in.

it would be interesting to add resale value to this calculation.

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