5 ms·

>you're lumping all hybrid drivetrains in together and assuming they're all equally reliable and equally have the same TCO math I’m not though, you’re just mak

by bumby 1y ago

>you're lumping all hybrid drivetrains in together and assuming they're all equally reliable and equally have the same TCO math I’m not though, you’re just making that assumption. For example, as “comparable manufacturers” if I select Toyota (because it has a reputation for reliability) I can compare the Prius to the Corolla (because they’re both at a similar price point in their respective categories). This “should” favor the Prius because the Corolla has a CVT (which is known to be less reliable) but TCO comes out about 8% lower for the Corolla. I’m not lumping all together, I’m deliberately trying to make reasonable comparisons. Now I could also pick and choose to go the other way with a similar comparison. The end result seems to be that there is a distribution of differences that are reasonably close, but with enough variance to say it looks like a wash in TCO. Point being, strong conclusions may not be warranted. >Which is why I made a big point of mentioning my usage of "series", which flew right over your head. It did not go over my head. In fact, I brought it up in the very first post before you responded. [1] I even reminded you of that [2]. This is why I’m saying it seems like you are reflexively responding without actually reading for comprehension or clarity. [1] https://news.ycombinator.com/item?id=44422207 https://news.ycombinator.com/item?id=44422207 [2] https://news.ycombinator.com/item?id=44424531 https://news.ycombinator.com/item?id=44424531

Retric 1y ago
> compare the Prius to the Corolla That’s not a direct comparison. Toyota sells hybrid and non hybrid corolla’s and the hybrids are cheaper to own @ 5 years here. https://www.edmunds.com/toyota/corolla/2024/cost-to-own/ https://www.edmunds.com/toyota/corolla/2024/cost-to-own/ https://www.edmunds.com/toyota/corolla-hybrid/2024/cost-to-own/ https://www.edmunds.com/toyota/corolla-hybrid/2024/cost-to-o...
- bumby 1y ago
  That’s fair. But looking at the numbers for my locale, the effect size is extremely small: about 0.6% cheaper. So, to piggyback on the points made earlier, if we have high variance and small effect size, we probably shouldn’t be making any strong claims. The more appropriate conclusion is that there is no difference, or not strong enough data to make a claim one way or the other.
  - Retric 1y ago
    It’s not that small of an effect size relative to the upfront price difference. Subtraction of the initial cost of the non hybrid from both numbers is very reasonable because you know what that is for both. Also, the payback for a more expensive upfront car at year 5 on a car likely to last ~26 years doesn’t mean they are also equal for the next 21 years.
    - bumby 1y ago
      Maybe I’m misunderstanding your point, but TCO factors in the upfront cost, including financing assumptions. I can’t think of a good reason why you’d want to disregard upfront cost when calculating TCO; it’s probably the #1 determining factor for most people buying a car. (And not to belabor the point, but the original claim was about TCO). I’m not sure I would use the 25+ life because that doesn’t reflect how long a person will keep it. The depreciation captured by the TCO is a better representation of that effect.
      - Retric 1y ago
        I’m not discarding all costs, I’m looking at the difference in upfront costs. Suppose I’m paying cash and it’s an extra 2,000$ by my TCO drops by 0.1% over 5 years is that a worthwhile investment? Without knowing what the car costs you can’t tell. What matters is the difference in cost vs the difference in TCO. You’re buying a car either way.
        bumby 1y ago
        I don’t think that’s an unreasonable take, but it does move us away from the generalization that hybrid TCO is lower. It’s like instead saying “Hybrid TCO will be lower if you pay in cash and live in a high fuel cost area.” That’s a more nuanced take by adjusting the assumptions. Sometimes adjusting them is warranted, and sometimes it’s just to game the outcome you wanted.
        Retric 1y ago
vel0city 1y ago
> It did not go over my head. > Ah, ok. I didn’t realize “series” is a specific term of art in the EV space. You acknowledged you did not originally understand what "series" meant when I was talking about a "series hybrid". And your "reminding me" is you continuing to show you were not aware of what my usage of the word "series" meant in terms of hybrid drivetrains and instead "using it in the pure reliability domain sense". And your first comment points out you didn't get the idea that a series hybrid doesn't have a lot of the same ICE components, instead it seems you had a parallel hybrid design in mind. > but TCO comes out about 8% lower for the Corolla In what timeframe comparison, 5-year? How many miles? Which gas markets, is gas $3/gal or $5? What does a 10-year comparison look like? Are you including residual value on the cars after that 5-year period to see a total cost after depreciation? What does a used comparison look like? And yes, why not compare the Corolla ICE vs Corolla Hybrid, wouldn't that be a more apt comparison? One is a sedan and one is a hatch, they're different cars with different branding presence. Looking at the numbers, drawing that out from a 5-year comparison to a 10-year comparison (or more) would probably tilt the math towards the Prius being cheaper in the end, and I'd imagine even more so at a 15-year point. But we don't actually have these numbers, and these are projections of what these cars might have in terms of TCO, not any detailed study of actual TCO.
- bumby 1y ago
  I was being polite to the other poster so I can address the more germane claim in their reply without getting derailed by explaining why the less important point was irrelevant. The fact is the series “term of art” in the reliability domain and the hybrid engineering terminology mean the same thing. They are derived from the same concept. The numbers come from the Edmunds site. Eg fuel cost by locality, 15k miles a year etc. You can look at the site for all their assumptions, but some of it is proprietary. >But we don’t actually have these [TCO] numbers Exactly! So why are you making strong conclusions in the absence of data?! This is why it comes across as if you are an ideological argument instead of a data-literate one. “I don’t have any data, but it just makes sense to me” is not the type of curious discussion I was after.
  - deleted 1y ago
    [deleted]

by bumby 1y ago

Retric 1y ago

> compare the Prius to the Corolla That’s not a direct comparison. Toyota sells hybrid and non hybrid corolla’s and the hybrids are cheaper to own @ 5 years here. https://www.edmunds.com/toyota/corolla/2024/cost-to-own/ https://www.edmunds.com/toyota/corolla/2024/cost-to-own/ https://www.edmunds.com/toyota/corolla-hybrid/2024/cost-to-own/ https://www.edmunds.com/toyota/corolla-hybrid/2024/cost-to-o...

bumby 1y ago
That’s fair. But looking at the numbers for my locale, the effect size is extremely small: about 0.6% cheaper. So, to piggyback on the points made earlier, if we have high variance and small effect size, we probably shouldn’t be making any strong claims. The more appropriate conclusion is that there is no difference, or not strong enough data to make a claim one way or the other.
- Retric 1y ago
  It’s not that small of an effect size relative to the upfront price difference. Subtraction of the initial cost of the non hybrid from both numbers is very reasonable because you know what that is for both. Also, the payback for a more expensive upfront car at year 5 on a car likely to last ~26 years doesn’t mean they are also equal for the next 21 years.
  - bumby 1y ago
    Maybe I’m misunderstanding your point, but TCO factors in the upfront cost, including financing assumptions. I can’t think of a good reason why you’d want to disregard upfront cost when calculating TCO; it’s probably the #1 determining factor for most people buying a car. (And not to belabor the point, but the original claim was about TCO). I’m not sure I would use the 25+ life because that doesn’t reflect how long a person will keep it. The depreciation captured by the TCO is a better representation of that effect.
    - Retric 1y ago
      I’m not discarding all costs, I’m looking at the difference in upfront costs. Suppose I’m paying cash and it’s an extra 2,000$ by my TCO drops by 0.1% over 5 years is that a worthwhile investment? Without knowing what the car costs you can’t tell. What matters is the difference in cost vs the difference in TCO. You’re buying a car either way.
      - bumby 1y ago
        I don’t think that’s an unreasonable take, but it does move us away from the generalization that hybrid TCO is lower. It’s like instead saying “Hybrid TCO will be lower if you pay in cash and live in a high fuel cost area.” That’s a more nuanced take by adjusting the assumptions. Sometimes adjusting them is warranted, and sometimes it’s just to game the outcome you wanted.
        Retric 1y ago

vel0city 1y ago

> It did not go over my head. > Ah, ok. I didn’t realize “series” is a specific term of art in the EV space. You acknowledged you did not originally understand what "series" meant when I was talking about a "series hybrid". And your "reminding me" is you continuing to show you were not aware of what my usage of the word "series" meant in terms of hybrid drivetrains and instead "using it in the pure reliability domain sense". And your first comment points out you didn't get the idea that a series hybrid doesn't have a lot of the same ICE components, instead it seems you had a parallel hybrid design in mind. > but TCO comes out about 8% lower for the Corolla In what timeframe comparison, 5-year? How many miles? Which gas markets, is gas $3/gal or $5? What does a 10-year comparison look like? Are you including residual value on the cars after that 5-year period to see a total cost after depreciation? What does a used comparison look like? And yes, why not compare the Corolla ICE vs Corolla Hybrid, wouldn't that be a more apt comparison? One is a sedan and one is a hatch, they're different cars with different branding presence. Looking at the numbers, drawing that out from a 5-year comparison to a 10-year comparison (or more) would probably tilt the math towards the Prius being cheaper in the end, and I'd imagine even more so at a 15-year point. But we don't actually have these numbers, and these are projections of what these cars might have in terms of TCO, not any detailed study of actual TCO.

bumby 1y ago
I was being polite to the other poster so I can address the more germane claim in their reply without getting derailed by explaining why the less important point was irrelevant. The fact is the series “term of art” in the reliability domain and the hybrid engineering terminology mean the same thing. They are derived from the same concept. The numbers come from the Edmunds site. Eg fuel cost by locality, 15k miles a year etc. You can look at the site for all their assumptions, but some of it is proprietary. >But we don’t actually have these [TCO] numbers Exactly! So why are you making strong conclusions in the absence of data?! This is why it comes across as if you are an ideological argument instead of a data-literate one. “I don’t have any data, but it just makes sense to me” is not the type of curious discussion I was after.
- deleted 1y ago
  [deleted]