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Comment by bkmrkr | Hacker News Reader

People are missing one factor.

In going from an 8 cylinder to a Prius you are going to save more gas than in going from a Prius to a Tesla, and even though we might not all be driving Teslas anytime soon the majority of us will drive more efficient cars.

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Old observation: "The difference between two headlights & one headlight is a whole lot less than the difference between one headlight & no headlights."

A hybrid may sip a fraction of the gas a V8 consumes, but a pure EV doesn't need any of the gasoline infrastructure at all. (My casual calculations indicate you can run an EV off home solar for half the price of the car.)

8-cylinders are maybe 5% or less in Europe. But there are many 1000cc engines instead. A Prius is "only" 15-20% more efficient than a similar non-hybrid, even less if you consider diesels (which pollute more even though they consume less fuel).

> diesels (which pollute more even though they consume less fuel).

Diesels pollute more (much more) the kind of air pollution (NOx) which makes bad air quality locally. But they pollute somewhat less greenhouse gas pollution, which is directly related to the amount of fuel burnt.

I heard that claim before, that Tesla's aren't a huge increase in efficiency over a Prius. It was based on the fact that they were powered by the grid and a mix of coal, gas, and hydro power in the US which generates carbon emisisons.

Assuming the future goes more green, which it getting looks that way, electric cars will get more efficient over time since the grid will change.

Your current Prius will always be the same level of efficiency though. A 40 mpg car won't magically become a 800 mpg one like an electric one will when it's powered by solar.

What do you mean by the same level of efficiency? I'm not sure if you're trying to shit on the Prius brand but every Prius generation have improved the MPG efficiency by ~10%.

It started at 40 mpg, then 44.5, then 50, and now the latest is 55.

You don't understand what I'm saying. A 40 mpg Prius will always be a 40 mpg Prius. It's tied to the pump. It has to burn gas.

A Tesla will get more efficient as the grid gets more efficient because it only uses electricity. That also means when it runs on solar it will be impossible to beat against gas cars. Make sense? This is why we shouldn't settle for hybrids.

You can now get a plug-in Prius. So, depending on how their mpg is calculated, cleaner electricity may have an effect. The batteries are still small, but the same argument that applies to short range EVs applies, most journeys are relatively short commutes, not long distance, and so plug in hybrids can spend a lot of time on electricity alone if they are topped up every time the reach home (and/or work).

Sidenote: it's better for the environment to buy a used Ford pickup truck than to buy a new Prius. The pickup will have been made in one factory while the Prius is made from parts from all around the world. It's already done a million miles by the time you buy it. Tesla not only has zero emissions, but they're also vertically integrated. For me, it's not all about which is the cheaper option to own. It's about what's going to help the environment the most.

Do you have a source on that? It doesn't seem right to me. Transportation is not the largest energy expense that goes into a product like a car; the largest energy expense is extracting and refining the raw materials into processed materials that are ready to be used for final production.

There's no way that the equivalent of one million driving miles' worth of pollution is emitted merely by moving around the pieces that then get turned into a car. Bulk surface/marine transport is extremely efficient.

> Transportation is not the largest energy expense that goes into a product like a car; the largest energy expense is extracting and refining the raw materials into processed materials that are ready to be used for final production.

Sure, maybe the GP's point is that (she thinks) (environmental impact of new Prius construction + n years of Prius driving > impact of n years of driving an existing pickup truck). I have no evidence for or against this, but I wouldn't be surprised if it's true for n=5 years and typical mileage/day. As you point out yourself, besides bringing the parts from all over the world, you need to mine the resources, spend the energy to cast them, etc.

That pickup part is not true(this is a myth invented by Top Gear). Most(over 80%) of the life cycle emissions of a car come from driving, not manufacturing. During its lifetime a Prius saves more than two metric tonnes of gasoline(comparing to another car of this size) - that's more that it weights.

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