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Comment by cataflam | Hacker News Reader

> The total energy usage shouldn't be much of an issue as we'll move electricity use from refineries to charging batteries – I believe these are at least in the same ballpark.

I wouldn't be so sure. Back of the napkin estimate: for every 2M electric cars, you need 1 more nuclear power plant.

  - approx. 18 kWh per 100 km for a Tesla
  - let's say 15000 km per year (close to the average in France for example)
  - total consumption over a year for 1M cars is roughly 2.5 TWh
  - total production of a nuclear power plant varies, but is roughly 5-7 TWh per year on average

That's a lot of extra power if you want to replace all the cars. For example in France, that'd be the equivalent of 20 extra nuclear power plants, or the equivalent in nuclear + solar + wind + coal/gas/...

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Interesting calculation! But the point of shifting electricity usage from refineries to car batteries still stands: Apparently it's 1.5 kwh per liter of gasoline [Edit: this might not be accurate, or might be mainly related to drilling, see comments below]. At 7-8 liters/100km we've already covered 11 kwh.

Edit: And 7-8 liters/100km for a Tesla seems optimistically low. But maybe 18kwh is also optimistic.

I think you should cite a source for that 1.5 kWh/litre number. It seems there are a lot of varying claims here [0].

Looking at the US statistics for 2019, it seems refineries used 47 140 million kWh of electricity [1], and produced 3 199 032 thousand barrels of Finished Motor Gasoline [2], plus a lot of other products. That makes 0.093 kWh per litre, for the package of a litre of gasoline plus a bundle of other products. If gasoline is half of the output of refineries, then the rate is more like 0.05 kWh per litre.

This is just for refining, and doesn't include the energy cost of drilling, transport, etc. But 0.05 is a long way from 1.5.

[0] https://greentransportation.info/energy-transportation/gasol...

[1] https://www.eia.gov/dnav/pet/pet_pnp_capfuel_dcu_nus_a.htm

[2] https://www.eia.gov/dnav/pet/pet_pnp_refp_dc_nus_mbbl_a.htm

Yes you are correct, that's an important thing to look at. Apparently the main energy usage which causes the 1.5kwh number is drilling, I'll see whether I can find some sources.

If it's actually drilling that makes a big difference because drilling might not be done where the oil is raffined

I can't edit my own post anymore, but I've looked into it more. Total average production should not be an issue, at least in Europe. However peak power could be and will require some care.

See https://news.ycombinator.com/item?id=27361065

Sweet. Maybe we invest in travelling wave reactors or electromagnetic rod / saltwater harness designs.

Or we just start building more nuclear infrastructure on less safe designs (although not sure why we should do that when we have safer designs available), given that the consequences of not pushing nuclear immediately vastly outweighs the consequences of pretending it's less safe than the status quo.

Or we don't change all thermal cars with electric cars. It's time we realize that moving a 1+ ton vehicle for 80kg of people on average is a folly. We need alternative ways of transportation, more efficient, less polluting

In France that's a fact of life and significant improvements are underway. Public transit is very good in most bigger cities, bike lanes are plentiful, high speed rail is available for most intercity travel, and all of those are actively being improved.

So the math is for an already decently non-car centric country.

As someone who doesn't want to own a car I am biased, but to me there are still a few usecases where a car still makes sense:

- If you don't live in a big city, public transportation is far from enough

- When you want to go on vacation you not only want to travel from A to B, you also want to be able to transport all your stuff and not be bound by infrequent scheduling, and you want some kind of mobility freedom at your destination

- For your bi-weekly grocery shopping you need to be able to haul a few dozens of kg of stuff that takes something like half a m^3

For all of those, there's no easy alternative, and I understand why people used to this way of life don't really want to change. Bikes can replace some of it, electric bikes even more, and why not electric cargo bikes. But it's still very expensive, especially when you can't totally replace your car. I think the intermediate solution will be some carsharing solution, where 1 car is not owned by 1 person or 1 family but shared on average with a few families, accross a whole city.

Public Transport outside of big cities: a problem that shows that we have to look far beyond the question electric vs ICE cars. Back when nobody owned a car, even small villages had their own schools, shops, government offices. When everybody got a car, those were considered ineffective and consolidated in bigger cities. The long term solution is a return to decentralized structures.

Vacation: hobbies that require hauling a lot of gear to remote areas only became feasible with a car and might become a thing of the past, like hunting from horseback. Maybe you can rent a SUV only for those time you need it instead of using it for bringing kids to school.

Bi-weekly shopping: before corona, I walked to the nearby shops every 3 days or so. To limit exposure to mask-less shoppers I am now using a hand cart for bi weekly shopping. If you live farther away from shops, a cargo bike might be an alternative.

You're touching on the hidden part of the iceberg indeed: transportation doesn't exist in a vacuum, it's both a cause and a consequence of the organization of our cities, our shops, our jobs, and all of those: since we'll need to reduce the quantity of energy we use, we'll also need to redefine how our cities are organized

That's only possible if you change zoning and people are against changes in zoning to increase affordability. They won't change their mind for something "optional" like walkability.

They are building their very own doom.

Public transit is for dense cities. Works brilliantly on Manhattan; can't be made reasonable in Houston.

Western Europe is densely populated and has passenger railways since 19th century. Bus service (of sorts) started in Paris in mid-17th century.

That isn't true. Houston has okay transit, and could have much better with some small investment. It won't be ask brilliant as Manhattan, but it can be a lot better. And Houston unlike most cities will allow you to build transit friendly (though they do need to get rid of their excessive parking requirement to really make transit useful)

Talk is cheap. Most people talking though don't actually believe that as we can tell by their actions: they support politicians who don't do anything about the bad state of alternative means of transportation. In fact many of the politicians they support are doing more harm to alternative transport than those politicians who honestly believe alternative transport is a bad idea and oppose it.

This too. What you're suggesting requires completely changing our way of life from how we gather food to how we design housing and communities.

I'm not saying you're wrong, it's just going to be nearly impossible to convince people when lunking masses of steal around for no good reason is such a large part of their life.

Those numbers are why I’ve always thought cleaner fuel options were the real future here (like natural gas and hydrogen).

Natural gas is significantly dirtier than nuclear, and hydrogen (in terms of how we use it) is a component of an energy storage technology and not a fuel source.

But significantly cleaner than oil and abundant enough to make an impact much sooner.

Impact in what? It still releases carbon dioxide into the atmosphere.

Way less carbon dioxide per joule produced, also, no sulfuric dioxide.

Reducing and replacing gasoline/diesel usage.

LNG powered cars have been available for a long time. They never caught on (speaking from a Swiss perspective). Whatever the reasons may be: Less dynamic driving experience, not enough LNG gas stations, expensive to retrofit, no cool new cars, no that much cheaper compared to gasoline - the consumer apparently just doesn't want them.

Natural gas isn't much better than gasoline, biogas is a good option but the production capacity is limited at best.

Hydrogen won't be viable for consumer vehicles unless we get a Hydrogen Elon Musk who optimises the production efficiency by 500%. (It takes around 55kW of electricity to produce the hydrogen needed to get 11kW of energy from a fuel cell vehicle).

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