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points by spaceywilly 1 day ago | 0 comments

Another way to view this is that driving a cybertruck every day is quite wasteful (no different than driving a full size gas pickup every day). One recharge cycle in a cybertruck uses enough energy to power a typical home for 8 days, 130kWh. If you aren’t doing truck things with it, it’s better to drive a more efficient EV or hybrid car. It uses almost twice as much Wh per mile compared to a model Y.

I think this is why these EV trucks don’t do well (ford also cancelled the F150 lightning). For truck things, they aren’t particularly capable (you’d get less than 100 miles towing). For daily driving duty, a car or small suv is much more efficient. You can power your home during a storm from most EVs these days, you’d just have to top it up more often

[–] dllu 1 day ago

Cybertruck uses like a fifth of the energy of a full size gas pickup truck and is only like 50% more than a typical smaller sized EV. The truth is that most homes don't use much energy apart from hvac. The Chevy Bolt can also power a home for several days if you only have the fridge and lights running.

[–] jmb99 1 day ago

> Cybertruck uses like a fifth of the energy of a full size gas pickup truck

Yes, but the energy density of the energy storage mechanism in the cybertruck is substantially lower than a gas pickup truck

[–] pseudosavant 1 day ago

Yes, but a gas engine is so inefficient that it loses more than half of that energy to waste heat. But almost all of the electricity is converted into useful power in an EV. A 600hp Cybertruck will go 13 miles on $1 of electricity, but a 400hp F-150 can only go 4.5 miles for $1 of gas. 50% more power at 1/3rd the fuel cost is a pretty significant benefit.

Not a Cybertruck fan myself, but unless you are going to tow or take many long road trips, an EV truck will work great for anyone who can charge at home. And most people don't tow, or take long road trips, with their trucks.

[–] margalabargala 1 day ago

> And most people don't tow, or take long road trips, with their trucks.

Except for everyone who owns an RV trailer.

[–] NetMageSCW 1 day ago

Which is roughly 7 million out of 49 million pickups, so a tiny number.

[–] margalabargala 1 day ago

One seventh of a category is not "tiny".

[–] seanclayton 17 hours ago

a loss of 7 million dollars in a 49 million dollar account is tiny, TIL

[–] thejazzman 1 day ago

And this matters why? It still fits in a garage and powered someone’s home for a week, while also being their vehicle. Stationary batteries couldn’t have driven themselves to the supercharger.

I am not a fan of the truck, but let’s make some sense here

[–] jmb99 1 day ago

No, but a stationary generator powered off a small volume of gasoline could have powered the house for the same amount of time, and then a gasoline powered car could've driven to the gas station to refill jerry cans. Both of which would cost substantially less than a cybertruck.

[–] porphyra 1 day ago

Yea but then you have to deal with gas which is nasty and stinky and noisy and polluting while having way less efficiency. A cybertruck charged with solar power is much more elegant and civilized.

[–] sportsracersss 1 day ago

Producing that enormous battery pack is nasty and stinky and noisy and polluting. It's just a cost that's paid upfront and the pollution is done in someone else's backyard.

[–] solyin 1 day ago

It's paid up front once. That battery is going to keep being a battery for the rest of its commercially viable lifespan. The gasoline just gets used up and you pollute over and over again to maintain having power.

[–] JuniperMesos 19 hours ago

Still a net pollution win. Pollution associated with industrial manufacturing of durable goods can be contained to specific areas and dealt with at scale by domain experts more easily than the diffuse pollution associated with burning fuel at point of use.

[–] mckn1ght 20 hours ago

Producing a gas powered car is just as stinky and nasty, so they cancel each other out. Once the EV is made, that can be the end of it.

[–] InvertedRhodium 1 day ago

Better theirs than mine or yours.

[–] jmb99 1 day ago

A generator to power your house costs <$1k. A car that runs on gas costs <$5k, or if you want something that "matches" a cybertruck, ~$50k new. You can buy a lot of gasoline for those things before you get close to what a cybertruck costs. I don't care how "elegant" solar panels and a cybertruck might be if you're throwing money away to achieve it. (Ignoring that you can't both drive your truck and have your house powered from it simultaneously, and I don't think anyone in history has considered the cybertruck to be "elegant" - at least no one with eyes.)

[–] bryanlarsen 1 day ago

Driving is wasteful. Cybertrucks and Prius's use similar amounts of energy per mile. Cybertruck is 0.4-0.5 kWh/mile, the Prius is 0.6-0.7 kWh/mile.

Of course the Prius Prime on electricity is way more efficient than both, but it still uses a lot more energy than a house.

[–] pintxo 1 day ago

European units (`Energy/100km`) work nicely here, lots of EVs are around `20 kWh/100km`, and most residential housing around here consumes less than `20kWh/day`, actually averaging `20kWh/day` would probably cover a well insulated house including heating (heatpump).

Yes, driving, compared to living, uses ridiculous amounts of energy.

[–] dllu 1 day ago

With dimensional analysis you can cancel it all the way out until it's just Newtons, which is actually just the average drag force times some efficiency multiplier.

[–] jaggederest 1 day ago

Dimensional analysis is a superpower honestly. Even in a software engineering career it's saved me from massive issues quite routinely

[–] vpmadd52huq 1 day ago

Mandatory XKCD: https://xkcd.com/3038/

[–] dllu 1 day ago

Also: https://xkcd.com/687/

[–] NetMageSCW 1 day ago

The HP 48G / 50G provides incredible unit handling. My main use for it these days.

[–] selimthegrim 1 day ago

Any war stories?

[–] jaggederest 1 day ago

Requests per second, bytes per request, bytes per second should all match up very closely under dimensional analysis or something is drastically wrong ;)

Little's law is another related phenomenon that is super critical. Measuring things when the units don't match has bitten me more than once.

[–] selimthegrim 1 day ago

Concur on Little's law

[–] gertlex 1 day ago

I'm curious if you can elaborate further? Would that make the comparison clearer, or is it just a side-note on your part?

[–] dllu 1 day ago

Work (energy) is force times distance. Since we're talking about energy divided by distance, it's actually just average force.

Actually newtons are just a constant factor (3.6) compared to Wh per km, since there are 3600 seconds in a hour while there are 1000 watts in a kilowatt. For example 144 Wh/km (or 14.4 kWh/100 km) would simply be 518 N. This also means that pushing along a Tesla on the highway at constant speed is roughly as hard as holding a 50 kg weight, giving you an intuitive sense of how "hard" it is to keep things moving.

Of course, in everyday life, since we buy electricity from our utilities in kWh rather than joules, it's more convenient to talk about kWh per km (or per mile).

[–] gertlex 1 day ago

Thanks. Was there a particular reason I'm not grasping for noting that on the comment you replied to? Seems like a comment that could be stated about any comment tackling about energy/distance.

Actually, I guess the comment you replied to was also not really clear in it's point, so I'll blame that guy for maybe diverging from the topic somewhat :)

(not trying to be negative, really! but my brain is a bit fuzzy from being sick, so thus feeling a bit dimwitted as I ponder comments)

[–] hamdingers 1 day ago

For comparison my cargo ebike, which is not particularly efficient, consumes about 30 Wh/mi (0.03kWh/mi) in medium assist while transporting an adult and two kids.

[–] SequoiaHope 1 day ago

My road bike consumes energy bars! And fruit!

[–] tga_d 1 day ago

Surprisingly enough, this makes acoustic bikes less carbon efficient per unit distance than electric ones, depending on the details of your diet. Of course, once the emissions are that low, this is more a curiosity than actionable insight (beyond the typical "less meat/dairy = lower emissions").

https://www.youtube.com/watch?v=HW5b8_KBtT8

[–] SequoiaHope 6 hours ago

Yaaa I’m vegan which helps a lot! A solar powered ebike is probably more resource efficient tho.

[–] sportsracersss 1 day ago

"Acoustic" bike? What is this madness?

I thought you were autocorrected badly but I guess this is a term people use?

[–] eclarkso 1 day ago

It's a joke referencing electric vs. acoustic guitars.

[–] s-zeng 1 day ago

What a coincidence, my cargo bike that regularly takes 50kg of cargo runs on the same stuff !

[–] DonHopkins 1 day ago

So you ride around town in a PacMan? Aren't ghosts a problem?

[–] RankingMember 1 day ago

Just gotta always have a Power Pellet in range

[–] RankingMember 1 day ago

I get 30 miles per sandwich! Beat that EV owners! :P

[–] solyin 1 day ago

What's in that sandwich though? The Cybertruck using California non-renewable energy creates 162g of CO2 per mile. A sandwich full of lamb generates 666g. A sandwich of lentils does 40g.

[–] barbazoo 1 day ago

Are those numbers right? 0.4 kWh/mile is 24.85 kWh/100km compared to about 14 kWh/100km my Kia Niro EV uses.

[–] bryanlarsen 1 day ago

Those numbers are saying that:

- the Cybertruck uses almost twice as much energy as your Niro EV

- the 40% efficient Prius uses about 2.5x as much energy as your 95% efficient Niro EV.

what seems off?

[–] benatkin 1 day ago

Driving uses a lot of energy. It's wasteful if you aren't getting a good use out of it (of which just driving around to relax could me considered a good use, but of which some manager requiring RTO might not be).

[–] pembrook 22 hours ago

Driving is not wasteful. Energy is not a scarce thing in the universe.

Using energy is not bad. Creating excess carbon emissions is bad.

We need to be able to hold two ideas in our heads instead of blindly repeating trendy religious dogma.

[–] jotux 1 day ago

>For daily driving duty, a car or small suv is much more efficient.

I have a lightning and it averages 0.5kwh/mile and my electricity price is $0.15/kwh, so it costs me $0.075/mile to drive. At current gas prices that's pretty much the same as a very efficient hybrid compact car (55mpg @ ~$4/gallon). If I had solar I could probably offset almost all of the lightning fuel cost based on where I live (sunny) but it's so cheap it's not worth it.

Do you mean "much more efficient" in places where electricity rates are significantly higher than the national average? Or only much more efficient when compared to when you're charging at charging stations?

[–] spaceywilly 1 day ago

I mean efficient in engineering terms, not economics. A cybertruck is not as efficient as a small SUV (model Y) which is not as efficient as a sedan (model 3).

Cybertruck — 2mi/kwh

Model Y — 3.8mi/kwh

Model 3 — 4mi/kwh

[–] NetMageSCW 1 day ago

But economic terms are what matters.

[–] huijzer 1 day ago

> Another way to view this is that driving a cybertruck every day is quite wasteful (no different than driving a full size gas pickup every day). One recharge cycle in a cybertruck uses enough energy to power a typical home for 8 days, 130kWh.

Driving in general uses a lot of energy. It’s the physically moving a 1,000 kg or more object that takes a lot of energy. Orders of magnitude more than a few lights or a phone. Same with flying of course; also moving a heavy object.

[–] sanj 1 day ago

As someone towing every weekend with a Lightning, I get closer to 150mi.

ICE trucks are equally inefficient for towing. People just don't seem to be able to factor it in.

[–] porphyra 1 day ago

The thing is that ICE vehicles are so inefficient to begin with, but a towed trailer needs the same amount of energy regardless of what is towing it.

Imagine a trailer takes 1 unit of energy to move, and ICE truck takes 5 units to move itself, and EV truck takes 1 unit to move itself.

The ICE truck towing it would go from 5 units to 6 units, reducing the range by 16%.

The EV truck would now go from 1 unit to 2 units, reducing the range by 50%.

So the better your efficiency, the worse you are at towing. Ideally EV trucks would have such a huge battery that even when the range is reduced by 50%, it is still as long as a gas truck's range, but modern battery technology is still too sucky to achieve this.

[–] jmb99 1 day ago

Are they really that inefficient? My 94 Roadmaster sedan gets 14ish mpg towing 7000lbs at 60mph, which works out to a bit over 300 miles on a tank. I figured your average gas truck would do at least that well, and they have larger tanks.

[–] dmtroyer 1 day ago

meanwhile, my impression is the whole poor towing narrative (while true) is a big part of what killed the ev truck when how many people use trucks in the way they could otherwise use a four-door sedan.

[–] lightedman 1 day ago

"ICE trucks are equally inefficient for towing."

Not so sure about that one, boss. I can fully-load up a Ford Ranger to its 7500lb rated towing capacity and lose ~10% in fuel economy/range while you just dropped something like 30% (from the base power package range of ~240 miles, platinum package at 300 miles you're losing half if you only get 150 miles out.)

[–] scottyah 1 day ago

You're talking about the difference between towing and not towing per vehicle, not the difference in energy used towing between vehicles.

To get their equal ranges, a Ford Raptor would have a ~4 gallon tank. The fact that the cybertruck can go so far while not towing is the miracle. How far do you think you're going to get with 4 gallons?

[–] devin 1 day ago

If the underlying energy is coming from a renewable source, then it wouldn't matter all that much, would it?

[–] mhluongo 1 day ago

Power still costs money.

[–] tarpitt 1 day ago

Sure but even electrical power from natural gas or nuke plants is way cheaper than gasoline. Power plants employ massive economies of scale in generation. Even the cost of solar power has fallen dramaticially.

I think in general, a country trying to become industrious and eco-friendly by saving energy is like a person trying to become a millionaire by pinching pennies. Once you have optimized an economic system to eliminate the major cost centers, you're going to have extremely hard time improving it through further cost savings.

For example, If my expenditure roughly matches my income, I would need to eliminate 100% of my expenses just to make enough surplus to match doubling my income. Once I have managed the major cost centers (rent, insurance, etc.) it's not going to be worth my time to further optimize my expendature, the time would be better spent improving my income

For EVs, the fuel cost is already low. The next cost centers are like maintainance, tires, battery life. It would be better to attack these other cost centers or somehow pursue functionality that increases utility of the car.

[–] duderific 1 day ago

Just FYI, in some areas of California, served by PG&E, electricity at peak times is $.58/kwh. When gas was around $4.00/gal, it was actually cheaper to use gas in that scenario. (I have a PHEV so I can do either.)

You can get a special account for home charging that lowers that rate to $.32/kwh, and at my work I can charge my car for $.28/kwh. At those rates, and with gas where it is now (typically $5.50 - $6.00/gal) it makes sense to use electric.

[–] tarpitt 1 day ago

Yes it's ridicuous. Many of the charging stations here in PA charge 40c/kwh (my break-even is 30c/kwh). It's not profitable against gas even at these prices. Luckily residential rates are 13c/kwh but it's very inconvenient out here still.

[–] NetMageSCW 1 day ago

Is that using today’s gas prices?

[–] tarpitt 1 day ago

Yeah I did the math for like 3-4$/gallon, and the efficiency of my car.

It's just ridiculous, there are no charging stations around here and it's like 50/50 chance they charge you some outragous price and have an annoying app or it's completely free to use.

[–] tarpitt 1 day ago

I own a pretty typical phev sedan (Gen 2. Volt), and I use more electricity on my 20 mile commute than the rest of my power usage combined.

All cars just use a ton of power moving a lot of mass. It is actually impressive, it's like 100KW at full tilt. I think i saw someone do the math for how much power transfer you would need to get EV charging as fast as gasoline refuelling: It's in the megawatts.

The only way you could signifigantly reduce power usage of vehicles is to reduce mass dramaticially with a motorcyle or autocycle. The Aptera is an interesting autocycle design based on this line of reasoning, but we are also seeing the emergence of a lot of electric motorcycles.

[–] spaceywilly 1 day ago

Yep, having each individual person commuting in their own car is just not that efficient in general. Another data point that amazes me is the NYC subway uses 4-5 million kWh per day. Sounds like a lot until you realize that around 4 million people ride it every day, that’s about 1kWh, or maybe like 20 cents of electricity, per rider. A person commuting 35 miles in an EV would take about 10 kWh daily. They’re never going to beat the efficiency of public transportation.

Also regarding filling up an EV as fast as gasoline, there’s a company in China that has demonstrated charging from 20-80% in 5 minutes. They’re using 3MW charging.

It makes you realize why gasoline has been so popular for so long, you can stop for 5 minutes and dump 500 kWh of energy into your tank. Unfortunately most of that is wasted as heat during the combustion process.

[–] scottyah 1 day ago

The subway has some great efficiency gains because it's use is so narrow. It can only transport humans and small amounts of luggage, and only goes from point to point with no variability or any real use for transporting any of the materials those people need to survive. You're just dumping the costs off to other areas.

Also, if you factor in the construction, idk what the timeline to pay that off would be.

[–] eldaisfish 1 day ago

ok, so then you should also factor in the environmental destruction cause by building roads, the cost of the roads, the environmental cost of burning petrol, the environmental damage of extracting and refining petroleum, and so on.

[–] NetMageSCW 1 day ago

I thought the comparison was to a BEV, not ICE.

[–] tarpitt 1 day ago

>Also regarding filling up an EV as fast as gasoline, there’s a company in China that has demonstrated charging from 20-80% in 5 minutes. They’re using 3MW charging.

Yeah that's the exact post I saw. I didn't believe the video at the time but I suppose it's possible with enough battery paralellism and cooling.

https://www.thecooldown.com/green-tech/new-ev-technology-cha...

[–] sourweasel 1 day ago

In addition to the Aptera, I think there's a potential market for the enclosed 2-wheel vehicles also like the MonoRacer. The aerodynamic efficiency gains of enclosed cabin motorcycles is huge and greatly improves range, especially at highway speeds. I'd like to see something similar at a lower price range and produced in greater volume.

https://www.peravescz.com/electric-version/

[–] nightbun 1 day ago

In summer time with a pool and AC, we use 100kw in one day

[–] ToucanLoucan 1 day ago

Yeah the Silverado EV has my attention but it's the same issue: if you, like me, actually use your truck for truck shit, an electric truck is a substantial, notable downgrade from ICE.

That said if you have a Mall Crawler who's heaviest loads are your monthly Costco run, an electric truck would probably be great for you. I still wouldn't recommend a Cybertruck though.

[–] tiohijazi 1 day ago

Yeah, wasteful, like one day we will ever run out of energy lol