[abelsson]

For reference, gas contains about 33kWh of energy per gallon, and if we assume you pump 20 gallons in 5 minutes when you fill up your car you have an effective energy transfer rate of about 8 MW at your gas pump. Even if we give an electric vehicle a 3x efficiency ratio, we still need about 2.5 MW to be equivalent to the old petroleum infrastructure.

[hwillis]

More like 36 kWh. Average mpg of new cars is 25.5 mpg (.71 mi/kWh) while Teslas get 3.2-3.8 mi/kWh so the efficiency ratio is closer to 5x. With 4 gallons/minute, that's 7.2 kWh per gallon/1.73 MW. In the US pumps reach up to 10 gallons/minute so 4.3 MW and 17.3 MW for truck-filling pumps. Not all pumps hit 10 gallons/minute though.

2 or 3 MW would charging power would require a really specialized battery and will probably never be worth it. The real advantage of an electric car is letting it charge overnight and adding some extra time over long journeys isn't a big inconvenience- its less time than unexpected traffic would take up. Plus the time is overall made up for by never having to fill up if you come home to charge overnight once a week. Same thing applies to trucks. An hour-long fill up once a week gets replaced by nightly charging.

[saurik]

> Average mpg of new cars is 25.5 mpg (.71 mi/kWh)...

This is not a reasonable way of doing this math because it loads the numbers with "people who want a large and heavy car can't or wouldn't buy an electric, pulling down the average miles per gallon for gasoline powered vehicles"; to do this comparison fairly requires looking at the energy conversion efficiency of the engine, tank/battery, and transmission in isolation of the rest of the car body. Another way to put this: if you manage to buy an electric Hummer, you are going to be spending an insane amount of time charging it, because it would use as much more electricity as it uses more gas ;P. If you really need to estimate this using miles per gallon, you need to look at a gasoline-powered car which looks like a Tesla (being about the same size and contour), not the average new car purchased by a consumer. (FWIW, a quick eyeball of this is looking like 40 mpg.)

[hwillis]

The biggest factor towards overall mpg is actually engine size, not aerodynamics. Gasoline engines have to run at their ideal power to stay efficient, induction motors do not (for the most part). You're eyeballing the wrong places if you're getting 40 mpg. Compare a BMW 5, 6 or 7 series- 19/27, 21/30, and 21/29 mpg. 25 is, if anything, optimistic. The only cars that get 40 mpg are subcompacts and some compact cars. 25.5 is a good balance between all of the small cars and the SUVs/pickups, because the Model S is between them in size and weight. In fact it tends towards the upper end- although it is very aerodynamic, it is a quite large and quite heavy car.

When the model 3 comes out, we'll be able to make better comparisons to high mpg ICEs like the fit, fiesta and civic.

[the8472]

The comparison is not quite that easy. The old petroleum infrastructure is more centralized.

You can get electricity almost anywhere, adding a charging station to parking places or garages is far easier and safer than hypothetically laying gasoline pipelines everywhere. So there are more opportunities for partial charging when the car is idle.

[kirushik]

> easier and safer than hypothetically laying gasoline pipelines everywhere

Ironically, that's safer exactly because electricity won't give you those MW-scale powers.

[cypherpunks01]

What do you mean "laying gasoline pipelines everywhere"? Gas stations do not connect to any utilities apart from the regular electricity, water, and natural gas, all of which require a physical connection to centralized infrastructure.

[the8472]

A hypothetical scenario where we have the gasoline equivalent of charging columns at parking places or garages and distribute gasoline to them like we do with electricity.

[PietdeVries]

And in addition: the efficiency of a petrol-engine is much lower than an electric engine. So you perhaps only take in half of the fuel, if it gets you just as far you have what you need, isn't it?

[vvanders]

Not quite, ICE engines are governed by the Otto cycle which has a theoretical efficiency limit of ~37% and most get less than that.

In terms of real-world power usage you're close to 1/3rd of that(unless the car captures the excess heat and reuses it).

[iheartmemcache]

If we're talking 'next-gen' tech vs 'next-gen' tech, let's be a little fairer, newer cars are using the Atkinson not the Otto[1]. Throw in the fact that we're no longer tied to a camshaft for timing[2], cylinders can be shutdown at will (e.g. you're in bumper-to-bumper on the 405 or 101, your Benz-AMG or Stage 3 Mustang doesn't really need all 8 cylinders firing) and the fact that most manufacturers have at least one car with the option to reclaim that heat (i.e. even Ford Mustangs, notorious for being gas guzzling pony cars, have a turbo-hybrid configuration option) and things for the ICE look a little less bleak.

I'm all for pure-electric cars but we're still a long way from Joe the miner in Kentucky from being able to drop $1800 on a 2000 Toyota Tundra and having it be able to get him reliably from the jobsite and back. That's not even factoring in the whole capacity-decrease-with-use (and even non-use-- deterioration occurs simply by just storing cells at full capacity for long duration -- of lithium.

Even with the best, most conservative profiles on a battery-module controller for anything lithium based, good luck getting > %50 of cell capacity 5 years down the road of a daily driver [edit: 7]. Anode deterioration (at least, last I seriously researched it for projects requiring portable units for driving larger loads than an average car was ~1.5 years ago) was still a problem even in the lab.[3]

My sister abuses her 2004 Civic coupe to the point where I think she's still running a stock air filter and runs 30-35k between oil changes[4]. This was a run of the mill car she's had since god-knows-how-long and she's still getting 22mpg city [5] ~26 highway on an automatic transmission.

tl;dr -- In terms of total costs :

- capital (purchase) / delivery fee

- operational ($ of petrol for ICE per unit travelled/$ of energy from your power supplier per kw/h), insurance

- maintenance (tire wear, brakes, battery module(s) replacement(s)) over, eh, 5 years from out-of-the-showroom-into-your-garage, I'd be surprised if you saw the electric dollar-for-mile-traveled outperform it's ICE counterpart.[6] I'm far from the forefront of Li, but I do have a few friends in that field (both in academia and in industry) -- even the most optimistic don't see pure-electrics reaching a TCO parity point of an ICE for the consumer in less than 10 years.

--

[1] http://www.greencarreports.com/news/1091436_toyota-gasoline-...

[2] https://www.youtube.com/watch?v=FJXgKY2O4po FreeValve as explained by that really enthusiastic "Engineering Explained" 24 year old automotive engineer, dumbed down to the point where even I can grok it.

[3] Rumor had it, DARPA was using some crazy proprietary stuff that managed to completely nullify dentrification, but if they've managed to accomplish that anodic behavior, there's no way it's going to be released for public usage -- rather, it'll remain hush-hush minus 50 PhD's in metallurgy, and Lockheed drones all of a sudden posting performance numbers +30% from the last revision.

[4] She's not using those long-lasting synthetics that have additives to SeaFoam (yeah, I'm using it as a verb) out carbon build-up on the cylinders and what not, in case you're wondering. Just cheapo 5w/30.

[5] That, albeit was with me driving in 'conservative' mode rather than "hmm let's see the 0-160 on this McLaren".

[6] And I'm 100% sure if you bought a 3 year old variant of an ICE vs a pure-electric, it's no contest -- https://www.edmunds.com/car-buying/drive-a-nearly-new-car-fo... -- ignore the link bait title, it's just about the FMV of cars as a function of time.

[7] In addition to the response I made directly to child-poster, I'd like to concede that it is very possible he's ran 43k miles (i.e., literally at least a thousand cycles, likely closer to mid thousands) with a retained 98%. He makes a very valid point in bringing up the variance of cell capacity deterioration. I'd genuinely love to see some cal'd equipment with your standard dummy load and power analyzer log setup to see the data. (I ain't no fancy electron whiz but I can read me a chart or two.)

The take away is that overall capacity is a function of usage. I could probably get in the lab and simulate 43k miles of load in LabView discharging/recharging every 10 miles while keeping the thermal properties controlled as all heck and see 99.5 capacity retention, but these, again, aren't Joe's driving patterns.

edit 2: @maratd: See my edit 1/[7] (which I presume I was writing while you were drafting your response). I think we're largely in agreement re: usage properties being highly influential. My response to the OC (original child poster) addresses the deep-cycling cooling. As this has turned into a post with 8 endnotes, I think I've crossed the threshold of reasonable discourse.

Allow me to close with a quick remark re: BMC's on your power drill. Anything half decent will have active thermal monitoring specifically because of the reason you stated (much to the chagrin of blue-collar workers everywhere). "Ok, last weld before quittin' time..." paddle trigger actuates, worker expects wire-wheel to start spinning a to clean the slag of iron oxide off the root weld. nothing happens because the thermocouple on the motor armature triggered a lock-out "PC LOAD LETTER WHAT THE HELL DOES THAT MEAN?"

[vvanders]

Not sure where your getting your 50% degradation numbers from, I have 2 years of daily use, 43k miles and only ~2% degradation.

[iheartmemcache]

(old-ish study, apologies, but was cutting edge circa 2010, but still stands re: LiFePO2 which I'm betting your '14 production car is using) -> http://ecec.mne.psu.edu/pubs/2010-zhang-jps.pdf Page 2, Column 2, Figure 1, Top chart. 300 deep-cycles @ ~92%, 600 @ 74%.

If you're the average SV guy who 'daily drives' his Tesla 20 miles from Oakland to his lofted startup where there's 220 to full-charge before you go home, you'll get 2%. Johnny in Kentucky working the coal miles doesn't have that luxury and will certainly enter into 'deep charge' consumption. (600 cycles -> ~75%, with 2nd deriv of batt life w/r/t cycle being negative, i.e., progressively decreasing losses).

Again, not in the field professionally, but these opinions are consistent with my friends who are working at the forefront (albeit, a statistically small sample space, I openly concede !)

[toomuchtodo]

Tesloop, the transport company that'll shuttle you between LA and Las Vegas via Model S, has only seen 6% degradation over 180k miles on their vehicle; this is with ignoring Tesla's advice not to charge to 100% every time at Superchargers.

Your pack longevity math is grossly inaccurate.

[vvanders]

If by daily driver you mean weekly 300mi weekly roundtrip that usually ends around 5-10% and ~30 miles a day otherwise then sure.

My numbers line up with what most Tesla owner experiences. If your friends are at the forefront of the profession then I'd be a bit worried about whoever they're working for.

[maratd]

> good luck getting > %50 of cell capacity 5 years down the road of a daily driver

The data doesn't bear this out. Users have been seeing 5%-10% degradation over the first few years, after which point it levels out.

After 10 years, I expect to have >80% of capacity still usable.

The enemy of lithium ion is high state of charge, as you said, and high temperature. Tesla gives you control over how much you charge the battery, so you can easily avoid a high state of charge.

The big deal is temperature. Your laptop, cell, power drill, etc. do not have temperature control. The battery overheats frequently and capacity suffers, until the battery is dead. Tesla has an active liquid temperature control system in the battery pack. It cools the battery when it heats up and heats it up when the pack is cold, keeping the temperature under control. This preserves capacity long-term.

[antisthenes]

> After 10 years, I expect to have >80% of capacity still usable.

It's pointless to talk about capacity at year X without accounting for range, your driving habits and miles/year.

Capacity loss is not a dependent variable of just time, but most importantly of the number of recharge cycles. This is why Nissan Leaves (especially 1st gen ones) have experienced huge capacity losses when used as daily drivers (think 30% loss @ 50,000 miles). Depending on how long it takes you to drive 50,000 miles, the time frame can be as short as 3 years.

Of course a Tesla needs fewer charges to go 50,000 miles, but that obviously comes with a huge price premium over the 'economy EV' like a Leaf or a Kia Soul or what have you.

[maratd]

> but most importantly of the number of recharge cycles.

That was the point I was alluding to. You're mistaken in thinking that this is the most important factor. It isn't. The most important factors are extreme states of charge and temperature. If you account for those and control those, you can easily go a million miles on the battery pack without any kind of major issues. The rest of the car will fall apart before the battery pack gives out or suffers major degradation.

[vvanders]

Capacity loss for leafs come from their lack of thermal management, not driving range. See the issues they have with capacity in warm climates.

[drzaiusapelord]

On the flip-side I don't have a gas station in my garage or my work's parking garage, but either can be trivially outfitted with a 220v plug. Ideally, one's recharge strategy shouldn't be like filling up a gas car. You should be plugging your car in for overnight charging and only using these types of stations in a pinch. With gas cars, I have to use these stations. They're literally my only choice. I couldn't build a gas station in my garage even with vasts amount of money due to regulatory, safety, and environmental concerns.

Its also more reasonable to tap into overnight power as to not stress the daytime powergrid.

>gas contains about 33kWh of energy per gallon

ICE are about 20-30% efficient. So 70% of that 33kwh is lost to heat and other inefficiences. Electric cars are about 70-80% efficient, so you actually need only 1/3rd the energy capacity in this kind of calculation to match ICE/gas.

[ebbv]

The thing to keep in mind when thinking about EVs is that while they may be slower to fill up at stations where you have to stand there like the Tesla super charger stations, this is a small minority of the charging most EV owners do.

Most of the time my LEAF gets charged at home in my garage. We only use public chargers a handful of times per year. When we do, it's stations in parking garages or public parking lots. Which means we plug it in and walk away. We don't have to stand there with it while it charges. If it takes a couple hours that's fine.

People focus on how fast they can recharge their EVs while they are standing there waiting for them because they are used to having to go somewhere to refuel their gasoline powered car. One of the great things about owning an EV is you recharge at home.

[niftich]

While all of this is true, charging time is an issue because it limits range. A gasoline powered car is just a 5-minute detour away from doubling its range, which compares terribly with the sort of vehicle you're going to want to walk away from to do something else while the charging does its thing.

Apparently people leaving Teslas longer than necessary in the supercharger spots is already an issue [1] that they are trying to rectify by charging for overstays.

[1] https://news.ycombinator.com/item?id=13204120#13204455

[ebbv]

It's true, if you are the type of person who often drives >200 miles a day EVs today are not as convenient as gas cars for those trips.

But that is a very small percentage of people. If only those people bought gasoline cars in 2017 they would sell fewer than the number of EV cars sold in 2016.

[pbz]

Except that Tesla is now charging $0.40/minute of leaving the car plugged in after a full charge is reached. They do this precisely to prevent people from "abandoning" their car while others wait in line.

[ebbv]

That's because Tesla's supercharger system is designed to work more like the refueling system people are familiar with and comfortable with; pull up, plug in, wait for it to finish and then drive away.

One of the beauties of EVs is not having to use that style of system. The superchargers are nice but most of the time you won't use one unless you're regularly driving over 200 miles a day.

[greglindahl]

I totally agree that almost all Tesla charging doesn't happen at superchargers. But where did you get the idea that anyone intended that owners should stay with their cars while charging? I've only seen that when nearby services are closed. Tesla has always advertised services nearby superchargers, and now that's visible on the in-car display.

[greglindahl]

If I'm eating dinner nearby, it's easy to run out and move my car, or, there's a valet to do it at overly-popular superchargers. The Tesla phone app gives plenty of warning.

[ajross]

That's only doing the math on the instantaneous flow rate down the nozzle/plug. Pulling into the station, waiting in line, hitting the rest room and paying the bill need to be included too to get a relative penalty.

Also: if that 33kWh/gallon number is a heat of combustion (I'm too lazy to convert to real units or look it up myself) the efficiency gains of an electric motor vs. an internal combustion engine is significantly higher than 3x, I believe.

[phil21]

> Pulling into the station, waiting in line, hitting the rest room and paying the bill need to be included too to get a relative penalty.

This is not the average experience for a US driver. Very few gas stations ever have all their pumps utilized, even during rush hour. I haven't gone into a gas station in years, or waited on paying the bill - everything is automated at the pump.

I would put the "convenience store" aspects at par - you either want some snacks or need to use to rest room or do not - the fuel type doesn't change that.

Payment again I'd put at par - swipe a credit card at the "pump".

Maybe add a minute for "average wait for a free pump" to the gas station model, but I'd argue that problem would be even worse (or at least par) with electric charging.

The only real win I can see is that you could do other things away from the vehicle while it charges (attended vs. unattended fueling) which lets you parallelize some activities above. But that only becomes useful once the refueling times become within the average potty/snack break at a gas station - and we're no where near there yet.

[theandrewbailey]

> Very few gas stations ever have all their pumps utilized, even during rush hour.

The ones operated by grocery stores (giving gas discounts on $X of groceries bought) are always full during rush hour.

[ajross]

You're overcomplicating. Take a stopwatch. Start it at the point where you exit your normal driving routine to "get gas". Stop it when you resume. Take that time, subtract the time spent actually pumping fuel (which even in your convenient utopia is still going to be less than 1/3 of the total), and add the time spent to equivalently charge the vehicle.

Then divide the two totals to get a relative penalty to an electric car. If you're doing the analysis any other way, you're almost certainly doing it wrong.

[saurik]

Yes, on average this would slightly affect the result, but I'd be shocked if a non-negligible number of trips to the gas station for most car drivers involved entering the convenience store, particularly to "hit the restroom". Most people spend their lives driving back and forth between two places that have clean and (certainly relatively to a gas station) pleasant restrooms: the only people stopping at a gas station are on long road trips; and while I do a ton of these, I'm still usually not doing it a gas station: most people are probably stopping at whatever their favorite fast food restaurant is and going to the bathroom there, which satisfies their food craving at better cost efficiency than the overpriced even lower quality junk at the gas station and, at least today, doesn't parallelize that well with either filling their gas tank or charging their battery. (And except during small windows of time when only desperate people are getting gas, there generally are not lines at gas stations.)

[ajross]

> I'd be shocked if a non-negligible number of trips to the gas station for most car drivers involved entering the convenience store, particularly to "hit the restroom".

I'm going to contend you're exactly wrong, actually -- literally backwards.

For an electric car, routine fillups don't actually exist. You charge it at home and it's always "full" for commute trips.

Electric service station visits happen on long trips. Notably, so do bladder full exceptions and blood sugar shortfalls.

[amelius]

Can't we have "charging lanes" embedded in major highways, and cars fitted with retractable sliding contacts? Or something like that?