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Electric Propulsion's Dirty Secret: Why Lithium Can't Fly (Or Float) Profitably

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Re: Electric Propulsion's Dirty Secret: Why Lithium Can't Fly (Or Float) Profitably

#91

Post by zik »

His estimate the LCoE of an electric vehicle with lithium batteries is off by a factor of ten. My back-of-the-napkin calculations make it to be $0.22–0.25 per kWh.

Let's compare two vehicles - an EV car vs an ICE car - in terms of their energy costs per mile, including energy storage. Using the above numbers the EV comes out to around $0.07 per mile including the lifetime costs of the battery, and the ICE comes out to around $0.125 per mile.

In short - his numbers are completely wrong and when calculated correctly prove the opposite of what he's trying to say.

Re: Electric Propulsion's Dirty Secret: Why Lithium Can't Fly (Or Float) Profitably

#92

Post by londons_explore »

For the marine uses specifically, the use of hydrofoils promises to dramatically reduce the amount of energy needed for movement at any decent speed.

Previously hydrofoils weren't used because they rely on complex feedback mechanisms to maintain ride height despite waves etc.

Sure, someone could pair hydrofoils with gasoline engines, but I suspect they won't, and that means hydrofoil+electric will win out over conventional hull+hydrocarbon fuels for a bunch of use cases.

Re: Electric Propulsion's Dirty Secret: Why Lithium Can't Fly (Or Float) Profitably

#93

Post by api »

numpad0 wrote: post #85
api wrote: post #48

I remember seeing loads and loads of analyses like this back in the 2000s on a site called The Oil Drum about why electric cars would never work at scale. (Spoiler: My family has two EVs.) They always assume that the technology will never get better, that industrial economies of scale don't exist and therefore that prices don't decrease with scale, that currently developed reserves of resources like lithium equal tot…

> They always assume that the technology will never get better, that industrial economies of scale don't exist The technology hadn't improved not much more than a quarter's worth so far in my lifetime as far as EV is concerned. Wh/kg figures hasn't changed, even fusion seems closer than solid state batteries, mileage figures for EVs is same 4mi/kWh, battery recycling still hasn't been figured out. They can't even rec…

Computers have psyched us out. There is no other technology in human history that has ever seen a capability growth curve like Moore's Law. Even aviation, which went from biplanes to moon landings in 50 years, doesn't compare.

Still, there has been huge improvement in batteries. The main improvement has not been in energy density but in cost. Find some graphs of battery cost per kWh of storage. Storage cost has dropped by almost 10X in the last 15-20 years. Reliability and rapid recharge capability have also increased a lot.

Still, for medium to long haul aviation we probably would need at least a 3-4X improvement in energy density per unit volume and mass, and I don't see that happening soon. It's likely that long range aviation is stuck with liquid fuels for the foreseeable future. But as I said it's only 7% of oil consumption. We should just let aviation keep going as-is and cut fossil fuel use in terrestrial transport and power generation.

Part of why we're not recycling batteries much is that lithium isn't expensive enough to make the investment in it profitable. The major cost in batteries is the manufacturing process, not the lithium itself. If lithium prices go up there'd be an incentive to figure out recycling.

Re: Electric Propulsion's Dirty Secret: Why Lithium Can't Fly (Or Float) Profitably

#94

Post by svnt »

seszett wrote: post #88
toast0 wrote: post #38

I suspect that there's niches where battery electric boats and maybe planes do make sense. My state's ferry system is investing in electrifying, because they project it reduce operating costs. The 'easy' part is moving towards hybrid systems that can move with diesel or battery; this is projected to save fuel even without shore charging. The hard part will be making shore charging work. Our grid is mostly hydro, so s…

We also have electric ferries here in Antwerp and Ostend. I don't think they're hybrid, although it's not clear when they get charged, I would assume during the wait times (about 15 minutes wait and 5 minutes ferrying) but I have not noticed them actually connecting anywhere, maybe I just haven't noticed though. The communication says it can sail for three hours on batteries, so they must charge during the day while…

Most of them seem to perform opportunity charging (while loading/unloading), using direct rapid charging via pantograph.

See eg https://www.energymonitor.ai/sectors/transport/the-secret-to...

I have also seen designs for ferries to wirelessly charge underwater while docked.

Wireless charging can be quite efficient when the two halves comprise nesting physical features with similar tolerances to actual transformers. But I have not seen this implemented, presumably due to biofouling problems.

Re: Electric Propulsion's Dirty Secret: Why Lithium Can't Fly (Or Float) Profitably

#95

Post by neuroelectron »

refulgentis wrote: post #80

This is a really nice article, in that its long and provides a good example of knowing everything yet nothing. Setting aside individual problems with it, this is because it suffers from a broad and blindingly obvious problem: investment is occurring in this area b/c it will be absolutely politically unpalatable in 20 years to still be emitting CO2. A long analysis showing lithium is more expensive than just using gas…

What's wrong with CO2? It's not a serious issue, it's just an easy proxy for real environmental damage, focusing on CO2 simplifies complex issues like deforestation, pollution, resource depletion, and actual toxic emissions from the rest of the world. The idea is we're going to implement another tax on the plebs to drive a carbon economy and that will compensate for the damage the elites and 3rd worlders are doing. Then on top of that all the other inherent taxes like lithium batteries, transmission, windmill subsidies, solar recycling, and so on. And of course, this has to be done on the back of the most productive people in society because who else is going to do it.

Re: Electric Propulsion's Dirty Secret: Why Lithium Can't Fly (Or Float) Profitably

#96

Post by staplung »

jmward01 wrote: post #9

This appears to ignore the new technology that electric brings in: Reduced maintenance, (for aircraft) reduced weight in other parts of an aircraft, new propulsion capabilities that increase efficiency of the energy used, new performance envelopes (like flying much higher because the physics are totally different), etc etc. Sure. Take an existing vehicle optimized for burning things and just swap that small part and…

Other than potentially reducing maintenance costs, I'm not sure any other part of this stacks up. I don't see how electrification would allow you to save weight in other parts of the aircraft. I don't think electrification adds any new propulsion capabilities that are more energy efficient, not for airplanes or boats anyway. For boats, the electricity would still be turning a screw and for airplanes the only method of propulsion that would work is an old-fashioned propellor. That last is the same reason you can't fly electric planes in new performance envelopes: prop planes can't get that high and wouldn't work if they somehow found themselves up there. Even turbo-prop planes (which have gas turbines that enable them to work more efficiently at high altitudes) are limited in altitude by the fact that the tips of the propellors are going very nearly the speed of sound.

Re: Electric Propulsion's Dirty Secret: Why Lithium Can't Fly (Or Float) Profitably

#97

Post by ted_dunning »

DickingAround wrote: post #49
chris12321 wrote: post #7

I recently read The Ministry for the Future by Kim Stanley Robinson, and one of the ideas in it that I thought was very good was replacing our cargo ships with wind-powered ships, basically giant sailing ships. In the book, they were incredibly slow, with shipments taking months to complete, but if supply lines were set up correctly, that wouldn't matter for a lot of cargo. Cargo ships are a massive CO2 contributor,…

We should not under-estimate the need for speed in supply chains. Predicting future demand is hard. To be more specific, we're talking about predicting ~100M unique products (the order of magnitude that moves on the pacific) and some of them have very lumpy demand (e.g. invent a new product, but it depends on 100 other obscure products).

We should also not over-estimate the need for speed. Just because some items need speed, it does not follow that all items need speed.

Re: Electric Propulsion's Dirty Secret: Why Lithium Can't Fly (Or Float) Profitably

#98

Post by svnt »

toast0 wrote: post #38

I suspect that there's niches where battery electric boats and maybe planes do make sense. My state's ferry system is investing in electrifying, because they project it reduce operating costs. The 'easy' part is moving towards hybrid systems that can move with diesel or battery; this is projected to save fuel even without shore charging. The hard part will be making shore charging work. Our grid is mostly hydro, so s…

An analysis of the Nordic ferry systems ten years ago found that 70% would benefit from electrification —- about 45% could go fully electric, while about 25% made more sense as hybrid.

This means for them 30% didn’t make sense to electrify.

This was Siemens making the case for selling electric boat parts, so presumably this was best case at the time.

Re: Electric Propulsion's Dirty Secret: Why Lithium Can't Fly (Or Float) Profitably

#99

Post by lolc »

sokoloff wrote: post #12
metalman wrote: post #5

lithium is most definitly profitable in thousands of applications including boats, and light aircraft, now. The intercontinental heavy aircraft, and marine segment is not there yet, but there is a lot of progress bieng made every day, and every single major player in the transpotation sector is watching closely, as the chance of a disruptive battery technology de-stealthing is significant

Aircraft getting lighter as they burn off fuel is a feature. Lithium energy storage doesn’t get lighter as it discharges, meaning the aircraft doesn’t get more efficient as stored energy decreases and the landing weights/speeds are higher than a comparable fossil fueled aircraft. I’m more hopeful that synthetic jet fuel will be a practical solution than batteries for long-range flight.

> meaning the aircraft doesn’t get more efficient as stored energy decreases

While I read that, I imagined booster packs detaching from airplanes when they reach cruise height. In my mind they look like heavy quadcopters stuck to the wings. They would cycle back to the airport for charging before assisting the next climb.

Re: Electric Propulsion's Dirty Secret: Why Lithium Can't Fly (Or Float) Profitably

#100

Post by 0xbadcafebee »

I came to the comments hoping for lots of electric apologists not reading the article and I was not disappointed

As a recap (for those who don't like to read)

- 70% of EV cost comes before the vehicle ever moves and must be recouped over the life of the vehicle (and takes much longer than traditional fuels)

- the energy density & cost of certain fuels is the only reason certain vehicles are able to be profitably operated in the first place

- the only way to create enough energy to match said fuels/demand with electrics (at present) would be to hook up coal or nuclear plants to airports, and even then it'd be expensive as shit

- we basically need a 5x improvement in battery energy density at minimum to even think about profitability, and that's only one of the things that would need to be addressed before it's practically feasible

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