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

He is for some reason comparing the levelized cost of energy. This is a metric used to analyze energy generating devices, not energy consuming devices.

His tweet says that if you wanted to buy electricity from an electric scooter and use it to run your house, it would cost the utility providing it $2 to $5/kWh, assuming that the sole function of the scooter is to provide its electricity to consumers directly.

LCOE goes up the further you get from the source, but his analysis is also based on outdated numbers and largely wrong.

That said, he isn’t totally wrong. Electric marine has a tough road ahead of itself due to the inefficiency of boats relative to cars. Boats can be calculated roughly as a car that is always going somewhat uphill.

Electric planes are a niche use case for the foreseeable future.

Was going to post something similar. I love me a screed where the author rails against some group saying they don't know what they are talking about, and then goes on to demonstrate that they don't know what they are talking about. :-)

For a long time I didn't understand what 'talking past each other' meant but this article is a good example of that. Mostly it's bad form to make sweeping generalizations. But let's be specific;

From the article, here is the "TL;DR" --

Lithium propulsion for aircraft and boats is fundamentally unprofitable across the entire U.S. grid. The numbers don't lie: 60× worse energy density than jet fuel, 3.3× higher operating costs, 22% reduced asset utilization, and payback periods that consume 2/3 of the asset's lifespan. Anyone claiming otherwise is ignoring basic physics or hiding most of the energy and economic costs.

So first let's talk definitions. "profit" is, by definition, "gross revenue" - "costs". "costs" come in two flavors, "direct", "marginal", and "operational". Direct costs are what you pay, every time for the thing you need. Marginal cost is what you pay for just "a bit more" of the thing you need. And operational costs are the costs you pay so that you can operate your business.

So there is a direct cost of a lithium battery which is included in the manufacturing of a widget, there is the marginal cost of charging that battery up to full capacity, and there is the operational cost of maintaining the battery and presumably repairing or replacing it, when it doesn't do what you ask of it any more.

There is a fourth cost, which is "externalities", that covers the cost of remediating the environmental damage which is done by your energy source and while important, and the focus of climate change awareness, its rarely considered in the discussion of 'profitable' vs. 'unprofitable.'

If we keep this discussion on "lithium" which is the "gas" of these transportation modalities. You can say that building a battery pack is much more expensive than building a gas tank. So cost wise a gas is cheaper. The marginal cost of energy in Watts between gasoline and electricity leans heavily in electric's favor for a number of reasons. The operational costs of fueling and maintaining the "source power" for electric cars nominally similar.

But all of that, has to be put into the context of the system cost which includes vehicle fabrication, power 'converters' (aka motors) that turn fuel into motion, and mechanical maintenance.

Then you jump into a bigger frame of reference and consider all transportation modalities and how they combine as a system to get someone from point A to point B, and what are the costs of building, expanding, and operating that?

The author doesn't see a path between 'here' and what they know to 'there' where Lithium batteries have "improved" non-vehicle transportation modalities over what fossil fuels can do. That's fair, I don't see one either precisely, but there are interesting paths to explore. Foreclosing one's thinking to possibilities on those paths is not usually the right thing to do. A better strategy is to think about it in terms of what would have to be true in order for these paths to be viable updates to the way we travel/ship/transport.

Driving it full speed is how you drive these things. They are safer when the speed delta is minimal between you and the rest of the traffic and you are charged by the minute so the incentive is full speed short of obligatory stopping for traffic lights or stops (really blown through) or slight slowing for turns.

Battery estimates fwiw are very optimistic on the app in my experience. Assume error of 1/3 in range to be safe.

It took my wife and I actually buying an electric car and running it for a few months to actually convince family members that electric cars are a worthwhile technology.

They were fervently against us buying one, so much so that we had to avoid conversation about it and outright lie to them about our intentions.

"You can't take it on a driving holiday."

Yeah, we'll manage with one of our other two existing cars for that, like we have when we've taken one of our previous once every couple of years driving holidays.

"You can't tow with it."

Thank fuck, I hate towing and I can't remember towing anything in the last 15 years.

The electric car, a Nissan Leaf, is perfect for 99% of our use cases. The whole family love it. It's our "first in best dressed" car.

Even smart people are fucking stupid about plenty of things.

> Let's compare two vehicles - an EV car vs an ICE car -

Ok, but TFA is about planes (and boats), not cars. That's a big caveat because neither planes nor boats can do regenerative braking, and planes need to be light. Boats can get big enough to float even if the power plant is heavy, though there is a maximum to what is reasonable.

Another way (from first principles): Assume you buy two cars per driver. The driver parks one car at their solar panels at a time, so one is available for use 100% of the time, and at least one can charge off the panels 100% of the time.

Assume a 10kw solar system with no batteries, but with a level 2 charger. That costs $28K this year. Assume $50K per car. The system cost is $128K.

Assume the climate is such that you can charge the cars at 6kw (max output of the charger) for an average of 8 hours a day (pessimistic in summer, optimistic in winter).

This setup should last about 10 years. (Or sell the cars after 5 and get money back for new cars.)

That’s 365 * 10 * 8h * 6kw usable for the cars, or 175.2MWh, giving us $0.73 per kWh. Clearly the sky is falling. I’m going to get a steam engine for my buggy!

I forgot to figure the depreciation of the cars. We wasted one because this scheme is dumb, so the depreciation for an equivalent ICE car would be zero. For the other car, I think it’s reasonable to assume 90% depreciation. Say the ICE car depreciates $40K. We can sell the two EVs for a total of $10K. Now the total cost (sans car) for the system is $78K, or $0.445 per kwh — cheaper than California’s grid.

I forgot to figure interest on the $78K of capital. At 8% average return, that’s a bit over 2x, getting it closer to a dollar per kwh.

For a 4 mile/kwh car, that’s $0.25/mile. Of course, if you assume the existence of civilization, then the price drops a lot. For instance you could only buy one car, and you could size the solar smaller, or also plug the house into it.

Anyway, in my hypothetical mad maxian hellscape that’s experiencing healthy, steady economic growth and has access to cheap refined gasoline, he’s still off by a factor of 2.5x.

There is a cute little two-seater electric airplane used as a trainer.[1] Gets about 50 minutes on a charge. EHang has demonstrated 48 minutes of flight with their flying car (a 16-rotor drone). Expect to see those at the 2028 Olympics, ferrying VIPs around Los Angeles. But energy density is too low for long trips.

[1] https://www.pipistrel-aircraft.com/products/velis-electro/

> reduced weight in other parts of an aircraft

The bigger problem is that the overall weight increases. Rearranging the COG doesn't really matter when most of your energy is spent literally fighting gravity.

This is the first thing that popped up in google when I wanted to compare gravimetric density between gasoline and lithium ion batteries. Gasoline is still approximately 30x denser. That is at least one revolutionary breakthrough in battery technology away, if not several.

https://research-archive.org/index.php/rars/preprint/downloa...

"Additionally, that 60x claim is getting old by the minute. We are getting to 300+ with advancements coming in so fast they are hard to keep track of. That 60x could drop to 10x or lower in just a few years"

What was a Tesla Model S power density 10 years ago? Today? Hardware moves slower than you think. All your points have some basis of consideration but the potential performance improvements they represent are tiny compared to the single huge downside of having to fly a giant, heavy battery everywhere and that is not going to change anytime soon.

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.

Lithium cannot get much denser in energy storage, sorry. Even 10x denser than jet fuel is still way too heavy.

Where I live companies are moving to electric ferries because they’re cheaper to operate, require less maintenance, and are much quieter for the passengers. Plus they don’t emit any exhaust fumes while idling at the dock.

The port also has an electric tug boat, which their reports say is very handy because it changes power output much faster than diesel tugs. Charging times are not a factor according to their reports.

Our power grid is 80+% renewable though.

Of course the article ignores that it’s easier to improve the emissions of a few large powerplants than every car, ferry and scooter, and that the minerals in batteries don’t disappear after use.

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.

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 operating.

And at my other place around Nantes they're building a new ferry that is supposed to be hybrid electric/hydrogen. I'm not very optimistic on hydrogen though so I don't know. The latest info say the budget has tripled and the delivery has been reported from 2026 to 2030.

Hot swappable batteries!

Probably not. Hydrofoil boats work OK, but few applications need the speed. The US Navy went through a period of hydrofoil enthusiasm, and built some.[1] Boeing built a hydrofoil ferry, and some are still in service. The Navy version used 10x as much fuel per hour in hydrofoil mode, running off a gas turbine. Of course, it was going fast in that mode.

[1] https://www.youtube.com/watch?v=zQ2sSRBMPqs

They use t foil catamarans on the catalina express route. Diesel engines and water jet not gasoline though. Ride is about an hour to avalon from the port of long beach.

Currently, ships need human sailors. They perform maintenance aboard ship as well as have legal oversight of the craft. We are not yet able to replace the crew with automation.

It's difficult to find skilled crewmembers willing to sign up to extremely long rotations away from home.

Or Nuclear Propulsion:

https://en.wikipedia.org/wiki/Nuclear_marine_propulsion#Merc...

> Nuclear ships are currently the responsibility of their own countries, but none are involved in international trade. As a result of this work in 2014 two papers on commercial nuclear marine propulsion were published by Lloyd's Register and the other members of this consortium.... > This is a small fast-neutron reactor using lead–bismuth eutectic cooling and able to operate for ten full-power years before refueling, and in service last for a 25-year operational life of the vessel. They conclude that the concept is feasible, but further maturity of nuclear technology and the development and harmonisation of the regulatory framework would be necessary before the concept would be viable.

> In December 2023, the Jiangnan Shipyard under the China State Shipbuilding Corporation officially released a design of a 24000 TEU-class container ship — known as the KUN-24AP — at Marintec China 2023, a premier maritime industry exhibition held in Shanghai. The container ship is reported to be powered by a thorium-based molten salt reactor, making it a first thorium-powered container ship and, if completed, the largest nuclear-powered container ship in the world.

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).

> if supply lines were set up correctly, that wouldn't matter for a lot of cargo.

One of the big problems facing logistics across the board is just optimization. But at some point, you run out of intuition to uncover more efficiencies. This space is actually a really good use for AI. In fact, it's even useful for predicting what to put on that boat ahead of when it's ordered/purchased (up to a point). So yes, longer shipping times might not be that big a deal for non-perishables and frozen products.

> Cargo ships are a massive CO2 contributor

Not really. They’re 1.6% of global emissions if I multiplied the numbers on this page out right. The table says they’re 20% of shipping emissions, and the intro says shipping is 8% of global emissions (excluding ports and warehouses).

This result seems surprising until you realize that semi trucks produce 100x more CO2 per kg-mile of cargo.

https://climate.mit.edu/explainers/freight-transportation

There's nothing stopping it, here's a link to an article from 2023: https://www.bbc.com/news/technology-66543643

Why can't cargo ships deploy floating solar panels to power the ship motors?

We probably don’t have the physical space to onshore 6x the capacity in warehouse or whatever it would work out to around ports. Short of multilevel warehouses but I mean containers have been stacked 5 high since covid around the port of LA and I think that is about the limit without some significant rethinking of process. Maybe the ships could just anchor off shore for longer and function as the warehouse.

His beef against physicists is likely rooted in confirmation bias. Musk has a BA in physics that some debate if he even completed, but one bad egg does not prove the rule. It would be just as easy to point out engineers who have gone on to lead dodgy enterprises but, again, a few bad eggs do not prove the rule.

His reason for attacking another group is likely to make his own group look superior. This works on the playground and in more professional situations than it really should. He might also just be airing his prejudices thoughtlessly.

Either way, it's probably going to limit the audience he reaches and invite some nasty responses. He'd do well to avoid spewing such nonsense in the future.

but the metric the OP was using was power density. nuke fuels are MUCH more energy dense than hydrocarbon fuels. but putting a reactor on each plane would probably have negative externalities.

but mixing your comment with a few others, maybe a nuke plant on the ground that cracks the co2 in the atmosphere to make carbon neutral hydrocarbon fuel.

One possible path is the hybrid aircraft, where combustion turbines or fuel cells produce electric power that drives small ducted fans via electric motors. The enabling technology here is superconductors. Airbus is working on superconducting motors and generators for such hydrogen-powered aircraft.

One can imagine regenerative braking in the fans, for example to recover energy as aircraft descend, and also with batteries providing emergency backup power.

The math would already change quite a bit if airplanes had to play on a level playing field. For example, in the EU there are no taxes on aviation fuel. For a country like Germany that's the equivalent of a yearly 7 billion euro subsidy.

Add fuel taxes and CO2 surcharges, and same-continent rail travel suddenly becomes a lot more attractive!

Fair point, check the post again, I've posted on twitter about the benchmark for productively profitable venture and PE dollars.

It's our taxpayer dollars at work.

As a public market pegged to the same grid constraints, I prefer $POWL over most of the private lithium companies being pitched.