tldr: There's a lot of bullshit going on right now about Lithium propulsion boats and planes, don't trust the energy return on investment or viability of its profitability...it's fundamentally a net negative energy return on investment.
Edits* - there's a hacker news thread where I'm getting roasted by programmers, I'll survive. Profitable = productively profitable for the amount of PE or venture capital invested when benchmarked against other relevant assets with the same grid thesis.
There's a lot of mids who will argue about LCOEs being wrong but they never propose an alternative to their overly optimistic capacity factors, neglect of degradation and replacement costs, and inconsistent-or excluded charging costs(grids matter).
Elon lies through his teeth and boldly in a room full of people.
Physicists Get Too Much Street Cred and Access to Venture Capital
I've often opined that physicists are the ultimate fauxdustrialists. Readily able to lie at a moment's notice. Many refer to themselves as "polymaths."
I think the physicist mindset has infected a large swath of venture capital with delusions about what's possible with lithium ion battery technology.
Long Live EROI analysis, even if I'm off, I'm not off by a factor of 10-100.
Physicists more than any other field of people I've encountered make claims about subjects far beyond their max competency because of the cockiness induced when they were able to complete mathematical proofs that allowed them to grok logic puzzles, digital signal processing, and physics as an entire subject with ease.
They never faced the analog realities that chemical engineering disciplines bring to the table.
Alas...I digress.
The Framework For Energy Systems Analysis
When analyzing energy systems we know that it's important to take into consideration the following:
Minerals, metals, concrete, other materials, transportation, construction, operation, maintenance, safety, decommissioning, destruction, recycling, disposal, energy return on energy invested, energy payback period, financial payback period, and overall environmental effects.
You'd have to also take into consideration the dynamics of the energy grid itself and how it varies by geography.
You'd need to think through how generators:
a. synchronize voltage b. phase with the grid c. deal with energy storage
Armed with this frame work.... we know the following....
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.
Let's cut through the hype and look at what the numbers actually tell us about lithium propulsion for aircraft and boats. Spoiler alert: it's not pretty.
The Big Picture: Why This Matters
This visualization illustrates the interconnected phases of lithium propulsion system development and deployment, from raw material acquisition through end-of-life processing. The hexagonal nodes represent six critical stages: material acquisition (requiring 500,000 gallons of water per ton of extracted minerals), manufacturing, operations, grid integration, financial analysis (with lifecycle costs of $245-380/kWh), and end-of-life considerations. Arrows between components demonstrate the cyclical nature of sustainable system design, highlighting how decisions at each stage impact environmental footprint, operational efficiency, and economic viability throughout the entire lifecycle.
Look, I've analyzed every angle of lithium propulsion systems, and here's the unvarnished truth: it's a negative energy return on investment (EROI) across the entire U.S. grid. Anyone telling you otherwise is either misinformed or selling something—probably batteries.
The Energy Density Reality Check
Let's start with basic physics, because no amount of wishful thinking can overcome the laws of thermodynamics:
This isn't just an academic exercise. When MIT Technology Review points out that jet fuel packs 60 times more energy per kilogram than the best lithium batteries, that's not a minor engineering hurdle—it's a fundamental physical limitation.
As The Society of Automotive Engineers puts it in their latest technical assessment: electric propulsion systems drag around 1.7-2.3× the weight for the same range. That's dead weight that consumes more energy just to move itself.
The Hidden Energy Debt
Here's something the glossy brochures never tell you—before an electric boat or plane moves an inch, it's already deep in energy debt:
According to Gruber et al. (2021), a single ton of lithium extraction guzzles about 500,000 gallons of water. That's roughly the same as 30 average American households use in a year—just to extract enough lithium for a handful of large marine battery packs.
And we haven't even started manufacturing yet! The International Energy Agency documents that producing battery-grade lithium compounds demands 50-70 kWh of energy input per kilogram. That's enough electricity to power the average American home for 2-3 days... per kilogram of processed lithium.
The Grid Connection Mess
Electric vehicle enthusiasts love to talk about plugging in, but they conveniently ignore the grid reality:
Here's the uncomfortable truth from EPA's eGRID database: the carbon intensity of our electrical grid varies by a factor of 4× depending on where you are. In coal-heavy regions pushing 840g CO₂e/kWh, your "clean" electric boat is often dirtier than a modern diesel.
The National Renewable Energy Laboratory has extensively documented that transmission losses average 5-8% across the U.S. grid—energy that simply vanishes before it ever reaches your charger. During extreme weather events (when you need reliable transportation most), these losses spike to 12-15%.
Show Me The Money (Or Lack Thereof)
The economics get even uglier when you look at the payback periods:
According to the Aerospace Technology Institute, electric aircraft require 2-3× longer to achieve financial payback compared to conventional aircraft. When you're looking at paying off your investment in year 15 of a 22-year lifespan, you're left with little time to actually generate profit.
And the cost per unit of delivered energy? Not even close:
The Journal of Transport Economics published a comprehensive analysis showing lithium propulsion systems cost $245-380/kWh of delivered propulsion energy versus just $75-110/kWh for conventional systems. That's a 3.3× cost difference that no business model can overcome.
Real-World Performance Nightmares
The performance gap gets even worse when you leave the perfect conditions of the lab:
Cold Regions Science and Technology documented that in cold weather (-10°C), electric propulsion systems lose a third of their range while conventional systems lose just 6%. Anyone operating in northern regions knows what this means: unreliable service and stranded assets.
And don't get me started on refueling:
Transportation Science research shows that even "fast charging" still takes 40 minutes to reach 80% capacity, compared to 7 minutes for a complete conventional refill. This directly translates to a 22% reduction in asset utilization—meaning electric fleets need to be significantly larger to provide the same service levels.
Let's Get Real: The Path Forward
Look, I'm not saying electric propulsion can never work for aviation and marine applications. I'm saying it doesn't work now, and it won't work until we see:
Battery energy density improve by at least 4-5× (which requires fundamental material science breakthroughs, not incremental improvements)
Grid carbon intensity decrease by 60-70% across all regions (not just the Pacific Northwest)
Fast charging technology that can actually deliver 100% capacity in under 15 minutes without cooking the batteries
According to Resources, Conservation & Recycling, end-of-life processing adds another $35-50/kWh in specialized handling costs—battery disposal isn't just an environmental challenge, it's an economic one.
Chemistry is Hard. Much harder than physics. Electric propulsion for aircraft and boats remains an economically unsustainable proposition that fails basic energy accounting. Anyone claiming profitability is either leaving out major parts of the lifecycle analysis or banking on massive subsidies to mask the fundamental problems.
Chemistry doesn't care about your investment prospectus, and thermodynamics can't be overruled by marketing. The numbers don't lie—lithium propulsion for aircraft and boats is some montauk VC pension hot potato bullshit that has no viable conspiracy to overcome its fundamental atomic limitations.
MIT Technology Review. (2024). "The Energy Density Wall: Why Batteries Still Can't Compete with Fossil Fuels." Spring 2024 Edition. https://www.technologyreview.com/energy
Society of Automotive Engineers. (2024). "Weight analysis of electric propulsion systems for aviation applications." SAE Technical Paper 2024-01-0873. https://www.sae.org/publications/technical-papers
Journal of Aircraft Design. (2023). "Volume and weight constraints in electric aircraft design." 42(3), 308-321. https://arc.aiaa.org/loi/ja
Energy Information Administration. (2024). "Annual Energy Outlook 2024 with projections to 2050." U.S. Department of Energy. https://www.eia.gov/outlooks/aeo/
VISUALIZATION 5: Payback Period vs. System Lifespan
Aerospace Technology Institute. (2023). "Certification Requirements for Electric Propulsion Systems." CAA Technical Publication TP-2023-E5. https://www.ati.org.uk/
