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Modern solar panels are about 20-25% efficient. Putting it in a battery and using it to drive a car is about 80-90% efficient. Both the battery and motor lose some energy. If you multiply that, you get to about 16-22% efficient (starting with sunlight). And solar panels and batteries are still improving. Perovskite and other multi layer panel technologies provide a path to 35-40% panel efficiency.

Getting a similar efficiency generating some fuel that you then burn at 20% efficiency in a combustion engine results in a net efficiency of about 5%. That might improve on the fuel generation side but electricity generation would improve in a similar way and it would not be as efficient as that (thermodynamic laws and all that). It's basically not going to get much better than being between 4-8x less efficient than battery electric.

BEVs are winning on price and cost for that reason. Batteries are getting dirt cheap (50-60$/kwh). Solar and wind energy basically have no marginal cost. Driving 500K miles at 20 gallons/mile costs 75K$ at 3$/gallon for 25K gallons of fuel. 500K miles is a realistic life expectancy for modern battery electric drive trains. Good luck with that with an ICE car. Grid electricity isn't free but it won't cost you 75K. And honestly, you're going to be spending more than that on fuel in most parts of the world. And there's maintenance, parts, oil (engines use a lot of that too), etc. Bottom line: you could buy a new EV for 30-40K, and use the remaining savings for maintenance, tires, etc. All on the money that you aren't spending on fuel. Even a free ICE car would be a bad deal compared to that. You'd lose more money on just the fuel than you save on the car.

Now are efuels going to be cheaper or more expensive than regular fuel? It's a rhetorical question. We all know the answer (no way in hell). Hydrogen, bio fuels, efuels, etc. don't really stand any chance economically. None whatsoever. This is just greenwashing noise. None of that stuff is going to scale or matter. Some of the technology might matter for other purposes though. Hydrogen is super useful for lots of things and providing chemicals that we currently produce from oils synthetically could be valuable too.






> 20 gallons/mile

I did a double take here, I believe you mean miles per gallon?

> We all know the answer (no way in hell). Hydrogen, bio fuels, efuels, etc. don't really stand any chance economically. None whatsoever. This is just greenwashing noise. None of that stuff is going to scale or matter.

Disagree, you seem to only be considering cars. All of these things are just different forms of energy storage and they are useful if battery technology doesn’t have multiple orders of magnitude of improvement left in it.

There are numerous high impact use cases where you need more density, faster energy transfer, and completely different weight profiles than batteries.


obviously, nice catch



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