“Why Electric Planes are Inevitably Coming”

https://youtu.be/aH4b3sAs-l8

tldr: They’re already being deployed in some shorthaul routes.

There are electric planes out there, but they're pretty small. You're not likely going to see any electric 747s anytime soon, if ever.

"A battery's efficiency, or ability to hold power, is measured in specific energy. Right now, even the best batteries have a specific energy of only 250 watt-hours per kilogram, but we have to get closer to 800 to really start flying, and that is still nothing compared to jet fuel's specific energy, which is nearly 12,000 watt-hours per kilogram."

"So if you want to add more power to a plane, you need to get a bigger battery, and to get that plane airborne despite the weight, you'll need even bigger battery that's more powerful, but that means more weight. And then you'll need an even bigger battery to offset that weight."

https://www.businessinsider.com/electric-planes-future-of-av...

Not with Lithium-Ion tech, no. But aluminum-air batteries provide an order of magnitude higher densities of energy(~1300Wh/kg), and should be able to power a large-ish plane. The main problem being of course that aluminum air batteries are not rechargable, but all you'd need to do is swap the spent aluminium rods at the airport and replace them with fresh ones - then use renewable energy nearby to melt and reform the aluminium rods to be used again.

https://en.wikipedia.org/wiki/Aluminium%E2%80%93air_battery

Interesting. I'm surprised I didn't hear that solution mentioned in Bill Gates "How to Avoid a Climate Disaster" book.

He basically made the same battery weight argument and was pushing for alternative biofuels for planes, if I remember correctly. And that was just published earlier this year, and seemed pretty comprehensive about discussing all possible solutions, at least as far as I could tell.

Maybe just because it's (presumably) nowhere near the point where it could be feasible for commercial passenger planes?

Mostly fuel energy density vs battery energy density.

You can use some biofuels (limonene) as a near-direct substitute for jet fuel though. I think maybe you need to change a few o-rings but the vapor pressure, combustion point, etc are all there and it's been demonstrated in Australia.

If by electric you mean batteries, it’s only realistic for very short flights.

For longer flights there are other more realistic alternatives with no net emissions, which are mainly hydrogen (made from electrolysis) and biofuels (made using carbon already present in the air).

At the range where electric planes are possible, they compete heavily with trains (which have less overhead for boarding and arrive closer to city center, which saves time).

Basically, imagine you have an electric plane with a range of 500 miles and travels at 250mph, and a train that travels at 125mph.

For the 500 mile trip, it's 2 vs 4 hours, but the train ride is generally going to be a better experience, and you'll arrive more rested and closer to your destination.

For a location like Europe, where high-speed rail is fairly developed, it's a hard sell to switch to electric planes in this case, IMO.