this post was submitted on 29 Jun 2025
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[–] Scubus@sh.itjust.works 15 points 2 days ago* (last edited 2 days ago) (24 children)

Havent read the article yet, but I recall reading that with modern battery architecture electric planes were physically impossible. Is this plane not using lithium ion, or was I mistaken? It wasnt an issue of the tech not being ready yet, moreso that lithium ion simply could not achieve an energy density to weight ratio that was needed.

Edit: the article does not say.

Second edit: how far off are we from either not having power storage or only minimal power storage and then we just beam energy to the plane?

[–] Mohamed@lemmy.ca 12 points 2 days ago* (last edited 2 days ago) (4 children)

I think it is more specifically electric planes as large as commercial airline passenger planes are impossible. It has a lot to do with battery mass to energy content ratio. Kerosine is about 46.4 MJ (megajoules) per kilogram. Lithium-air batteries, for example, only have about 6.12 MJ/kg.

So, that means you need 7 times as much battery (in mass) to have the same energy content of kerosine fuel. Naively, we can maybe say that means electric planes only have 1/6 of the range of an equivalent kerosine plane.[^]

Interestingly, lithium-air batteries theoretically have the largest possible energy density for any battery at 40.1 MJ/kg.

^ The calculations are really basic and probably only slightly reflect reality (since there are many other important factors. For example, Hydrogen has a lot more energy per kilogram than kerosine, but because it is much less dense, it has much less energy per m^3 than kerosine. This has made hydrogen gas very impractical for either internal-combustion engines, or planes), but I think it gives an idea of what the problem is.

[–] nBodyProblem@lemmy.world 4 points 1 day ago (3 children)

There are a lot of other factors. For example, electric motors with propellers are far more efficient than turbofans

A propeller driven airplane will also be substantially slower than a turbofan one, allowing for unswept wings and better aerodynamic efficiency

In reality, battery powered passenger planes aren’t impossible but they will definitely have a shorter range and slower speed. They are realistically only suited for regional routes.

[–] Obi@sopuli.xyz 1 points 1 day ago (2 children)

Perfect is the enemy of good. There are so many people at least here in Europe that fly easy-jet/ryanair 1h to 2h flights, these could all still work with propeller planes. But frankly I'm just wondering why I can't get subsidized trains that would be actually affordable. Right now it remains cheaper to drive all alone in my car than get an Eurostar ticket unless I planned it months in advance (spoilers: I can't plan months in advance most of the time with my work).

[–] nBodyProblem@lemmy.world 1 points 22 hours ago

Agreed. A plane that can do 200ish knots for a few hours could hit a nice sweet spot for a lot of routes

[–] bent@feddit.dk 1 points 1 day ago

This would be perfect for Norway. Oslo-Trondheim and Oslo-Bergen is consistently among the most trafficked air routes in Europe and the train ride is 7-8 hours. I love trains and use them whenever I can and even though I believe we should get better train infrastructure between the largest cities I also concede the fact that beyond those it's just not practical with trains all the way up north or out to the small coast communities.

Electric planes with a few hundred kilometers reach would suite our domestic travel juuust fine. I might even have started my European interrail trip with a short flight to Oslo or Copenhagen if electric planes where doable and reasonable (in terms of both cost and emissions).

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