A historic electric airplane flight landed at JFK with passengers, marking a milestone as Beta Technologies demonstrates the practicality and efficiency of electric air travel.
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?
It’s absolutely not impossible. Airplanes are more efficient than drones, and efficiency grows with scale. Drones fly. Of course an airplane can do the same.
The problem is one of speed and range. The best form of propulsion we have for electric airplanes is the propeller, which has a lower top speed potential than a turbofan. The energy density of batteries is also lower.
Realistically, an electric airplane will have reduced range and speed compared to a modern jet.
Any idea why they went with an open prop vs a ducted fan?
edit: the motors are 600mm diameter, so not easy to install in the duct is my guess. It’s impossible to package an inboard configuration on such small airframes.
I can’t comment for their engineering team, but usually open props are more efficient because any reasonably sized duct constrains prop diameter. Increasing prop diameter is the best way to improve efficiency. Ducting a very large diameter prop comes with a large structural and weight penalty.
Generally speaking, the only time ducts buy their way on is when they are also needed for bystander protection.
Another issue is batteries don’t change (significantly) in mass during flight. Most airliners have greater takeoff weight than landing weight, because after flying a jet for a few hours you’re going to burn many tons of fuel. Batteries don’t do that, so you’d have to have an airplane capable of landing at it’s MTOW.
Also planes tend to increase their cruising altitude as weight decreases, it’s more efficient due to the lower air resistance. Electric motors would be more efficient across a wider range of conditions than turbo fans though.
That’s all moot though, because you must don’t have the energy density for long haul flights in batteries. They’re trying to make air taxis happen again. They were talking up air taxis before 9/11, and they never really happened. And back then they were talking about using existing aircraft driven by conventional gasoline or jet fuel. Now we’re talking about new airframes with battery electric power.
“Air Taxi” operations looked more like, say you’re going golfing in Pinehurst, NC. If you take an airline, you’re probably going to get a flight to RDU, rent a car at the airport, drive an hour down US-1. Or if you’re enough of a high roller, the Pinehurst Hotel will have sent a limousine an hour up US-1. Either way you’re talking driving boomer golf shorts royalty through Sanford and Tramway, and those towns just aren’t very Wall Street Journal.
Instead, load them in a Cessna Centurion and make a ~20 minute flight to the Moore County Airport, which depending on traffic around the circle. Something like 12 golf courses to include Pinehurst #2 are within a 10 minute drive. The 36 hole Country Club of Whispering Pines is just behind the airport, the 10th hole and 11th tee of the Pines course is across the street from runway 23’s threshold.
North Carolina has over a hundred public municipal airports, the vast majority see no regular airline traffic at all, and not everyone traveling to North Carolina is going to Raleigh, Greensboro, Charlotte, Asheville, Fayetteville or Wilmington. Those are the only places Boeings or Airbuses ever go.
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.
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.
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).
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).
My dad was an apiarist, bee keeper, and educator.
One of may favourite bee anatomy facts is that the spots on their hind legs that collects pollen…is called Pollen Pants. Love it. Fucking amazing.
Assuming $8 for energy, let’s say $0.12/kWh you’re looking at 64kWH. That’s like 1kWh/mi, which is pretty fucking bad. There’s no way they’re scaling this up, because the battery has to weigh at least 1 Ton. So to double the distance you’d need to initially add double the battery, but that’s equivalent of adding 8 fat fucking Americanos to the payload, there by reducing the distance you can travel.
Meanwhile a Cessna Jet gets like 27/mi per gallon. So 2.5 gallons of fuel gets the same travel distance, and that only weighs like 20lbs.
Also, haven’t looked lately, but last I remembered, jet fuel was like $11/gal.
Yeah now add more batteries to double the flight range. 8lbs per gallon is 16lbs, versus like 2,400lbs of battery. The inefficiency goes through the roof.
It’s a problem of range. Jet planes have the advantage that they get lighter as the flight goes on, so for shorter flights, the battery issue is not as big of a problem. It’s not a physical impossibility to achieve flight with lithium ion, it’s a question of how far.
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?
It’s absolutely not impossible. Airplanes are more efficient than drones, and efficiency grows with scale. Drones fly. Of course an airplane can do the same.
The problem is one of speed and range. The best form of propulsion we have for electric airplanes is the propeller, which has a lower top speed potential than a turbofan. The energy density of batteries is also lower.
Realistically, an electric airplane will have reduced range and speed compared to a modern jet.
Any idea why they went with an open prop vs a ducted fan?
edit: the motors are 600mm diameter, so not easy to install in the duct is my guess. It’s impossible to package an inboard configuration on such small airframes.
I can’t comment for their engineering team, but usually open props are more efficient because any reasonably sized duct constrains prop diameter. Increasing prop diameter is the best way to improve efficiency. Ducting a very large diameter prop comes with a large structural and weight penalty.
Generally speaking, the only time ducts buy their way on is when they are also needed for bystander protection.
Another issue is batteries don’t change (significantly) in mass during flight. Most airliners have greater takeoff weight than landing weight, because after flying a jet for a few hours you’re going to burn many tons of fuel. Batteries don’t do that, so you’d have to have an airplane capable of landing at it’s MTOW.
Also planes tend to increase their cruising altitude as weight decreases, it’s more efficient due to the lower air resistance. Electric motors would be more efficient across a wider range of conditions than turbo fans though.
That’s all moot though, because you must don’t have the energy density for long haul flights in batteries. They’re trying to make air taxis happen again. They were talking up air taxis before 9/11, and they never really happened. And back then they were talking about using existing aircraft driven by conventional gasoline or jet fuel. Now we’re talking about new airframes with battery electric power.
Could you imagine the fucking noise? Air taxis should never happen.
“Air Taxi” operations looked more like, say you’re going golfing in Pinehurst, NC. If you take an airline, you’re probably going to get a flight to RDU, rent a car at the airport, drive an hour down US-1. Or if you’re enough of a high roller, the Pinehurst Hotel will have sent a limousine an hour up US-1. Either way you’re talking driving boomer golf shorts royalty through Sanford and Tramway, and those towns just aren’t very Wall Street Journal.
Instead, load them in a Cessna Centurion and make a ~20 minute flight to the Moore County Airport, which depending on traffic around the circle. Something like 12 golf courses to include Pinehurst #2 are within a 10 minute drive. The 36 hole Country Club of Whispering Pines is just behind the airport, the 10th hole and 11th tee of the Pines course is across the street from runway 23’s threshold.
North Carolina has over a hundred public municipal airports, the vast majority see no regular airline traffic at all, and not everyone traveling to North Carolina is going to Raleigh, Greensboro, Charlotte, Asheville, Fayetteville or Wilmington. Those are the only places Boeings or Airbuses ever go.
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.
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.
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).
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).
Agreed. A plane that can do 200ish knots for a few hours could hit a nice sweet spot for a lot of routes
Something something bumblebees.
My dad was an apiarist, bee keeper, and educator.
One of may favourite bee anatomy facts is that the spots on their hind legs that collects pollen…is called Pollen Pants. Love it. Fucking amazing.
Assuming $8 for energy, let’s say $0.12/kWh you’re looking at 64kWH. That’s like 1kWh/mi, which is pretty fucking bad. There’s no way they’re scaling this up, because the battery has to weigh at least 1 Ton. So to double the distance you’d need to initially add double the battery, but that’s equivalent of adding 8 fat fucking Americanos to the payload, there by reducing the distance you can travel.
Meanwhile a Cessna Jet gets like 27/mi per gallon. So 2.5 gallons of fuel gets the same travel distance, and that only weighs like 20lbs.
Also, haven’t looked lately, but last I remembered, jet fuel was like $11/gal.
Where do you pay .12/KWH?
Ontario, Canada, iirc the average 24hr rate on time of day use is 12¢/kWh…in CA cents.
Charge at night and I think you can get to a little under 9¢
Right? I pay more than three times that at 0.38€/kWh or 0.45$/kWh. Must be somewhere with tons of hydro.
Ontario is mostly nuclear with some hydro and lastly some fossil sprinkled in. But I suspect a lot also comes from 100% hydro Quebec.
Lmao, I pay $0.0608 sept-June and $0.12 the other months.
Fucking Idaho.
$0.12/kWh is pretty cheap tbh.
I was making the maths with $0,40/kWh which is expensive but can be seen is some countries, and that gives around 20kWh/100km.
It is impressive that a plane does not consume more power than a car (based on false maths ofc)
Yeah now add more batteries to double the flight range. 8lbs per gallon is 16lbs, versus like 2,400lbs of battery. The inefficiency goes through the roof.
It’s a problem of range. Jet planes have the advantage that they get lighter as the flight goes on, so for shorter flights, the battery issue is not as big of a problem. It’s not a physical impossibility to achieve flight with lithium ion, it’s a question of how far.