Electric Airplanes Feasibility

As others have noted, electric flights require a major breakthrough in the battery technology. Here are energy density numbers for gasoline, jet fuel, and lithium-ion batteries:Gas and jet fuel specific energy density ~= 45 MJ/kg;Lithium-ion specific energy density Even worse, a jet engine is much better at generating power. A modern high-bypass turbofan engine can generate 10 kW/kg whereas an electric motor is around 1 kW/kg.In short we need much bett

Battery powered long distance flight is unlikely because gasoline/kerosene has 5 times the weight energy density of lithium ion. Short haul flights may be viable. Hydrogen fuel cell planes even better because hydrogen has 3 times the weight energy density of jet fuel and 15 times lithium batteries.

Not an expert, just the result of a Google search:Fuel has roughly 100x better energy density than lithium-ion batteries(both in weight and in volume), and batteries improve pretty slowly. Before take-off , the weight of fuel is 25-47% of the aircraft's weight.And since the propulsive efficiency of a jet engine is relatively high(rough search gives 45%-80%) an electric engine doesn't buy much here.So this isn't really a question of money, but basic limits.

Are electric airplanes feasible in the foreseeable future?

I think I remember reading somewhere that electric planes would have a much lower energy density than liquid fuel, making its utility minimal. How does hydrogen-powered flight compare regarding energy density?

Simple counterargument: you can't make a large electric plane. The energy density of a battery is too low.

Planes can absolutely be electrified. We just need to find a more dense energy storage medium than Li-ion/Li-poly batteries. Lithium-air batteries have energy density comparable to gasoline, so they might work if we can figure out how to make them rechargeable. A fuel cell could potentially work as well.

Surely hydrogen makes more sense for electric airplanes?

Cars are not airplanes. Electric cars are much heavier but weight isn't a big problem on the road. That's why they work, and they're still catching up to traditional range expectations.With airplanes, you have to lift that weight using the same energy stored within. In that case, energy density is the absolute issue. Nothing else matters.There's no magical solution, a high-school physics class will teach you how to calculate the potential energy requirement to lift up a

I think electric airplanes are still the more probable future. My understanding of the current problem is that the weight to energy ratio in electric batteries is still too high for useful flights. But this ratio is improving year by year, and very soon we will be near the number where electric aircrafts will be competitive with fossil fuel ones on some types of flights.