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zonavar68 How do you scale that up to full-size commercial or military transport aircraft?
The truth is, EV doesn't work on anything commercial, including commercial ocean vessels.
My field of expertise lies in the commercial nautical marine industry. The only time that an ocean vessel can be converted to EV from diesel is in the application of a luxury ocean yacht. This is because a vessel of this category does not normally carry cargo, which means it's gross weight essentially stays constant all the time, since after all, it's only a floating hotel for a dozen or more party animals.
Part of the cost per mile calculations for commercial cargo ships on the other hand, makes the assumption that when a ship leaves port in England full of diesel fuel for it's own engines and bound for the Orient, that by the time the vessel reaches it's half-way point in the journey, almost half of it's fuel load has been spent.
This means that from the half-way point to destination, the actual cost per mile to move the vessel decreases significantly because of the 50% reduction in fuel weight as the ship's fuel was being spent by it's own engines.
As the vessel completes 75% of it's journey, it's fuel load is now down to about 1/4 of it's original weight, which again means the cost per mile during the last quarter of the voyage is reduced significantly once again.
The bottom line is, the cost per mile calculation is based on an average of 1/2 a load of diesel fuel for the entire voyage, because 1/2 a load is what the "average" is between full tanks and empty tanks. That of course, you knew.
With a fully electric cargo ship utilizing EV technology, the weight of the fuel load (the battery) is identical at the end of the voyage from what it started out as in the beginning of the voyage, simply because the weight of the battery does NOT decrease as the EV charge is diminished from full charge to zero charge.
The cost per mile therefore, must be based on a full load of fuel weight FROM departure point all the way TO the destination point, which means the cost remains high and never decreases from point A to point B, simply because nothing tangible is being spent by the EV motors. Electric charge is not tangible because it cannot be seen nor felt, which means the battery weight does not reduce as the charge is depleted, unlike diesel fuel tanks which slowly become empty and therefore the weight of diesel is no longer carried.
The weight of a gallon of diesel fuel is about 8.5 pounds per Imperial gallon.
I've over-simplified this calculation for the sake of your question, though I already know that you know the obvious to the points I've made.
Military transport aircraft have the same issue. A transport aircraft has a maximum take-off weight (MTOW) that is far greater than it's maximum landing weight (MLW). This means that a transport category aircraft can takeoff overweight, but it cannot land overweight without dumping fuel overboard.
When a jet fuel powered transport aircraft takes off fully loaded, it's gross weight diminishes as it's journey progresses, thereby making it easier for the aircraft to climb to higher altitudes where the cost per mile is significantly reduced do to the rarified air, hence less drag imposed upon the airframe, hence cheaper operating cost and longer range resulting.
If that transport aircraft were to be fitting with EV batteries, the gross weight of the aircraft would never change because no solid fuel is being spent and therefore, the aircraft does not get lighter as the journey continues.
This means the aircraft would end up having a much SHORTER range capability than a jet-fuel based aircraft because it would not be getting lighter as the journey progressed and would therefore land at the same gross weight it took off at.
EV therefore, only works in pleasure craft where the efficiency of the craft in question is not based on the gross weight of the unit reducing as the journey progresses.
