Could a flying creature get it's electrical energy from storms?

Question

I've got some draconic creatures that can store and discharge/manipulate electrical energy. (think flying electric eels.) Would it be at all plausible, given the right conditions, for them to somehow get their energy from electrical storms? (I realize there are more efficient and far less dangerous ways to get the energy they'd need, like caloric intake, but well, it's a cool picture and I want to see if I can make it work in some way.)

Note:

These creatures are at least semi aquatic, so they wouldn't be throwing lightning bolts from the sky or anything.

I'd like their energy to come from an external source.

The energy they'd collect is purely for electrical powers, assume that all basic life functions are taken care of by food intake.

Lets also assume that they could somehow avoid being hit by lightning, either by sensing and avoiding or some kind of electrical manipulation protection (or whatever other hand waving is necessary)

Answer 1

Yes, but they would need to be inconveniently large/long.

There is most definitely electrical energy to be had in storms, just look at lightning.
The available voltage gradients are quite sufficient, up to 300V per cm.
Unfortunately, this electrical energy is present in the form of static electricity, and thus the charge density per volume is very, very, very low thus current that can be generated by connecting these voltages is equally very,very low.

To gather enough energy to matter, one has to involve truly gargantuan volumes of air. Lightning does this by utilizing volumes as "small" as 500m cubed. That's 125 million cubic meters, or 160 million kg. But usually the feed area of lightning is 2 to 3 magnitudes larger than this, and affecting the static charge in a few billion to trillion kg of air.

So your creature needs to connect to a similarly large volume of air, which is impractical, or needs to connect to smaller volumes of air that are much further apart, and thus at greater voltage relative to each other. Possibly a loooong filament dragging through the air behind it? (hundreds of meters)

If your creature can efficiently harvest static from the air, it might not even need storms for power, as long as it is patient.
Even in still air there is a voltage gradient above the ground.
While stormcloud generate static by interaction with falling droplets of water, and thus present a relatively dense source of charge that is rapidly replenished, there is a natural voltage gradient in air close (few hundred meters) above the ground, with a gradient of about 100V/m. This field just replenishes much slower than in a storm, making stationary "free air power harvesters" nothing more than a scientific curiosity.

But with a mobile creature moving over a large area collecting as it goes, it might be viable.