I don't think so...
Darkness has no substance; it isn't a thing, but an absence of a thing.
There would be nothing to use for energy.

Darkness will act like a vacuum sucking air from the high temperature light areas, so in theory ..yes!

Isn't that what "dark energy" is?

I like to think of the void, or darkness as you call it, as nothing ! I then bend my mind onto the q of what is nothing ?
If I was to propose that equilibrium of energy gives a state of nothing due to lack of potential difference what would you say ! :detective:

What's this "q" you're talking about?

I would say that a state of equilibrium is different than a state of nothingness.
Equilibrium has two things that are perfectly balanced against each other - nothingness has zero things, period.

"Darkness will act like a vacuum sucking air from the high temperature light areas, so in theory ..yes!"

I think we would technically call that wind energy. Light and the absence of light would be used to create rooms with differing temperatures, and then we would harness the energy of the motion of air caused by the temp. difference. In that scenario we are using light as the main source of energy and then harnessing the wind it creates.
That's not harnessing energy from darkness.

I don't think it is impossible. We have sources that give light, which will give out light in darkness, but no source of darkness. I think to make energy from darkness, we need a way to regulate the darkness, when its dark, or maybe a source of darkness when there is light.

I guess I'm way late on this but-
Darkness is the absence of light.
light is made up of photons.
There aren't "anti" photons in darkness(that we can observe), so there's no particle to harness to create energy from.

Dark energy is not made up of darkness. It's called Dark energy and Dark matter because its purely theoretical, since its unobservable.
just like darkness is un-observable.
You technically can't observe or measure darkness, you can only measure the amount of light is there. Darkness has no particle so you can't measure it.

Why would you want energy from darkness
Curious