Only the Portable Biofuel Generator is weather proof. The regular Biofuel Generator will take storm damage. (It shows the Sheltered/Unsheltered indicator.
#Biofuel generators are despawning on Prometheus
icy haven
heavy pier
Those generators should be placed inside.
It even says so in the tooltip.
So yeah, they take storm damage and get destroyed.
That's how the game is designed to work.
Now you might not like it, but it's not a bug, in working as designed.
It doesn't really need rebalancing if you place them in a shelter.
Yes, they're expensive to make (relatively speaking; I'd argue an advanced battery or a solar panel is more expensive); but that's why you should read the tooltip stating it needs shelter.
I don't think the "time until it's completely destroyed" should be directly linked to the cost of an item.
By the way, the wind turbines don't take storm damage as such.
They spin faster during a storm, and that's what damages the turbines; but it's no direct storm damage (this was explained quite a while ago in the patch notes).
So you can't really compare the damage numbers from the wind turbines to the damage numbers from the generator.
sand lake
solar panel can take damage in Prometheus?