This kind of information has been available via open data for ages, and it isn't exactly hard for a foreign power with boots on the ground to figure out either.
With this kind of large-scale infrastructure it just isn't viable to rely on security through obscurity. If you want to protect against failure, invest in redundancy.
I didn’t mean this substation existing. I know that’s obviously not a secret. The fact taking it out takes out the entire main airport for at least an entire day is a different matter. Do you really think they’d have been fine with you announcing that to the world yesterday?
Don’t forget the BT Tower existing was technically classified under the official secrets act, even though it was extremely obviously there for everyone to see including on maps.
With this kind of large-scale infrastructure it just isn't viable to rely on security through obscurity. If you want to protect against failure, invest in redundancy.