I think you've been hoaxed. About half way through it, there is a shot of fuel, hence the black smoke from the ensuing fireball. Right near the end, you can clearly see a shadow of a person reaching over the model, presumably to extinguish the fuel introduced halfway through the cilp. Also, why is there laughter from an audience right before the bogus "calling all available units" type radio call.
There is no way this is a real substation blowing, unless it weere situated on top of a 5000 gallon fuel storage tank and 800' tall men are walking around.
You're nuts. The video is from this site, where there are other videos of fun stuff. Given the nature of the site and its contents, I see no reason to believe its a hoax. I think its you who are imagining things. The "shot of fuel" comes from the ruptured transformer, which are oil-filled. Prior to the big explosion, you can clearly see the vaporized oil spewing out. Check out the site and the description of the video. As for the "shadow of a person", I have watched this video dozens of times, and watched it four more times just now to try and find what you're referring to. In all honesty, I can't find anything in the clip that even faintly resembles a "shadow of a person". Finally, the "laughter from an audience", to anyone who watches the video, is clearly the screaming of frightened female onlookers.
While there certainly are hoaxes on the 'net, not every video is.