Very good job Mike , knowledge of what lightning can do even in today technology , still need the best protection Thank Mike I like any good infromation about lightning your training book give good knowledge how lightning works and people need to know about lightning in your book. I was so surprize to learn lighting comes from the sky leaders , and attraction from the ground streamer and lighting don't care if it see wood or metal it will hits the hightest one in the area and the sky give about 8,000 volts just before it hit a area . John Hall

My guess, and it's only that, is that this station lightning rod density was to thin. Proper protection would require no more than a 20 foot distance between rods. As I've said, lightning is opportunistic. It will strike the highest conductive point in a given area (conductive, because the ionization path is usually necessary). A single rod does not protect the whole darn city. At our campus the physics building alone has 30 rods bonded with 00 bare copper-for a single building. As a side bar, scientists and engineers still fight over whether the rods should be pointed or blunt. americans like Franklin's pointed rods-Europeans use the blunted. I don't think it makes any difference. Blunted is better for birds.Many die stabbing themselves on the pointed rods.

Yes, Lightning will strike wood. It strikes trees thousands of times a day, but first the tree is high and secondly a tree full of sap - though it may be considered an insulator- has a break down voltage of far less than 10,000,000 volts. However, I can protect that tree with a metal lightning rod. Because the leader (ionization path) will prefer it. All insulators have some break down voltage. When that's exceeded the insulator becomes a very good conductor. Don't cut a 13, 000 volt cable with your tape covered dikes. And if you make lightning rods from wood or an insulator they won't protect as well as those that are conductive. However, If enough people start to believe lightning rods made from wood are just as good as metal, I'm going to start selling them. i'll be the only supplier-I'll have a monopoly.

I can't tell you how many projects I've worked on that, when the subject of lightning protection (LP) came up, it was dismissed as not required by code, and an unnecessary expense. NFPA has a LP risk calculation method that will help the EE or EC argue the point, but even with a high risk result, they don't "buy" it. It is wise for the EE or EC to contact (or have the owner contact) the property's fire insurance co. for a possible premium reduction for a Master Label LP system.

Is it just me or does it sound like the public is going to pay for this. If so then I think the old adage may apply,

Piss Poor planing on your part does not constitute an emergrncy on mine.

Why should the public have to pay for this. It is just like the oil industry making billions of dollars in profit,yet fuel prices still go up. Just a thought.

As an example of what lightning can do:

Lightning struck a 180 ft. structure, passed through the metal roof, into an MCC at the top level, blew the mastic (tar) out of one of the mounting screw recesses on a size 4 starter, bridged the gap to one of the load side contacts and traveled to the basement, taking out the motor connected to it. I suppose the direction of travel for the discharge current, was from the basement upwards, based on the "tar" incident. This structure is constructed of steel "I" beams, with a sheet metal skin. This incident made me wonder why the designer of this system had chosen to place the motor starter at the top level instead of near the motor and routing the control wiring to the top level.

This is the best link on lightning protection I know of.

http://www.lightningsafety.com/nlsi_lhm/conventionalLPT.pdf

it explains in detail the mistakes made with lightning rods (air terminals as they are technically known)

This is a sensational news story, but without technical detail. What exactly was damaged? Did it involve the generator windings? Were the boilers damaged? Switchgear? There is no opportunity to learn here. There is no mention of what is being done to prevent or at least alleviate this damage in the future. Just another news story.....