Lightning Dissipators

Question

I have heard about many lightning protection strategies in the shack, but nobody mentioned the lightning dissipator.

The lightning dissipator consists of many small spikes and prevents a strike by slowly discharging through each little spike.

This would seem to be much more advantegous to a radio amateur because it would try to prevent lightning, not advocate, and even better, it will slowly discharge the to-be-strike so lightning won't get anywhere else.

Is price an issue? I don't think so, becuase this seems like a fairly cheap solution just consisting of many metal spikes bonded to ground.

So are any amateurs using dissipators? Are they known to work? Should I consider for my shack?

Answer 1

Seems mythical. For example, this article discusses in a fair amount of detail why this doesn't work for sailboats. Land-based antennas face the same issues.

Some people believe that by constantly discharging the charge build-up on an object, the magnitude of the charge imbalance can be controlled and kept to a level where a lightning strike will not occur. Continuous dissipation of static charge potentials is used in every electronics laboratory that works with sensitive integrated circuits and transistors. The workers wear wristbands of conductive material that are connected to the room’s electrical ground. Charges bleed off before they reach levels that might destroy the electronics.

Unfortunately, what works in a laboratory, with very modest static charge quantities, does not work in nature. Let’s look at the facts that govern the charge dissipation approach to undoing what Thor wants to do—blast us with a lightning bolt

Answer 2

These alternative air termination systems are a triumph of marketing over physics.

I'll quote what I can easily find on the net, you will find a lot more with a bit of digging.

These statements are quite reserved, but the meaning is clear - there is no evidence that there is any system that works to dissipate, preferentially attract or repel lightning. The only proven solution is an air terminal on every exposed corner, and a downconductor system to carry the strike to ground.

STATEMENT OF CIGRE TASK FORCE 33.01.03 “LIGHTNING INTERCEPTION”

• The components of the Task Force during the meeting held in Milano on May 18th 1995, have examined the problem related with the use of non conventional lightning air terminals (e.g. Early Streamer Emission).

• From the discussion it arise that up to now there is neither sufficient theoretical analysis, nor substantial field data which support conclusive improvement in interception efficiency of these kinds of devices with respect to the conventional ones (metallic air terminals).

• Main technical reasons

– 1 – Even if a streamer from a non conventional active terminal can be launched at an earlier time than a streamer from a conventional air terminal, once launched, it will require the same conditions of field strength to propagate as for a leader from a conventional air terminal.

– 2 - The assumed constant velocity of 106 m/s for upward leader propagation is in contrast with the field records which show an initial channel speed of about 0.04 to 0.2 106 m/s and it increases as the gap between the upward and downward leaders diminishes.

CIGRE 95 SC 33 (WG 01) 17 IWD, 24th May 1995

• The members of the Working Group during the meeting held in South Africa on 23rd and 24th of May 1995, have examined the problems related to the use of non-conventional lightning air terminals (e.g. Early Streamer Emission, ESE, terminals).

• From the discussion it was concluded that up to now there is neither sufficient theoretical analysis nor substantial field data which support claims of significant improvement in interception efficiency of these kinds of devices, with respect to the conventional ones (metallic air terminals). Furthermore, the theoretical basis for the Early Streamer Emission technology appears technically incorrect for the following reasons:

– 1 - Even if a streamer from a non-conventional terminal can be initiated at an earlier time than a streamer from a conventional air terminal, once initiated it will require the same field strength to propagate as a leader from a conventional terminal.

– 2 - The assumed constant velocity of 106 m/s for the upward leader propagation is in contradiction with the available data for both natural lightning and long laboratory sparks which show an average velocity of one order of magnitude lower.

• Therefore the early initiation of streamers cannot be translated into an increased length of the ESE terminal as compared with the conventional one.

• In conclusion, at this time, any use of such non-conventional lightning protection technology cannot be supported by CIGRE WG 33.01 “Lightning”.

Answer 3

It is my opinion and experience that lightning DOES NOT CARE what you put in its way. It destroys EVERYTHING that tries to conduct the HUGE amount of energy in the lighting. It can be diverted to a lower resistance path, but it STILL has too much energy to contain or control it without MASSIVE equipment made just for that purpose. (a lightning lab for example).