Insurance Claims Reveal Hidden Electronic Damage From Geomagnetic Storms

KentuckyFC writes: On 13 March 1989, a powerful geomagnetic storm severely disrupted the Hydro-Québec high-voltage grid triggering numerous circuit breakers and blacking out much of eastern Canada and the northeastern U.S. Since then, Earth has been hit by numerous solar maelstroms without such large-scale disruption. But the smaller-scale effect of these storms on low voltage transmissions lines, and the equipment connected to them, has been unknown. Until now. Researchers from the Lockheed Martin Solar and Astrophysics Laboratory have analyzed insurance claims for damage to industrial electrical equipment between 2000 and 2010 and found a clear correlation with geomagnetic activity. They say that the number of claims increases by up to 20 per cent on the days of highest geomagnetic activity. On this basis, they calculate that the economic impact of geomagnetic damage must amount to several billion dollars per year. That raises the question of the impact these storms have on household electronic equipment, such as computers, smartphones and tablets, and whether domestic insurance claims might throw some light on the issue.

Tablets?

[Anonymous Coward]

Geomagnetic storms induce very slow changes (over minutes to several hours) in the magnetic field, hence the induced voltage in electrical circuits is very small unless you have very large loops in the circuits (large, as in miles). A tablet is not going pick up any significant voltage, and would have more induced electric currents by setting on top of an extension cord, or attaching a cover that uses a permanent magnet... or walking by a fridge. There is a small chance maybe something happens if it was plugged in, but today most electronics use a switching power supply that can hand a decent range of voltages, and the mains voltage would have to go way out of spec, and then most likely only damage the power supply. And a lot of those power supplies can work at dual voltage, so if you are on a 110 service, you would need it to spike over 220 V to do damage.

Time to apply science

[Technician]

Time to apply science to the problem. What is known, what values are involved, and what breaks down.

Long distance transmission lines have two problems when there is a relatively high atmospheric current. They are long conductors feeding transformers that are not designed to shunt large components of DC resulting in core saturation and high current. This is measurable. The first effect noticed was by the railroad when telegraph relays activated and sometimes burned out.

The voltage induced current has two components. 1 Some current was due to the current directly into the long wire. 2 Some current was due to ground potential changing due to high current in the ground.

How to protect? For ground potential issues, simple pairs of wires provide high common mode rejection. This is common with telephone circuits as protection from induced hum and noise from a noisy electrical environment. Overvoltage protection in the form of lightning arresters is the second protection. Most phone loops are relatively short reducing the ground voltage gradient problem to non existant levels. Long distance hops are by Microwave Relay or Fiber Optic, both providing protection from ground gradients and long pick up paths.

Shrink the scale to inside a home by comparison. All internal house wireing is orders of magnatude shorter than transmission lines, CATV, and phone lines. Small DC capible antennas result in very low current if exposed. The home is generally protected by gutters on the eves, mildly conductive building materials such as wood, brick, etc that are not insulated to very low leakage at high voltages such as the insulatin on transmission lines. Net result is the very small currents are shunted by the building itself. Go up on the roof during a geo storm and see if you have any static electricity issues. Probably not.

For homeowners, this is a non issue due to the lack of an effective gathering surface properly insulated to collect enough current to cause any damage. The collector is too small and the leakage path to ground is too high.