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  • Geomagnetic field Effects of Space Weather
  • Electric Power(power grids) distribution on Geomagnetic Induced Currents(GICs)

Electric Power(power grids) distribution on Geomagnetic Induced Currents(GICs)

  • Geomagnetic induced currents in power transmission lines, particularly in susceptible areas such as the Northeastern United States, may result in large-area electric power blackouts. Large, expensive utility transformers could be permanently damaged. For utilities, any power interruptions due to solar storms will put pressure on the remaining grid. Solar flares usually originate from solar active regions also associated with sunspots. Geomagnetic effects from flares occur when the flare accelerates waves of material and radiation energy into interplanetary space away from the sun and toward the earth. This solar wind package travels the 93 million miles through space and can impact the earth's magnetic field. The earth's magnetic field then undergoes a period of fluctuations. These fluctuations can induce electric currents within conductive material on or near the earth's surface ? e.g., ocean salt water, mineral ore and soil, and long utility transmission lines in areas where the ground soil is rocky and highly resistive to current flow. These events are collectively known as geomagnetic disturbances. The delay time between the flare and disturbance arrival can be anywhere from one to four days. The variations can be measured by ground-based and satellite magnetometers, but lead time for loss prevention action is very short. In 1989, during the last solar cycle, geomagnetic disturbances damaged utility-owned lectrical equipment in Virginia and the eastern United States. Also, 6 million people were left in the dark by a March 13 blackout in the Hydro Quebec system. The U.S. system came close to experiencing a similar outage. Less severe solar storms impacted earth in 1989, 1991 and 1992. In 1998, a smaller solar storm was blamed for bringing down the Galaxy 4 satellite, halting news transmissions and electronic pagers (45 million) across North America for days.

- Solar Activity May Cause Problems for Utilities (Ron Beherns) -