Under some circumstances, a severe solar storm could create disturbances in Earth’s magnetic field that lead to extensive power outages.
We looked at some technologies intended to protect the U.S. electrical grid from possible effects of these disturbances. Technologies being tested include:
systems that block currents from geomagnetic disturbances
power transformers designed to be more resistant to such currents
The government has taken some steps to mitigate risks, but questions remain regarding the likelihood and intensity of damage from geomagnetic disturbances.
Source: CRITICAL INFRASTRUCTURE PROTECTION: Protecting the Electric Grid from Geomagnetic Disturbances