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science & techanalysisThe Conversation

Blackout risks are rising – why neighboring power grids can’t just send extra electricity where it’s needed

the gist

The United States doesn't have one power grid but three big ones, the Eastern, Western and Texas (ERCOT) interconnections, with few transmission lines between them. When a storm in February 2021 shut down generation in Texas, the state could import only about 6% of its demand, and operators cut power to over 4.5 million customers in the largest deliberate shutoff in US history. Even where lines exist, they can be wrecked: Hurricane Ida in 2021 knocked out all eight lines into New Orleans. A proposed 320-mile Southern Spirit line linking Texas to Louisiana and Mississippi could have cut the 2021 losses by roughly 15%.

how it works

Electricity must be produced as it is used, and must flow along wires with limited capacity, so power cannot simply be rerouted to a distant blackout without a high-capacity path.

so what

Moving power needs physical wires that survive the same storm. Experts say the fix is more links between regions plus hardening existing corridors so they recover faster.

fun fact

Texas deliberately kept its grid separate largely to avoid federal regulation of its power market.