When extreme heat hits, people turn to AC, but what if the grid fails? From France to the US, heat waves are pushing power systems to the limit, raising blackout risks and energy prices when electricity is needed most.

During extreme heat waves, power grids are more vulnerable to outages. Experts and utilities said there are many ways people can reduce the energy strain.

A brutal heatwave strains power grids, threatens World Cup matches, and plays havoc with celebrations for America’s 250th independence anniversary.