1.   Hospitals, airports, sewage plants and urban areas would be exempted from these planned blackouts.

2.   On Thursday, the Independent System Operator had warned that planned blackouts might be required in late afternoon.

3.   The order has not stopped the state from suffering critical shortages in power, which caused the planned rotating blackouts in central and northern California on Wednesday and Thursday.

4.   These officials said they were forced to order the planned blackouts to avoid uncontrolled shutdowns that could have moved unpredictably through the system.

5.   Critics of the planned blackouts said power producers simply could sell their unused electricity to other states, or trim back production to keep supplies short.