By Tim McLaughlin BOSTON, Jan 24 (Reuters) - U.S. electric grid operators on Saturday stepped up precautions to avoid rotating blackouts as frigid weather hitting half of the country's population stressed their operations.

Midcontinent Independent System Operator asked residents Saturday to conserve electricity amid Winter Storm Fern to help maintain grid reliability.

Chances are increasing that a winter storm will bring snow, ice, and plunging temperatures to millions across Texas this week.

They typically just make sure they get the kids safely to and from school. But Shawnee public schools is also using their electric vehicles for a shocking surpr