A yearlong experiment with America's electric grid could negatively impact home systems and appliances that have a clock that does not work off a computer or the Internet.

Since 1930, electric clocks have kept time based on the rate of the electrical current that powers them. If the current slips off its usual rate, clocks run a little fast or slow. Power companies now take steps to correct it and keep the frequency of the current, and the time, as precise as possible. The group that oversees the U.S. power grid is proposing an experiment that would allow more frequency variation than it does now without corrections, according to a company presentation obtained by The Associated Press.

Tweaking the power grid's frequency is expensive and takes a lot of effort, said Joe McClelland, head of electric reliability for the Federal Energy Regulatory Commission. “Is anyone using the grid to keep track of time?” McClelland was quoted as saying. “Let's see if anyone complains if we eliminate it.”

No one is quite sure what will be affected.