DETROIT (WWJ) - This weekend we’ll begin the switch to a more efficient light bulb in the U.S.

WWJ’s Sandra McNeill reports that on Sunday, the US will begin phasing in new rules for light bulbs that were passed by Congress in 2007.

Under the new rules, all bulbs are required to have labels that tell consumers how bright they are, how long they last and how much they cost to operate. The rules will also require 100-watt bulbs to be 25-percent more energy-efficient. Lower wattages will be phased in through 2014. The more energy-efficient bulbs will cost more to buy, but will be cheaper to operate over a year.

But, there’s a catch: Under a measure introduced with a spending bill by Republicans last month, the government can’t do anything about manufacturers who don’t follow the new rules until September.

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