Gulf Power and Florida Power and Light are planning to ask state regulators for a new four-year rate plan that will bring the two companies under the same rate structure. Gulf Power said the plan will result in lower bills for its Northwest Florida customers at the end of the four-year plan while other Florida customers will see an increase. The company said the typical Gulf Power customer pays $140 a month for electricity while the typical Florida Power & Light customer pays $99 a month. Florida Power & Light customers will see about a 3.5% increase in rates over four years while Gulf Power customers’ bills would be lower than they are today.