CB 121231: An ordinance relating to the City Light Department; establishing new retail rate schedules; establishing a new customer class and conditions of service for data centers whose electricity demand constitutes a new large load; modifying customer charges for service connections; modifying customer eligibility for residential rate assistance; augmenting the rate stabilization account mechanism; amending Sections 21.49.020, 21.49.030, 21.49.040, 21.49.052, 21.49.055, 21.49.057, 21.49.058, 21.49.060, 21.49.065, 21.49.083, 21.49.086, 21.49.110, and 21.49.130 of the Seattle Municipal Code; adding a new Section 21.49.059 to the Seattle Municipal Code; and repealing Section 21.49.081 of the Seattle Municipal Code.