Method: Existing connected lighting load is: Existing Load = Number of Fixtures × Existing Fixture Wattage New connected load is: New Load = Number of Fixtures × New Fixture Wattage Demand reduction is: Demand Reduction = Existing Load − New Load Annual energy savings are: Energy Savings = Demand Reduction × Operating Hours Annual cost savings are: Cost Savings = Energy Savings × Electricity Tariff Fixture wattage should represent actual electrical input power, including ballast or driver losses where relevant. The calculator assumes the same number of fixtures and operating hours before and after the retrofit. Actual lighting retrofit design should also verify required illuminance, lumen output, light distribution, color quality, controls, fixture lifetime and applicable lighting standards. Additional savings from occupancy sensors, daylight controls or reduced cooling load are not included automatically.