Lighting Loads

Converting a building to more efficient lighting sources reduces energy consumption and peak electric demands. You can estimate energy consumption using the following guidelines:

1. General fluorescent lighting systems, such as in an office building, have lighting loads of 1.5 to 2.5 watts per square foot,

2. A fluorescent lighting system with both task and ambient lighting has a lighting load of 1.2 to 4.0 watts per square foot,

3. An HID (High Intensity Discharge) lighting system has a load of 1.0 to 2.0 watts per square foot, and

4. Every 2.0 - 3.0 kW of lighting load requires an additional kW of cooling. Theoretically therefore, every 1 kW reduction in lighting often results in a 1.3 -1.5 kW drop in total energy.