Measuring Lighting Performance

You cannot manage lighting energy you have not measured, and a short survey with simple instruments turns vague impressions ("the lighting looks old") into hard numbers that justify projects and, afterwards, prove they worked. Lighting is unusually easy to measure: a lux meter and a power meter, plus a note of the operating hours, are enough to build a costed, ranked programme. This lesson covers measuring light levels, measuring power, calculating savings, and verifying that control savings are real.