If staff visit rooms immediately after the rooms have been vacated, they can switch off unnecessary lights and equipment. Many people believe that it is more energy efficient to leave fluorescent lights on when they are not needed. This is not the case. While switching fluorescent lights on and off more frequently reduces their life slightly, it is cheaper and environmentally preferable to switch fluorescent lights off when they are not required. Using key tags for appliances such as air conditioners, as well as lighting, improves potential benefits.
Good design is essential.
Reflective glazing will only reduce this to 200 watts per square metre, which is 20 times the heat that would enter through the same area of an insulated ceiling. Small areas of roof glazing can provide a lot of light. For example, one square metre of clear roof glazing in direct sun provides light equivalent to that supplied by about 30 fluorescent tubes. Roof glazing is not an effective way of collecting solar energy during winter, as the sun is low in the sky. North facing windows work much better in winter and are easily shaded in summer.