Domestic lighting: a high-resolution energy demand model

The use of electric lighting in the domestic sector depends mainly on the level of natural light coming in from outdoors, coupled with the activity of the household residents. This paper presents a detailed model of domestic lighting use that takes these two factors as its basic inputs. The operation of individual bulbs is represented within the model and is used to construct high-resolution lighting electricity demand profiles for individual dwellings. The model is computationally efficient and can easily provide data at one-minute resolution for large numbers of dwellings. As a primary input, the model uses a time-series representing the number of active occupants within a dwelling (people who are at home and awake). This allows it to represent the sharing of lighting between the occupants of a given dwelling and facilitates correlated linking to models of other energy use within the dwelling. Appropriate correlation between dwellings is achieved through the use of appropriate active occupancy data and outdoor ambient light data. An example implementation of the model in Microsoft Excel is available for free download.