This paper presents a new model of domestic lighting demand. The model is based on half-hourly data measured for a sample of 100 UK homes. It represents one sub-model in an end-user based distributed load model that is being developed to support investigations into the effects on low voltage urban electricity networks of future wide-scale uptake of solar technologies. To capture these effects and to serve applications involving renewable energy technologies (RETs) generally, the model is capable of representing load variations on very fine time-scales, down to 1 min intervals. Additionally, scaling factors are provided to enable prediction of long-term trends and to model some of the most important elements of diversity between connection points that are likely to impact on network performance and design below the 11 kV substation level. (C) 2003 Elsevier B.V. All rights reserved.