Electrical demand is driven by economic and human activity, which has obvious daily, weekly and yearly cycles as well as a long-term trend and special periods such as bank holidays, Christmas etc., all of which are reflected in load data. These characteristics of electrical demand must inevitably be incorporated into any demand-forecasting model. However, with the exception of a few papers, the vast bulk of the literature on electrical demand forecasting is concerned with forecasting techniques. This paper proposes several methods with which to quantify the characteristics of Irish electrical load data prior to modelling