The patterns of electricity consumption were studied for 27 representative dwellings in Northern Ireland. The type of dwelling, its location, ownership and size, household appliances, attributes of the occupants including number of occupants, income, age and occupancy patterns have differing but significant impacts on electricity consumption. A clear correlation was found between average annual electricity consumption and floor area. The monthly consumption of detached houses is between 3.57 and 5.17 kWh m(-2); semi-detached between 3.44 and 4.59 kWh m(-2) and terraced houses between 2.5 and 3.9 kWh m(-2). The average winter consumption exceeded the average summer consumption by 1.59 kWh m(-2) for detached, by 1.16 kWh m(-2) for semi-detached and by 1.78 kWh m(-2) for terraced houses. The difference in the annual demand on the grid between detached and terraced houses is between 24 and 30%. The electricity consumption per person decreases as the number of occupants increases. This is particularly significant in large dwellings but smaller numbers of occupants. (C) 2007 Elsevier B.V. All rights reserved.