Home air conditioning in Europe – how much energy would we use if we became more like American households?

Panel: Panel 2. Making buildings more energy efficient

Author:
George Henderson, Independent consultant

Abstract

Relatively few homes in Europe currently have air conditioning, which accounts for a small proportion of household electricity use by European households. In the United States of America, however, the 2001 Residential Energy Consumption (RECS) survey showed that three-quarters of all American households use electric air-conditioning and that it accounted for 16% of all household electricity use in the survey year. Much of the difference between Europe and North America may be attributed to climate but it is clear that other factors, including expectations of thermal comfort, also play a large part.

The information gathered by RECS includes the number of households with central and room air conditioning, conditioned floor area, average energy consumption per household and cooling degree days. Results are given separately for each of the 9 Census Divisions of the USA and the four most populated states: California, Florida, New York and Texas. This enables the use of air conditioning to be related to cooling degree days (CDD) and floor area. Despite relating to large areas that individually encompass substantial climatic diversity, the data show a strong correlation between energy use and degree-days. Other research used data from 39 American cities to establish the relationship between degree days and uptake of home air-conditioning systems.

This paper uses the relationships derived from American household data to estimate how much energy might be used at various locations in Europe if American uptake and usage patterns were to be followed. The results are compared with the projections made as part of the SAVE project on the Energy Efficiency of Room Air Conditioners (EERAC).