4 Saving electricity
Cutting electrical demand in buildings requires tackling a whole range of uses including the lifestyle changes that increased electricity use has brought to our society.
Mains electricity started as a lighting technology, but then rapidly diversified into motive power and then a host of electrical appliances. Many ‘labour-saving’ devices like vacuum cleaners and washing machines were introduced in the 1920s and 1930s to cope with a ‘servant shortage’ after World War I. Refrigerators and freezers have allowed shopping to be done once a week rather than daily and allowed the storage of pre-packaged convenience foods.
In parallel there has been a growth of ‘electronic entertainment’, for example radio, television, hi-fi, and the computers and internet for fun rather than work (see Energy Saving Trust, 2006,).
It raises questions of what exactly is the modern ‘good life’? Is it just one of owning lots of appliances to make our life easier so that we can slump in a chair and be entertained by the latest electronic gadgets (Figure 38)?
Figure 39 shows the growth in UK ownership of some of these appliances since 1970. Given that the number of UK households grew from 19 million in 1970 to nearly 27 million in 2010, the average 2010 household would appear to own 1 home computer and 2.2 televisions.
Looking to the future, the UK population is likely to increase from 62 million in 2010 to around 67 million by 2050. The average household size is also falling. In 2010 it was about 2.3 persons per household, but this is likely to fall to 2.1 persons by 2050. The total number of households could thus rise to nearly 32 million by 2050 (Boardman et al., 2005). Into every new household goes another set of appliances.
In 2010 electricity use for cooking, domestic appliances and lighting amounted to about a quarter of national electricity demand. Figure 40 shows the trends in consumption since 1970 for different categories. Although programmes of promoting energy efficient lighting and fridges appear to have had an effect since 2000 (and dramatically so since 2007), the gains have been counterbalanced by the growth in consumption by a host of other electronic devices: TVs, mobile phones, home computers, etc.