off all the gadgets that I normally left on, I measured again for three more
days. I found that the power saved was 45 W – which is worth £45 per year
if electricity costs 11p per unit.

Since I started paying attention to my meter readings, my total electric-
ity consumption has halved (figure 22.3). I’ve cemented this saving in place
by making a habit of reading my meters every week, so as to check that the
electricity-sucking vampires have been banished. If this magic trick could
be repeated in all homes and all workplaces, we could obviously make
substantial savings. So a bunch of us in Cambridge are putting together
a website devoted to making regular meter-reading fun and informative.
The website,, aims to help people carry out similar ex-
periments to mine, make sense of the resulting numbers, and get a warm
fuzzy feeling from using less.

I do hope that this sort of smart-metering activity will make a difference.
In the future cartoon-Britain of 2050, however, I’ve assumed that
all such electricity savings are cancelled out by the miracle of growth.
Growth is one of the tenets of our society: people are going to be wealthier,
and thus able to play with more gadgets. The demand for ever-more-super-
lative computer games forces computers’ power consumption to increase.
Last decade’s computers used to be thought pretty neat, but now
they are found useless, and must be replaced by faster, hotter machines.

Notes and further reading

page no.

155Standby power consumption accounts for roughly 8% of residential electricity.
Source: International Energy Agency (2001).
For further reading on standby-power policies, see:

Figure 22.3. My cumulative domestic electricity consumption, in kWh, each year from 1993 to 2008. The grey lines show years from 1993 to 2003. (I haven’t labelled these with their years, to avoid clutter.) The coloured lines show the years 2004 onwards. The scale on the right shows the average rate of energy consumption, in kWh per day. The vampire experiment took place on 2nd October 2007. The combination of vampire-banishment with energy-saving-lightbulb installation reduced my electricity consumption from 4 kWh/d to 2 kWh/d.