22   Efficient electricity use

Can we cut electricity use? Yes, switching off gadgets when they’re not in
use is an easy way to make a difference. Energy-efficient light bulbs will
save you electricity too.

We already examined gadgets in Chapter 11. Some gadgets are unim-
portant, but some are astonishing guzzlers. The laser-printer in my office,
sitting there doing nothing, is slurping 17 W – nearly 0.5 kWh per day! A
friend bought a lamp from IKEA. Its awful adaptor (figure 22.1) guzzles
10 W (0.25 kWh per day) whether or not the lamp is on. If you add up a
few stereos, DVD players, cable modems, and wireless devices, you may
even find that half of your home electricity consumption can be saved.

According to the International Energy Agency, standby power con-
sumption accounts for roughly 8% of residential electricity demand. In
the UK and France, the average standby power is about 0.75 kWh/d per
household. The problem isn’t standby itself – it’s the shoddy way in which
standby is implemented. It’s perfectly possible to make standby systems
that draw less than 0.01 W; but manufacturers, saving themselves a penny
in the manufacturing costs, are saddling the consumer with an annual cost
of pounds.

A vampire-killing experiment

Figure 22.2 shows an experiment I did at home. First, for two days, I mea-
sured the power consumption when I was out or asleep. Then, switching

Figure 22.1. An awful AC lamp-adaptor from IKEA – the adaptor uses nearly 10 W even when the lamp is switched off!
Figure 22.2. Efficiency in the offing. I measured the electricity savings from switching off vampires during a week when I was away at work most of each day, so both days and nights were almost devoid of useful activity, except for the fridge. The brief little blips of consumption are caused by the microwave, toaster, washing machine, or vacuum cleaner. On the Tuesday I switched off most of my vampires: two stereos, a DVD player, a cable modem, a wireless router, and an answering machine. The red line shows the trend of “nobody-at-home” consumption before, and the green line shows the “nobody-at-home” consumption after this change. Consumption fell by 45 W, or 1.1 kWh per day.