Many people look at their energy bills with disdain due to the rising cost of power. The main areas of power use in the home typically include central air conditioners and heating/cooking.

Is there scope for bill-reduction? Certainly! If we just examine the central air conditioning system for example, it may well be possible to significantly reduce the power usage, and hence the bill, by adhering to some simple rules.

Surely raising the thermostat temperature is the only way?

Not true! Extractor fans fitted to most bathrooms and kitchen hoods have surprisingly high air flow rates. A whole room of air can be emptied by an extractor fan according to the following approximated table;

single Kitchen  10-15 times per hour
Bathroom   6-8 times per hour
Bathroom with shower 15-20 times per hour
WC   6-10 times per hour

These flow rates are not particularly surprising. But, when applied to the total volume of air in a home, indicate that leaving just one extractor fan running e.g. in a WC or bathroom, is going to empty the equivalent (assuming a bathroom is only 1/3 the size of a regular room) of an 8 room house in just a few hours. So leaving the house with just one extractor running in a bathroom, (as kids are prone to do), can result in the central air conditioner working flat out to keep up and a bill to match!

So what can be done to reduce this huge waste of your hard-earned money?

There are some very simple solutions - other than remembering to turn off extractors when not needed:

1) Ensure that the bathroom extractors are linked to the light switch, people are much more likely to remember to switch off the light! OR:

2) Fit timers to extraction fans to limit their on-time. These cost little and will pay for themselves really quickly in energy cost savings.

3) Ensure that the extractors in your house are correctly rated for the room size and application.

So pay attention to not just the air you lose incidentally from your house, but the air you discard – it all costs money to cool!