Ceiling Fans and Air Conditioning: How to Stay Cool for Less This Summer

Above: a large ceiling fan installed by I.C.M.

Summer in South East Queensland means hot, sticky nights and an air conditioner working hard. A ceiling fan won't replace air conditioning on the worst days. Used well, though, it can keep you comfortable on far less electricity, and it can help your air conditioner work less when you do need it.

Here's how ceiling fans and split systems compare, roughly what each costs to run, and what an electrician checks before a fan goes up.

A ceiling fan cools you, not the room

A ceiling fan doesn't lower the air temperature. It moves air across your skin, which helps sweat evaporate and makes you feel cooler. That has two practical consequences:

• A fan only helps while someone is in its breeze, so turn it off when you leave the room.
• On humid nights, air movement is often what makes the difference, even when the thermometer barely changes.

A split-system air conditioner actually removes heat (and some moisture) from the room. That's why it wins on the hottest days, and why it uses far more power.

What they cost to run: a worked example

Running costs depend on the model, the setting, the weather and your electricity rate. Treat these figures as an illustration only. They are not a quote or a promised saving.

Assumptions

• Electricity rate: 35 cents per kWh. Your actual rate is on your bill and varies by retailer and tariff.
• Ceiling fan: 50 watts on a medium-to-high setting. Fans vary, and DC-motor fans generally use less. Check the rated power of the model you're considering.
• Split system: 0.8 kW of electricity while it's actively cooling. This is the electrical input, which is lower than the cooling capacity printed on the unit (for example, a "2.5 kW" unit). Actual draw rises and falls with the outdoor temperature, the thermostat setting and how well the room holds its cool.
• Run time: eight hours overnight.

Results

• Ceiling fan: 0.05 kW × 8 h = 0.4 kWh, or about 14 cents a night.
• Split system: 0.8 kW × 8 h = 6.4 kWh, or about $2.24 a night.

On these assumptions, the fan uses about one-sixteenth of the electricity. Your own figures will differ, but the gap is usually large. Australian Government energy advice also describes fans as much cheaper to run than air conditioners.

Using a fan and air conditioner together

You don't have to choose one or the other. With a fan running, most people feel comfortable at a higher air-conditioner setting.

• Set the air conditioner between 25 and 27 °C in summer, in line with Australian Government energy advice. Each degree warmer can cut cooling energy costs by roughly 5 to 10 per cent.
• Run the fan in its summer setting so it pushes air down onto you. The control differs between brands, so check the manual.
• Close blinds, curtains and internal doors during the hottest part of the day so you're only cooling the rooms you use.
• On milder nights, try the fan on its own first.

Choosing a ceiling fan

• Motor: DC-motor fans generally use less power than AC-motor fans and often have more speed settings.
• Speeds and reverse: look for at least three speeds and a reverse (summer/winter) function. Reverse helps in winter in heated rooms, especially those with high ceilings.
• Size and ceiling height: the fan should suit the room and leave safe clearance under the blades. Low or raked ceilings may need a particular fan or mounting kit.
• Light and controls: decide whether you want a light, a wall control, a remote, or a combination.
• Outdoor areas: a covered patio or alfresco needs a fan the manufacturer rates for that location and its exposure to weather. An indoor fan isn't suitable outside.

Installing a ceiling fan: what we check

In Queensland, installing a ceiling fan, including replacing a light fitting with a fan, is electrical work and must be done by a licensed electrician. The Electrical Safety Office warns that unlicensed electrical work is illegal and that an insurer may refuse a claim for a fire it causes.

Before we quote, we check:

• Fixing and support: the fan must be secured to the ceiling structure in line with the manufacturer's instructions, not just to the plasterboard.
• Blade clearance: the blades need enough height above the floor and clearance from walls, cupboards and other fittings.
• Wiring and switching: the condition of the existing circuit and light point, and what's needed for a wall control or a fan-and-light combination. Older homes sometimes need wiring work first.
• Location: the fan's rating suits where it's going, particularly outdoors.
• Access: ceiling height and access to the roof space.

If an existing fan wobbles badly, rattles, runs hot or smells of burning, switch it off and have it checked.

Get a written quote

Thinking about a new fan, or replacing a tired one? Send us:

1. Your suburb.
2. How many fans you're after, and which rooms or areas.
3. Whether you're replacing existing fans or adding new ones.
4. A photo of the ceiling or existing fan, taken from floor level.
5. The approximate ceiling height, if you know it.

We work across Ipswich, the Lockyer Valley and Somerset.

Request a written quote · Our residential services · Call 0407 705 917

Sources

• Australian Government, energy.gov.au: Summer energy savings
• Sustainability Victoria: Fans
• Electrical Safety Office Queensland: Don't do your own electrical work

Ian Christopher Matthews, trading as I.C.M. Electrical Contractor Licence No. 1507486.