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Hot arid living

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Staying comfortable in your home while reducing energy use doesn’t have to involve spending a lot of money. Whether you’re in Tennant Creek, Carnarvon or Longreach, there are things you can do for free that will reduce your energy bill while still keeping you and your home cool in summer and warm on winter nights.

Our tips focus on taking advantage of the climate-friendly features already in your home before resorting to the air conditioner. The actions you need to take in the hot arid zone change with the seasons.

Capture breezes

Opening windows and vents on opposite sides of the room provides cross-ventilation and helps manage hot summer temperatures by drawing cooler air through the building.

Floor plan of a home indicating air flow

Cool breezes work best in narrow or open plan layouts

Breezes tend to occur late afternoon or early evening so it’s a good idea to open the house at these times. Spend some time in shaded garden areas as the house cools.

Close everything up again in the morning before the outside temperature rises. Close doors and windows to exclude warmer winds from entering your home when these occur.

Cleaning your fly screens will help to promote the passage of cool air. This can be done with a brush or rhose. The design of your windows may help catch and deflect breezes from different angles. Casement windows are particularly effective.

Night purging

In summer, expel hot air from rooms at night by opening windows and vents to draw in the night air to help cool the thermal mass.

A house with high ceilings and vents will create convective air movement by giving hot air a place to go during the day and draw in cooler air at night.

Diagram showing night purging air flow

Convection causes warm air to rise, drawing in cool air

Night purging cools the thermal mass of a building and works well in arid climates where there are significant temperature changes between day and night. Homes are usually designed with areas of exposed internal brick, tile or concrete making them more conducive to night purging.

For more information on thermal mass see the Your Home website.

Fans

Fans are efficient and are cheap to run (about 2 cents per hour). They can improve comfort levels so that you feel about 3°C cooler.

Fans cool by moving air across the skin so they need to be close to you. Arrange furniture to take advantage of their effect and set up pedestal fans where ceiling fans don’t reach.

If you have high ceilings, consider lowering fans on droppers to avoid pushing any warm air near the ceiling down into the room. You can also use fans to increase the effectiveness of your air conditioner. Running both together allows you to operate the air conditioner more efficiently at a higher temperature setting for a shorter time.

Shop around for the most effective and energy-efficient fans. Noise levels and performance vary.

Wind breaks and water features

Take advantage of walls, temporary screens and landscaping that creates barriers against hot and dry winds.

Create your own evaporative cooling by planting vegetation in the path of summer winds. Trees used in combination with water features such as ponds or pools can help cool and humidify the air before it enters your home.

Deep, covered verandahs and balconies provide shade, cool incoming air and provide comfortable outside living areas.

Diagram of a house with a pool, demonstrating how a courtyard pool can cool the home through evaporation

Courtyard pools cool your home through evaporation

Shading and window coverings

Unprotected windows can be the biggest source of heat entering your home at up to 90%. Keeping the sun out will greatly reduce your need for mechanical cooling.

Make use of adjustable shading such as awnings and blinds. When installing blinds, look for an insulating fabric and ensure they’re well-fitted to restrict air movement around the window to prevent heat loss or gain. Honeycomb or cellular blinds are an excellent choice as they trap air within cells and act like a double-glazed window.

You’ll achieve even better results by blocking heat from passing through the glass. It’s recommended to shade all external doors and windows if your home doesn't require winter heating. In regions where heating is needed, use passive solar shading to the north to allow winter sun in.

shade cloth on a side of a house

Pergolas covered with shade cloth or deciduous vines are a cost-effective way to provide seasonal shading and prevent heat gain in summer. They can be used in combination with plantings of deciduous trees.

Growing vines or plants up walls on any side of your house will also provide an insulation effect in summer. If you don’t want to block winter sun, avoid using evergreen vines except on the western side of your house where heat gain is significant.

For more information on shading see the Your Home website.

Winter warmth

In areas that get cool at night, let the sun warm your home during the day by opening up curtains and adjustable shading, blinds and awnings. Adjustable shading on the northern side lets in the lower-angle winter sun that can be blocked out in summer.

If you need additional heating, choose the most effective heater for your situation. Reverse-cycle air conditioners provide heating and cooling and have a government-administered energy rating label to help you choose the most efficient model.

Wood fires

Open fireplaces can provide a cosy ambience, however they only provide radiant heat and are an inefficient way to keep warm. Up to 90% of the heat goes up the chimney, drawing in cold air to replace it.

The most effective forms of wood heating are properly installed slow combustion inserts and stoves.

Mind the gaps

One of the easiest and cheapest ways of increasing the effectiveness of cooling and heating systems is draught-proofing your home.

You can save up to 25% on your energy bill by reducing the amount of air leaking from cracks and gaps around windows and doors.

Gap filler is a simple, cheap way to fill gaps along skirting boards, while draught-stoppers are useful for gaps under doors. You can also buy covers for exhaust fans and evaporative cooling ducts to use during winter. 

A simple way to identify air leaks is to close up your house and hold a lit incense stick around the edges of windows and doors. If the smoke is drawn inwards this indicates an air leak.

For more information see the Heating and cooling page.

Paint your roof white

Lighter colours reflect heat and darker colours absorb it. Adding 2 coats of white exterior acrylic paint to roofing will reduce heat gain into your home.

This simple action improves internal comfort by around 3°C and reduces the need for air conditioning by as much as 20%.

Man compression painting a roof white

Paint your roof white to reflect the heat [Alice Springs solar city]

If your home is not currently insulated, it’s a good idea to install insulation before painting. Choose a paint product that will help repel dust from accumulating, and ensure you clean your roof regularly. If your roof needs replacing you may wish to consider steel roofing solutions with reflective paint technology.

Monitor the weather

To help read your local weather more accurately, consider investing in a home weather station with an indoor display or alert system.

These range from inexpensive temperature gauges to digital technology that can measure solar radiation, expected rainfall, wind speed and direction, humidity and more.

By providing you with a convenient read-out from inside the home, they can help you to respond to outside conditions and manage your home more efficiently. An example is by allowing you to operate blinds and awnings effectively and capture passing breezes as they occur.

Switch to energy-efficient lighting

While they might cost more upfront to buy, LED lighting is much more efficient than other forms of lighting and will save you money over the long term.

A good quality LED bulb consumes 75% less energy than a halogen light and lasts up to 25 times as long. They will also reduce the amount of heat in your home, particularly if you’re replacing halogen downlights.

It takes up to 6 downlights to light the same area as one pendant light, so switching to LED bulbs and pendant lighting can have a real impact.

As downlights require a minimum clearance around ceiling insulation they can reduce the effectiveness of insulation. This is another reason why pendant, ceiling-mounted or track lighting is a better option. Ask a lighting specialist to provide approved covers with your LED downlights to reduce the impact on the insulation. Sealed downlights are another option.

For more information see the Lighting page.

Plant shade trees

Planting the correct mix of trees and shrubs provides shade, saving you money on your cooling costs, while also improving air quality. Consider purchasing saplings to provide immediate shade.

Tree shade on the eastern and western sides of an older style single-storey, 3 star energy-rated home has been shown to provide energy savings of up to 50%.

Shade is particularly important if your home is made of heavier construction that takes longer to cool down. Trees with high branches are useful for shading roofs, while shrubs can help shade windows.

Deciduous plants allow sun to enter your home in winter, blocking it during the hot summer months.

Trees can also be used to filter hot summer winds, cooling them before they hit your home. This is especially effective in combination with water features.

Talk to your local nursery about what species do best in your area and where to plant them as part of your garden research.

Longer term investments

Evaporative cooling

Evaporative coolers are a highly effective alternative in hot, dry climates with low humidity such as Alice Springs. They add moisture to the air and are cheaper to run, using around half the energy of a similarly-sized air conditioner.

Central systems are more effective than portable units, and the ability to run some units off a solar PV panel makes them an attractive energy-saving option.

Evaporative coolers use between 4L and 25L of water (or more) per hour on hot, dry days. They are therefore not ideal in areas with water restrictions. Look for a system that monitors water hardness and salinity. Check the settings with your provider when your system is installed.

Diagram showing how evaporative cooling works

Evaporative coolers work best in climates with low humidity

Evaporative coolers don’t provide a heating function as a standard feature, unlike reverse-cycle air conditioners. They can have gas heaters added to them.

Research to see if an evaporative cooler will provide the right level of comfort for your circumstances. Choose a model with a thermostat, a timer and an inverter-driven fan.

During operation, some windows and doors must be open to allow hot air to escape from the house. Cover the roof unit and close off ducts in winter to reduce heat losses.

To get the best out of your evaporative cooling system, carry out regular maintenance to keep the filter clean. Consider getting a professional in every few years to de-scale the pads, check the fan pump, tighten fan belts and adjust the bleed rate.

Insulate your ceiling and roof

Insulation can be sensibly and safely added to many existing homes. To take advantage of the improved comfort levels and energy savings, research the correct type and level of insulation for your building and climate.

The use of bulk and reflective insulation in the ceiling and roof is recommended. In the ceiling select R3.5 or higher bulk insulation. For walls, bulk and/or reflective insulation is recommended.

Consider installing energy-efficient ceiling fans. Condensation needs to be addressed in all roof and wall systems. Seek expert advice when designing and installing your reflective insulation system.

For more information on insulation see the Your Home website.

Sheet metal or tiled roofs

Under a sheet metal or tiled roof, a reflective insulation system should be used.

A tiled roof should have sarking—a double-sided reflective-foil product under the tiles—as well as ceiling insulation.

Including a foil-blanket system under sheet metal roofing can provide an additional benefit of dampening the sound of heavy rain.

Verandah roofs

Verandah roofs should be fitted with reflective-foil insulation to reduce radiant heat gain, which impacts on your indoor temperature as well as making outdoor seating areas uncomfortable.

Floors

Insulating elevated floors with polystyrene foil-faced rigid board insulation or similar, resists upward heat flow and condensation in summer and colder airflow on winter nights.

Go solar PV

With new developments in home battery storage, solar energy is becoming even more attractive for households. Our Solar PV and battery page has more information.

To assess the benefits, get an estimate of how much electricity you use each year and the power you can generate in your particular location. Ask an accredited installer about the right size system.

You may be eligible for financial assistance towards the cost of installing a solar PV system under the Australian Government’s Small-scale Renewable Energy Scheme (SRES). See our rebates page and contact energy retailers to find out about feed-in tariffs.

For more information on solar PV see the Your Home website.

Switch to an energy-efficient hot water system

Hot water can account for around 25% of your energy use. If replacing your hot water system, research the right type and size of product for your needs. Choose the most suitable and energy-efficient model you can afford to save on energy bills, and avoid paying for capacity you don’t need.

For arid climates, heat pump and solar hot water are recommended technologies. You may be eligible for financial assistance to help with the cost of installing a system under the Small-scale Renewable Energy Scheme (SRES).

Your installer should recommend the most appropriate system for your climate. For example, a solar hot water system that is able to withstand occasional low or sub-zero temperatures where appropriate.​