Energy-saving guide for Northern Australia
Hot arid living
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 a range of things you can do for free that will reduce your 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. It has high summer temperatures and winter temperatures that vary greatly between day and night.
You may need to change some of your current household behaviours. If you’re already taking many of these actions, consider revisiting them, especially if you’ve changed living arrangements or are new to the region.
Simple things you can do now in hot arid climates
Capture cooler air or breezes
Opening windows and vents on opposite sides of the room provides cross-ventilation and helps to manage extremely hot summer temperatures by drawing cooler air through the building.
Cool breezes work best in narrow or open plan layouts
Breezes tend to occur in the late afternoon or early evening so it’s a good idea to open the house up when you come home. You could 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 hose. The design of your windows can help catch and deflect breezes from different angles and casement windows are particularly effective for this.
In summer, flush hot air out of rooms at night by opening windows and vents to draw in the cooler night air to help cool the thermal mass and keep temperatures comfortable. A house with high ceilings and vents will create convective air movement by giving hot air a place to go during the day and helping draw in cooler air at night.
Convection causes warm air to rise, drawing in cool air.
Night purging cools the thermal mass of a building and works well in hot arid climates where homes are usually designed with areas of exposed internal brick, tile or concrete and temperature changes between day and night are significant. Typically it's 6 to 8°C cooler at night.
Fans are very efficient and are cheap to buy and run (about 2 cents an hour). They can improve comfort levels so that you feel about 3°C cooler.
Fans cool by moving air across the skin so need to be close to you. Place 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 the two simultaneously allows you to operate the air conditioner more efficiently by running it 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 create wind barriers to block unwanted hot and dry winds. Deep, covered verandahs and balconies provide shade, cool incoming air and offer outside living areas to escape to.
Create your own evaporative cooling by planting vegetation in the path of hot dry 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.
If you have an existing wind break or water feature take advantage of the increased opportunities to cool down by opening up and capturing air movement or breezes.
Courtyard pools cool your home through evaporation
Shading and window coverings
Unprotected windows can be the biggest source of heat entering your home, up to 90%, so keeping the sun out will greatly reduce your need for mechanical cooling. Make use of existing adjustable shading such as awnings and blinds.
Blinds and curtains can be an effective solution, and are a good way to deal with problems with existing windows. Heavier fabrics and multiple layers of fabric give the best thermal protection.
When installing blinds, look for an insulating fabric and ensure they're well-fitted to restrict air movement around the window to prevent unwanted heat loss or gain. For an energy-efficient option, 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 is flexible and can be low cost
Pergolas covered with shade cloth or deciduous vines are a cost-effective way of providing seasonal shading and preventing 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.
In winter, adjust shading and open up shutters to allow the sun to heat your home. The Your Home website has more detailed shading information.
In areas that get cool at night during winter, allow the sun to warm your home during the day by opening up curtains and adjustable shading, blinds and awnings. Adjustable shading on the northern side allows in the lower-angle winter sun that can be blocked out in summer when cooling is required.
You can also dress for the occasion by rugging up with additional layers of clothing and using a light wrap or blanket while sitting for long periods in the evenings.
If you require additional heating, choose the most effective heater for your situation. Reverse cycle air conditioners can provide heating and cooling and have an energy rating label to help you choose the most efficient model. Gas heating has an industry-led rating system. Estimate running costs of your appliances by following our handy formula.
Open fireplaces can provide a cosy ambience on occasional winter nights. However, these 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. Remember to use sustainably sourced timber where possible.
The most effective forms of wood heating are properly installed slow combustion inserts and stoves. Follow our tips for running this type of heater effectively.
Quick, cost-effective changes for hot arid climates
Mind the gaps
One of the easiest and cheapest ways of increasing the effectiveness of cooling and heating systems is by draught-proofing your home. You can save up to 25% on your energy bill by reducing the amount of cooled (or heated) 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. These are available at most hardware stores.
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.
Paint your roof white
Lighter colours reflect heat and darker colours absorb it. Adding two coats of white exterior acrylic paint to roof areas 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 up to 20%. White roofs have an impact on energy consumption in winter due to making houses cooler.
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 clean your roof regularly. If the roof needs replacing consider using steel roofing solutions with reflective paint.
Monitor the weather
To help read your local weather more accurately, invest 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; for example, 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 80% less energy than a halogen light and lasts 5 to 10 times longer. They will also reduce the amount of heat in your home, particularly if you’re replacing halogen downlights which run hotter than other lighting technologies. 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 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.
Plant shade trees
While they can take a number of years to mature, trees are a great low-cost, low-energy solution. Planting the correct mix of trees and shrubs can provide shade, saving you money on your cooling costs, while also improving air quality and biodiversity.
Tree shade on the eastern and western sides of an older style single-storey, 3 star energy-rated home have 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 winter 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 for hot arid climates
Evaporative coolers (sometimes known as a ‘swampy’) are a highly effective alternative in hot, dry climates with low humidity such as Alice Springs. They add moisture to the air, are energy efficient and cheaper to run than an air conditioner of similar size, using around half the energy. Central systems are more effective than portable styles. Evaporative coolers use between 4 and 25l of water (or more) an hour on hot, dry days. They may not be suitable in areas with water restrictions. Look for a system that monitors water hardness and salinity and eliminates water selectively rather than continuously. Check the settings with your provider when your system is installed.
Evaporative coolers work best in climates with low humidity
Evaporative coolers don’t provide a heating function as a standard feature which reverse cycle air conditioners do. They can have gas heaters added to them to allow them to heat as well. Your household circumstances will determine if this is a worthwhile option. For example, whether you have gas connected.
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 inverter-driven fan. The option to run some units off a solar PV panel makes them an attractive energy-saving option.
During operation, some windows and doors must be open to allow hot air to escape from the house. To get the best out of your evaporative cooling system, carry out regular maintenance to keep the filter clean. Cover the roof unit and close off ducts in winter to reduce heat losses. 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.
The first line of defence in cooling your home is to stop it absorbing and storing the sun’s heat. Light-coloured roofs can reflect up to 70% of summer heat gain, helping to reduce the internal temperature and improve comfort levels.
The easiest time to install light-coloured roofing is when you’re building. However, if you need to replace your roof, steel roofing solutions with new reflective paint technology are a highly effective. Research to find an option that suits your budget.
Insulate your ceiling and roof
Insulation helps to keep the sun’s heat out of your home during extreme temperatures and traps warm air inside your home during cold days. This can save you up to 40% on your energy use.
Insulation can be sensibly and safely added to many existing homes. To take advantage of the improved comfort levels and energy savings that result from its installation, research the correct type and level of insulation for your building type and climate or talk to a knowledgeable building professional.
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, use of bulk and/or reflective insulation is recommended.
Under a sheet metal roof or a 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 should be insulated with reflective-foil insulation to reduce radiant heat gain, as this impacts on your indoor temperature as well as making outdoor seating areas uncomfortable. Consider installing energy-efficient ceiling fans.
Condensation needs to be considered in all roof and wall systems. Seek expert advice when designing and installing your reflective insulation system.
Insulating elevated floors with polystyrene foil-faced rigid board insulation, or similar, resists upward heat flow and condensation in summer and colder air flow on winter nights.
Go solar PV
With new developments in home battery storage, solar energy is becoming even more attractive to Australian households. Our guide to installing solar power 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. Approach an accredited installer to ask about the right size system.
You may be eligible for financial assistance to help with the cost of installing a solar PV system under the Australian Government’s Small-scale Renewable Energy Scheme (SRES). See the Energy.gov.au rebate pages for any assistance available and contact energy retailers to find out about feed-in tariffs.
Switch to an energy-efficient hot water system
Hot water can use 25% of your energy. If replacing your hot water system, take time to 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. See our detailed information on hot water.
For hot arid climates, heat pump and solar hot water are recommended technologies and you may be eligible for financial assistance to help with the cost of installing a system under the Australian Government’s Small-scale Renewable Energy Scheme (SRES). See the Energy.gov.au rebate pages for available assistance .
Ensure your installer recommends the most appropriate system for your climate, for example, a solar hot water system that is able to withstand occasional sub-zero temperatures. Periods of low temperature (under 5°C) can effect heat pump performance but this is unlikely to be a significant issue in hot arid conditions.
Evacuated tubes (left) and flat plate (right) solar hot water systems
Ensure you understand the information on safety and maintenance for your new system. This is particularly important for a storage hot water system that you’re switching back on after a period of non-use. The water needs to be heated to above 60°C for at least 35 minutes before use, killing any bacteria that may have grown. It could take several hours for the water to heat above 60°C.