Designing your home or business so that it complements the Territory’s hot climate through passive cooling is the first step to maximising your energy efficiency.

Passive cooling includes making the most of natural breezes, shading out the hot sun and using materials which reflect heat rather than absorbing it. It also includes planning residential and urban spaces to make the most of natural breezes, create green corridors and reduce the ‘heat island’ effect.

Check out Your Home a free online resource for plenty more reading on exactly how to design a home that incorporates passive cooling (and other passive design principles in the Top End!) 

Choosing appliances with a high Energy Star Rating will reduce your energy use over the long term.

The Energy Rating Label is a government initiative allows you to compare the energy efficiency and running costs of appliances before you buy – to reduce your electricity bill. Visit their website for more information on: 

• How to read an Energy Star Rating Label
• What does energy consumption mean?
• A product guide through all the different appliances (fridges, dishwashers etc)
• & so, so much more!! 

And another thing? Don’t buy any appliances which you don’t really need. Think if you can borrow a friend or neighbours before investing! 

You thought you could just install an air-conditioner and leave it to run? Is this humid climate? Wrong!

Regularly cleaning and servicing your air-conditioner, ceiling fans, screens as well as ensuring your fridge seals properly will significantly reduce your energy use.

With its mostly clear skies, the NT is a hotspot for solar energy. Rooftop solar using photovoltaic (PV) panels is a relatively cheap and easy way to reduce your energy bill and your climate impact.

It involves installing solar panels on your rooftop which turn the sun’s natural energy into electricity through an inverter.  When you’re not using the electricity, it feeds into the grid. Or if you connect the inverter to a battery the energy can be saved here until you need it. Check out COOLmob's Guide to Going Solar for more information. 

Installing a solar hot water system is also a cheap and easy way to make the most of the free solar energy we receive in the NT and reduce your energy bills.

For further information, see Environment Centre NT's Repower NT campaign. 

Depending on where you live in the NT, your electricity may come from the burning of natural gas, the burning of diesel or solar generation.

Solar electricity from solar panels on your rooftop generates zero climate pollution so is therefore the most sustainable energy source.

Darwin

Electricity is generated from natural gas at the Channel Island power station (310MW) and Weddell Power Station (129MW).

Alice Springs

Electricity is generated by the Uterne Solar Power Station (4.1MW), from natural gas at the Ron Goodwin Power Station (45MW) and from natural gas and diesel at the Owen Springs Power Station (36MW).

Tennant Creek

Electricity is generated from a mix of natural gas and diesel at the Tennant Creek Power Station (17MW).

Remote Communities

Electricity is generated by a mix of diesel and solar PV, depending where you live.

For more information, see Territory Generation

How you live in your home makes a huge difference to the power bill each quarter. Even if you had an amazingly sustainable design and only 5 Star Rated appliances, if you have ‘energy hungry behaviours’ your power bill won’t be as low as it could. 

Small and FREE wins can be made in any home by adjusting your behvaiour. These include:

• turning off the lights when you leave the room
• turning off electrical appliances at the wall
• using the cold water setting on your washing machine
• waiting for a full load before turning on the dishwasher
• using a fan before an air-conditioner
• setting your air-conditioner to 24 – 28 degrees
• making sure all doors and windows are closed when using air-conditioning
• setting your pool pump timer so it runs between 6pm and 6am 

Alternatives to air conditioners

Try cooling down by the following ideas to reduce the time you're running the air-conditioner:

• taking a cold shower before going to bed
• cool the room for 20 minutes before sleeping
• set the timer to switch off after you go to sleep or set to sleep mode
• use the fans instead
• only put the air conditioner on when necessary
• turn the air conditioner up a few degrees and take off the covers

Did you know that the cooler the temperature you set your air conditioner, the more it costs you to run? Every degree you lower the thermostat, you increase running costs by 10%! All air conditioners are designed to produce air at 17-18°C. They will pump out air at 17°C until the room reaches the temperature you set on your controller.

COOLmob have found that 30% of Darwin residents sleep without air conditioning in the wet season.

Tips on using your air conditioner so it uses less electricity

• If you run a fan when you have the air conditioner on you can turn the thermostat up a few degrees while still feeling comfortable. The air conditioner will reduce the humidity and the fan will cool you by increasing the air flow across your skin. Every degree warmer you set your air conditioner temperature control will save you money. Many people find 27-28°C (‘dry’ season temperatures) a comfortable setting for air conditioners when a room fan running.
• Check all windows and doors are properly closed and well sealed. Buy door strips/draught stoppers to prevent cool air escaping from your air conditioned rooms and have good insulation.
• Check the air conditioner is not in the sun. Have air conditioners fitted to a shaded wall area or try to create shade so the air entering the air conditioner is cool. That way the air conditioner does not have to work so hard to cool your air.

Did you know?!

A small air conditioner (<2kW) running for 10 hours a day every day of the year will cost between $292 – $584 per year while a large 3.5kW air conditioner run for the same time will cost between $510 – $1920 per year. Passively cooled houses have less need for air conditioners so save you lots of money.

An inverter air conditioner run for similar periods will cost approximately 30% less. New ‘solar’ air conditioners can save additional cost on power bills too.

It is a myth that fans reduce the temperature of rooms, so leaving them on while you are away will have no affect on the room’s temperature. 

Myth-busting fans facts

1. “Fans are cheap to run” - WRONG! A large ceiling fan uses 60-80 Watts. If never switched off this adds up to $136-181 a year for one ceiling fan. Six ceiling fans that are always left on will use between $816- $1086 a year! Fans are cheaper to run than air conditioners but make sure you turn them off when you leave the room. Smaller fans and lower speeds use less energy.
2. “Fans keep the house cool" - WRONG! Fans cool people as the moving air evaporates moisture off bare skin. Fans do not have a significant impact on inside temperatures.
3. “You have to leave the fans running to stop mould growth” - Mostly WRONG! Many people have told COOLmob that when they first moved to Darwin people told them to keep their fans running to reduce mould growth during the wet season. However many Darwinians keep their fans turned off unless they are using rooms. They find that, as long as they keep the windows open while they are out, and their house is dry and clean (mould needs dust or dirt to grow), they do not have problems with mould growth.

More information on environmentally-friendly ways of keeping mould at bay are in COOLmob’s Greenhouse-Friendly Habits for Top End Households booklet.

What is stand-by power?

Stand-by power is the power used by your appliances even when they have been switched off using a remote control, or are switched off at the appliance alone (and not at the wall). This means that you are still paying for things that should be turned OFF.

Measurements done by COOLmob on stand-by power used by individual appliances in the average household have shown that power is still consumed unless completely switched off. Possible savings of between $50 - $150 per year are possible from switching off appliances at the power point.

How do you know if you are using stand-by power?

You can calculate the amount of power you waste on stand-by power easily. 

1. Turn off everything else that uses power in your home (such as the lights, air conditioners, fans, fridges, hot water heaters, pool pumps etc);
2. Leave on items that have stand by mode (such as TVs, microwaves, stereos, chargers, entertainment systems etc);
3. Measure how much power is being used when these larger items are turned off. You can do this by counting the number of times that the wheel in the electricity metre takes to go around.

You can also hire a Power Mate Lite from any of the Darwin City Council libraries to measure how much stand by power is costing you each year.

What items are costing YOU money when left in stand-by?

You would be surprised to learn what products use stand-by power, and the only way to be sure that “OFF MEANS OFF” is to turn appliances off at:

1. The power point;
2. A switched power board or eco-switch (which you can purchase from COOLmob); or
3. The switchboard.

Consider that…

A little bit of stand-by power, multiplied by a lot of appliances in your home, multiplied by the number of times people are not using their appliances, multiplied by all of the households in the world leaving stand-by power on…results only in the a huge waste of money and the needless emissions of greenhouse gases!

The changing global climate and rising price of electricity means that our hard earned dollars are too precious to waste on equipment that we think we have switched off.

The two most common types of hot water systems for households are solar hot water systems and electric hot water systems. The main difference between these are that one uses electricity from renewable energy sources, and therefore heats your water for free using sunlight, and the other uses electricity from the grid.

Hot water heating from electric systems makes up a major portion of your electricity bill, so when choosing a hot water system for you home always consider the ongoing and ever-increasing costs of electricity consumption. 

COOLmob recommend you take a look at the Australian Energy Foundation Guides on different hot water systems, as they compare the most efficient systems and have recently published The Complete Guide To Choosing Your Perfect Heat Pump Hot Water System. 

Solar Hot Water Systems

Using the sun to heat your hot water is free. In order to heat water using solar energy, a collector, often fastened to a part of the roof facing the sun, heats water that is either pumped (an active system) or driven by natural convection (passive system) through it.

Solar hot water has many benefits:

• Investment that pays for itself in as little as 5 years
• Adds value to your property
• Saves your money on power bills 
• Saves greenhouse gas emissions

At the end of the day, why pay for hot water when you can get it for free?

And if you already have solar hot water, see the tips below to make sure your using yours efficiently:

• Regularly clean panels so they are not dirty
• Ensure they are not shaded at any time of the year
• Check that the booster is switched off at the power board, unless there is a long period of no sunlight (e.g. in the wet season)

COOLmob tip: when installing the solar hot water unit on your roof position it so as to allow installation of solar PV panels at a later date.

Electric Hot Water Systems

Electric hot water systems use electricity from the grid to heat the water you use for cooking, cleaning and showering. Electric hot water systems can be very expensive as they require a large amount of energy to maintain water temperatures. However there are still some things you can do to ensure that it is running efficiently.

• Check to see if your hot water tank is loosing a lot of heat by feeling the sides of it. If it is hot (above room temperature) then it could do with some extra insulation. Insulation can be as simple as wrapping the tank in a blanket to keep heat in
• Try turning the thermostat down to 60°C (it is usually set at 70°C) as this should be enough hot water needed for showering. You can also save more on your hot water system if you use boiled water from the kettle for washing dishes.
• If going away for a period of time you can turn your hot water system off at the power board to ensure water isn’t heated unnecessarily when no one is home. Do this if you are going away for a week or more.
• If you have mixer taps (i.e. one tap for both hot and cold flows) ensure that it is always in the ‘cold’ position and not in the middle. Only put it towards the ‘hot’ position when hot water is needed (and you aren’t able to use boiled water from the kettle)
• Wash your clothes in cold water wash cycles instead of hot water, and only wash when you have a full load.

COOLmob often audit homes that are over-lit and have energy intensive lighting types. For some families lighting makes up a significant amount of quarterly energy bills. The good news though is that switching to energy efficient lighting is one of the easiest ways to reduce your energy bills. If you have halogen or compact fluorescent lights in your home, switching over to LEDs is a simple way to reduce your energy costs. 

LED lighting

Light emitting diodes, known as LEDs are very energy-efficient light bulbs. Because they’re able to convert 60% of electricity into light, compared to only 5-10% for compact fluorescents, these lights use much less energy. Compared to halogen bulbs, LEDs use 75% less energy and last 5 to 10 times longer. Have a look at this graph from Energy Rating comparing the lifetime cost of LEDs, CFLs and halogens (Australian Energy Foundation, 2020).

If your existing fitting is a GU10 (and not a pin fitting as in the second image) then you do not need an electrician to remove the transformer and replace the lamp holder and fitting. You can simply put the CFL globe straight in and start cutting your power bills immediately! If you are unsure, take one globe out and take it to a lighting shop to ask what the correct fitting is. The lighting shop will be able to tell you what type of replacement globes to buy.

There are also lots of alternatives online so make sure you shop around for the best result.

Down Lighting

There are an array of lighting types on the market. A common down light is the tungsten halogen, which is also a very energy intensive light and therefore expensive to run. Remember: A low voltage lamp does not mean it uses less power. If you want to use less power you need a lamp with a lower wattage light. 

Easy savings from lighting

• Turn the lights OFF every time you leave the room. It is a common myth that it takes more energy to turn on a light than you save by turning it off when not needed
• Don’t over-light areas
• If you have more than one light on a switch (as is common when using halogen down lighting), consider removing some of the globes to reduce the amount of power used per switch
• Optimise natural lighting where possible. Make sure rooms are well lit with the curtains open to let the light in

Longer term savings

• Install movement sensors to outside lighting
• Install a skylight to high use areas such as the kitchen, living room, bathroom or laundry
• Re-wire lights that are on the same switch so only the lights that are needed come on (for example separate the lights in the kitchen so only sections come on at once)
• Have an electrician remove the transformer and replace pin fittings and lamp holders with GU10 fittings that are compatible with more energy efficient lighting types

Many of the COOLmob households audited in Darwin have a swimming pool. At the time of these audits the majority of pools were set to operate their pumps for 8 hours a day. This equates to electricity costs between $3,500 and $5,500 over a 5 year period, and creates between 12 and 19 tonnes of greenhouse gas emissions over the same period. The good news is that there are plenty of opportunities and ways to cut costs on your pool pumping. There are savings opportunities for both ‘salt’ and ‘chlorine’ pools, though each may require different changes.

Money saving tips

Reduce pump operating times

The first and easiest solution to the high electricity costs involved in pool pumping is to reduce the operating times of your pump. Reductions of 2 hours for ‘salt’ pools and 3-4 hours for ‘chlorine’ pools can be achieved, however these changes can vary between pools because of:

• pump size and characteristics
• filter type
• water quality management
• pool environment and usage.

Savings of about $900 and $1,600 over 5 years are achievable for a 1kW motor for the ‘salt’ and ‘chlorine’ pools respectively. This equates to greenhouse gas emission reductions of 3 and 5 tonnes in the same period.

When reducing times make sure the water quality is checked periodically.

Use a pool cover

The next savings option to use a pool cover. A pool cover will not only prevent water evaporation, but it will protect the pool when it is not in use, meaning you won’t need to pump as much!

The fitting of a pool cover for approximately 3 months of the year will achieve significant savings of nearly $700 over 5 years, and reduce your greenhouse gas emissions by a further 2 tonnes of CO2 (based on the operation of a 1kW pump motor).

In addition to the electricity savings in reduced pumping costs as a result of a pool cover, one COOLmob household found that they didn’t require the 9,000 litres of ‘top up’ water while the pool was covered during the dry season.

Use an energy efficient pool pump system

There are energy efficient pool pumps and controllers now on the market. These have been developed to use automated variable speed drive technology to achieve significant power savings on pumping. There are two main forms:

• a variable speed pump motor that replaces any existing pool pump and is available in 2 sizes for large or standard pools; or
• a controller that is installed by a simple plug-in action into an existing pool pump

Both items achieve savings of 65-70% operating power costs and greenhouse gas emissions compared to standard pool pumps, and are much quieter to run. Claims are also made regarding increased effectiveness of filtering and longer pump life because of the lower operating speeds. Pumps may need to be run for a little longer than your present pump settings in order to turn over the same amount of water, due to the slightly slower flow rates. The savings have been verified by COOLmob and the reduction in noise level is an added bonus.

The automatic speed controller can be fitted to any size pool pump.