All about energy

Energy basics

Energy comes in many different forms, however, the ones we will be referring to in relation to our homes and lifestyle are electricity and gas.

The base unit for measuring energy is the Joule. 1,000 Joules is a kilojoule, a term we are familiar with in relation to our diets. When we talk about food we are referring to the amount of energy contained in a portion of a particular food. Natural gas is billed in megajoules (MJ) which is simply 1,000 KJ. We are billed for electricity in kilowatt-hours (kWh).

To compare the energy used in a gas appliance to the energy used for an electrical appliance, you can use the simple formula 3.6 MJ = 1kWh.

Generation issues


Victoria currently holds the ignominious title for producing electricity with the highest volume of greenhouse gas emissions in Australia. This is due to the fact that most of our electricity comes from burning brown coal. Brown coal contains a large amount of water that has to be ‘cooked’ out of it (using a lot of energy) before the energy in the coal can be accessed.

There has been discussion in the media in recent years about ‘clean coal’ as an alternative to reduce emissions. The industry states that by a process of removing water content from brown coal, it makes it ‘cleaner’. However, this process only brings it up to being equivalent to black coal, which is still an emissions-intensive fuel, as well as being a finite resource.


Gas is much cleaner fuel than coal, contributing a fraction of the amount of greenhouse gas emissions for the equivalent amount of energy. However, it does still produce some emissions and it is a finite resource that will only last a short time under current rates of population and industrial growth. It is becoming known as a transition fuel, something we can replace coal with now to immediately reduce emissions until we can support all our energy needs with renewable energy.

Unconventional gas includes gas extracted from rock through a process called ‘fracking’. This type of gas lies in small cavities inside porous rock. Fracking is an explosion created to release the gas for collection and use. Once the gas is released, water is pumped back into the rock to stabilise the pressure. Unfortunately, this process may have potential side-effects on the environment such as groundwater contamination, methane emissions into the air and high levels of water consumption.

Reading your energy bills

Unfortunately, there is no such thing as a standardised energy bill. Each retailer has a different way in which they set out their bills, and some are easier to understand than others. Your retailer is obliged to help you understand what the different parts of your bill mean, so if you can’t make head or tail of it, ask them.

There are several essential things you need to be able to ascertain from your energy bill:

  • How much energy have you used?
  • In what time frame have you used it?
  • What are you being charged per unit of energy (e.g. per kWh for electricity, MJ for gas)?
  • Are you charged at different rates for different times; do you have an off-peak rate?
  • What are the service charges you are paying?
  • Is the reading an ‘actual’ meter read, or ‘estimated’?

This is an example of the layout of a typical energy bill (0.12MB).(PDF, 127KB) 

Once you know how much total energy you are using, you can compare it with what other homes like yours are using, and work out what goals you might implement to reduce energy use. The average electricity use per person can be found in this Nillumbik map (0.1MB)(PDF, 104KB).

Measuring energy

One of the best ways to reduce the energy you use is through simply understanding how, when and where you use it. Once you know this, it is so much easier to work out which actions will be the simplest and most effective at reducing your energy use – and your energy bills. There are a variety of tools that can help us with this.

Power meter

This tool can show you how much energy a particular appliance uses. The meter is plugged into the power point, then the appliance is plugged into the meter. Once the appliance is turned on, the meter will tell you how much power is being used. These devices are great for once-off readings to get to know your appliances. Cost: $30 upwards from hardware stores
Note: if you want to read energy usage for a machine that cycles on and off (such as a fridge), you need to let the device measure for a period of time, such as 24 hrs, and then work out the average hourly use.

Don’t have a power meter? No problem, you can borrow a Sustainable Home Audit Kit through the Yarra Plenty Regional Library. These kits contain an audit checklist, power meter, water flow cup, thermometer and instructions on how they can be used.

In Home Device (IHD)

This tool consists of two parts. The first unit connects to your meter box and measures energy use. The second is an LED display that can be positioned in a convenient location in your home, such as your kitchen counter. The LED display takes the readings measured at your meter box and displays that information to you in real-time.

The IHD can include a software package that allows you to download usage data onto your computer so that you can compare your usage across days, weeks and months. These devices are great educational and motivational tools because you can see the amount of energy being used at any one moment. The cost of an IHD varies and may require an electrician to connect it to your meter box.

Web portals and Apps

Many of the major electricity retailers offer their customers the opportunity to log in to their own personal web portal or app where the customer can see graphs and statistics about their energy use over time. SP Ausnet also offers an energy portal. While not a retailer, they are the supplier for the Nillumbik region so this is a great option if your retailer doesn’t offer a portal.

These web portals and apps gather their data from smart meters, so they are only an option if you have a smart meter installed at your home, and the smart meter is being read remotely (this is not the case for all of Nillumbik, and may delay your ability to access this data). At present the following web portals or apps are available:

Supplier energy portals
 SP AusNet  

My Home Energy


United Energy


Energy Easy




Electricity Outlook


Note: SP Ausnet is the supplier for all homes in the Shire of Nillumbik. If your home is elsewhere in Melbourne, United Energy or Jemena may be your supplier.

Retailer energy portals

AGL Energy App


Energy Australia


My Account




Powershop Mobile Apps


Origin Energy


Origin App

Web portals are a good way of understanding your own energy use because you can see the changes over time. They also help you keep longer-term track of any changes in your energy use, as well helping you spot fluctuations, which might indicate a problem, such as a faulty hot water heater.

Interval reports

Another opportunity to get a better understanding of your energy use over time is to contact your retailer and request an interval report for several months energy use. This report will often be sent as an excel file, showing energy use in half-hour intervals. You can use the data in the interval report to calculate average energy use at different times of day, compare day totals with each other, and many other things. Please note that usually you will need to have a functioning smart meter for your retailer to be able to provide you with an interval report.

Electricity pricing

Existing meter pricing structures
Single rate

This is where you pay a single rate for all power used in your home, with no variation for on or off-peak.

Controlled load

Controlled load pricing is common in homes with high energy use electrical appliances, such as electric hot water heaters and in-floor heating. These devices have been hard-wired into a different circuit in your meter box that classifies as off-peak so that water and floor heating will operate between 11pm and 7am. The benefit of this for the householder is that energy used by these high energy use devices will be charged at the lower off-peak rate.

If your home is on this pricing structure you will see two usage readings on your power bill – one for ‘peak’ and one for either ‘off-peak’ or ‘controlled load’.

Time of use

This structure gives the highest flexibility to the householder to take advantage of lower pricing brackets by adjusting their use of power to different times of day. For example, rather than set the washing machine going at 5.30pm, and pay the associated peak price, you set it to turn on at 2am, and pay the associated off-peak rate.

If your home is on a ‘time of use’ pricing structure, your retailer will be charging you their peak or highest rate for each unit of energy used between 7am and 11pm weekdays. For energy used between 11pm and 7am weekdays and all weekend, you will be charged at the lower off-peak rate.

New pricing structures

Flexible pricing (used to be called ‘time of use’)

Once a smart meter is installed at your home and is communicating with your energy retailer, you will have the opportunity to choose from a variety of pricing arrangements. Flexible pricing structures are made possible because your Smart Meter records the energy you use in 15 minute increments, allowing billing at different price rates for different times of day.

Two things to remember are:

  1. You will not automatically be moved to flexible pricing when you get a smart meter, you need to request it (and it is optional – you don’t have to)
  2. If you switch to flexible pricing, you can back at any time. However, depending on the contract you have accepted, you may have to pay some additional fees or charges. Discuss any potential costs associated with moving back to your previous plan or another plan with your retailer before accepting a new plan.
What flexible pricing looks like

Flexible pricing involves three different rates. Here is an example of how you may be charged:

  • Peak – from 3pm to 9pm weekdays will be charged at a high rate.
  • Shoulder – from 7am to 3pm and 9pm to 10pm weekdays and 7am to 10pm weekends will be charged at a rate that is lower than the Peak rate but higher than the Off-peak rate.
  • Off-peak – from 10pm to 7am every day will be charged at a low rate.

Before making any decision to change to flexible pricing, it is really important to get to know your pattern of energy use by monitoring your web-portal or IHD for a couple of months or request an Interval Report from your retailer covering about three months of data.

By working out how much power you are using over different time periods, you will be able to see how the application of different pricing at different times of day would affect your bill.  You also need to know exactly what flexible pricing plans your electricity retailer offers as they may vary slightly between retailers.

Once you have a good understanding of your energy use pattern, you may decide that you could run certain appliances at different times of day to capitalise on off-peak rates, or you may realise that there is no point switching your pricing schedule.

Remember - flexible pricing may decrease your bills, but if you move without knowing your household energy patterns, it could increase them, so exercise caution. 

Diagrams and further information on flexible pricing rates can be found on the Victorian Energy Saver website or call 136 186.

Using solar electricity (solar PV) to your advantage

If you have a solar electricity system, keep in mind that most of the electricity it generates will be generated between around 10am and 4pm, the peak solar period when sunlight is strongest.

If your solar PV system receives the highest feed-in tariff (around 66 cents per kWh), you are best off sending as much of the electricity you generate as you possibly can, straight into the grid so that you can be paid 66 c/kWh for it. Try to use your appliances before 10am or after 4pm, when you will only pay the average retail rate of 28 c/kWh you use, rather than using your own solar electricity which is worth a lot more if you export it to the grid.

If your solar electricity system is quite new, or has not yet been installed, you won’t be eligible for the high feed-in tariff. If your feed-in tariff is currently about 10 c/kWh, it will be in your best interests to do the opposite of what we describe above. You need to aim to use as much of the electricity your system generates as you possibly can, between the hours of 10am and 4pm when it is being generated. This is because it is free electricity for you and saves you having to purchase it at any other time of day at the average retail rate of 28 c/kWh. 

How can you reduce your electricity bill?

1.    Know how much power you use and when you use it

Until you know how you are using energy, you won’t know where best to save it. Use an In-Home Monitor, a web portal, or an interval report (all explained above) to help you know where, how and when you are using energy in your home.

2.    Get an understanding of what appliances are using energy

Your home may be slightly different but the average Victorian household spends their energy dollars on the following: 

  • Heating: 32 per cent
  • Whitegoods: 17 per cent
  • Hot water: 16 per cent
  • Lighting: 11 per cent
  • Entertainment : 10 per cent
  • Appliances: 8 per cent
  • Cooking: 4 per cent
  • Cooling: 2 per cent

Source: Sustainability Victoria, At home - Sustainability Victoria

Audit the energy use of all your appliances with a power meter (see above) to see how energy use in your home stacks up. You can borrow a Sustainable Home Audit Kit through both Eltham and Diamond Valley Libraries (Yarra Plenty Regional Libraries).
3.    Set some energy reduction goals

For a simple way to establish an energy reduction goal, visit Sustainability Victoria's Save Energy website. This site focuses on small changes which can result in large savings, from changing to more energy-efficient light bulbs, to focusing on energy effient appliances when updating.

4.    Reduce your need for energy, particularly for heating

As they say, the cheapest energy is the energy you don’t use! By improving the way your home is able to maintain its temperature, you will be able to wait longer before resorting to energy-driven appliances to help you heat and cool it.

Installing or improving draught proofing, insulation, shading, window coverings and ventilation are all ways you can reduce your use of appliances to stay comfortable. Another great way to lower costs is to simply reduce the amount of space you are trying to heat or cool by sealing off living areas from other less used rooms and wet areas such as bathroom and laundry.

Not only can you reduce your need for energy to heat and cool, but when you do turn on your heating or cooling appliances, the warm or cool air will be held in your home for longer without having to be replenished.

There are loads of tips for improving your building shell in the Practically Green At Home Guide, a free publication developed by Council that is available at Libraries in Nillumbik and from the Council Offices.

5.    Reduce the amount of energy your appliances use

One simple way to do this is whenever you are replacing an appliance, purchase the most energy-efficient model you can. The government Energy Rating website can help you compare brands by star rating and energy use.

To read more about choosing energy efficient appliances, grab a free copy of Council's Practically Green At Home Guide.

Some other simple ways to reduce the energy use of most appliances are to:

  • keep them well maintained (check heater and cooler ducts for cracks and leaks, clean filters regularly, check pilot lights)
  • heat and cool to optimal temperatures and not more (between 18 and 21 degrees in winter, between 25 and 27 degrees in summer)
  • make sure your hot water heater is not over-heating and that pipes are well insulated
  • switch appliances off at the wall to reduce standby power use
  • position them well. For example, fridges and freezers need to be in a cool, well-ventilated space to work most efficiently, and heaters should be positioned away from windows.
6.    Consider switching to a flexible pricing structure

If after doing your homework (described in more detail above) you decide to switch to a flexible pricing structure, programme as many of your appliances as you can to run during off-peak periods when you pay for electricity at a lower rate.

7.    Use existing solar PV to your advantage

If you have solar electricity (solar PV) with a 10 cent per kWh feed-in tariff, programme as many appliances as you can to use your free solar energy during peak solar hours, typically between 10am and 4pm.

Need more help reducing your energy use?

Here are some great resources that can help you reduce energy use in your home.

Check the other Sustainable Living pages from Council's website:

  • Beat the summer heat
  • Winter warmers
  • Green living for renters
  • Green living for landlords
  • Green living for homeowners

Sustainability Victoria - You can find tips on reducing energy use in the different areas shown on the graphic by clicking on that heading. This site has information on recycling, purchasing more energy efficient equipment, rebates and much more for Victorian householders

Victorian Energy Saver - This Victorian Government website is all about energy, and how you can take charge of your own energy bill. Lots of great tools and information, including how to work out if flexible pricing might work for you

Build It Back Green - Developed by the Alternative Technology Association in conjunction with Green Cross Australia, this website is an easy-to-use resource with a special focus on improving the energy efficiency of your building shell and the equipment you purchase and use

Renew - Formerly known as the Alternative Technology Association, Renew is a not for profit member organisation whose aim is to assist people to make sustainable choices in their homes and communities. They have excellent community forums where you can ask questions related to sustainability and energy efficiency or research the many previous discussions for answers

Smart (Green) Renters Guide  - Either download a copy or check out their web pages for sustainable living tips for renters

Green Renters - A Victorian not-for-profit organisation that provides sustainability advice to people living in rental accommodation