Where is my home's energy going?

Before you can improve your home’s comfort or reduce energy costs you need to know where the energy is going.

The problem is that every home is different, and energy flows depend on location, house design and other factors. So, if you live in South Australia, say on the Adelaide plains, then the answer is different from if you live in Melbourne or Sydney. It will even be different if you live in in the Adelaide Hills.
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This is why it is important to think critically about where the advice you are looking at is coming from.

Poor Sources of Advice

One of the worst sources of advice is from home improvement shows. They can be fun to watch, but take everything with a grain of salt. Often the products spoken about are from sponsors and might claim product ‘A’ can save you up to say 76% of energy loss, without saying what location, what type of house and what type of heating and cooling they are using.
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Also be aware of you tube videos, it can be difficult to find the source of the video and often the information is wrong for your location (particularly if from overseas). This particularly applies to advice on how to keep cool from the colder parts of America or Europe. What works if the maximum temperature is 26 degrees is not going to work if the temperature is 40 degrees or hotter.

Where is my house losing heat?

If you are trying to improve comfort, the chart below shows the minimum, average and maximum percentages that the different cause of heat loss can have for a range of existing homes in and around Adelaide.

Note that these figures differ from the Your Home data as they are for the Adelaide area, and not for Australia as a whole.
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This shows for example that if your windows are only 15% of heat losses but your floor is 30% of heat losses, you should concentrate on the floor first, although for most people the windows are a better place to start.

What is costing me money for energy?

Similarly, if your goal is to reduce energy costs, then the following chart shows the range of energy use cost estimates from recent Residential Efficiency Scorecard assessments before improvements (again in the Adelaide area).

This shows that in most homes heating and cooling dominate. Heating energy cost is usually more than cooling energy cost. However, hot water can be expensive, depending on your usage and type of water heater.

Lighting is usually minimal unless you have lots of halogen down lights.

I have ignored pools and spas to avoid distorting the results, but if you have one it could easily be 35% of your energy costs.
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Note that Scorecard ignores cooking and other appliances, because in general their energy use is low. Newer appliances tend to have much lower energy consumption than old appliances, due to minimum performance ratings and/or star ratings helping you choose efficient appliances. An admittedly extreme example is when our 20-year-old TV died, the same size replacement TV only uses 10% of the electricity that the old one did.

Recommendations

Even though this data is from one location, there is still a huge variability. If you intend investing a significant amount of time or money over the next few years, you want the best bang for the buck, so you don’t waste money and time on something with no noticeable effect. To do this:
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• Check that your sources of information are relevant.
  • ​Use information from your region.
  • Check that the information is relevant for your house type.
  • Beware of sponsored content.
  • Consider getting a home energy efficiency assessment. It will save you much more than the cost, and ensure you achieve your goals quicker.