Heating options for an energy efficient home
We have been discussing all the different ways you can ensure you have an energy efficient home. Here we discuss how you can keep your family warm and cosy throughout the colder months.
In most Australian households heating accounts for around 60% of your power bill. That is split to 40% for heating and cooling air and 20% for heating water. We have already shown how much electricity it takes to keep your home cool in summer. Of course using a reverse cycle air conditioner, it will cost about the same to keep your home cosy in winter.
Here we compare the four different systems predominately used to provide hot water to your home.
On average in New South Wales, there are more than 250 days of sunshine every year. Capturing the warmth from that sunshine to heat your water, will ensure you have an energy efficient home. As a result, it will also significantly reduce your electricity costs.
Installing a solar hot water system is the most efficient way to capture the heat of the sun to supply hot water to your home. There are two common systems currently available in Australia.
- Flat Panel
This system uses copper pipes which run through a glass covered panel and are connected to a water storage tank. These panels and tank are usually mounted on the roof, facing north to capture the maximum amount of the suns’ rays.
- Evacuated Tube
A more efficient system as it doesn’t necessarily require direct sunlight to work. Because of the vacuum created inside glass tubes, this system works well, even without direct sunlight.
Whilst we enjoy a relatively sunny climate, there can be days and sometimes weeks when the sun does not appear. To ensure your energy efficient home does not run out of hot water, the solar system can be supported by either an electric or gas booster system if required.
The department of Environment and Climate Change in New South Wales estimates that by installing a solar water system you are likely to reduce your water heating costs by a whopping 75%.
Whilst the initial cost of a solar hot water system can be significant, the cost savings to your family budget will often negate this. There may also be federal government rebates available to assist with this upfront outlay.
Gas Hot Water System
As the name suggests, a gas hot water system uses either natural gas or LPG. Natural gas is usually connected via a piped network, whereas LPG is often supplied in bottles and delivered to your home.
There are two main types of hot water systems:
- Storage system will heat water in an insulated tank and be available for use at any time. This system is better for larger households.
- Instantaneous system will only heat the water when it is required. As a result there is no loss of heat from a storage tank. This is a more energy efficient system than a storage system and works well for smaller families.
Generally a gas hot water system will have a lower upfront cost than a solar system. However you must also take into account whether mains gas is available of if you will need to purchase bottled gas, which can become expensive. When purchasing a hot water system of this kind, you should look at one with a 5-star rating. This will save you around 15% on running costs.
Basically, a heat pump hot water system uses the same principle as a refrigerator. But instead of extracting heat out of the fridge to keep it cool, it pumps heat into water to warm it. As a consequence, this system is sometimes referred to as “air-source” heat pumps.
If the outside temperature is greater than the cold refrigerant, then the heat pump will absorb heat and move it to the water. Obviously, if the outside air is warmer then it will be easier for the heat pump to warm the water. Consequently if the ambient air is lower, less heat can be transferred. Therefore, for a more energy efficient home a heat pump hot water system will work better in warmer climates.
Whilst they are powered by electricity, the heat pump system is approximately three times more efficient than a conventional electric hot water system.
Electric Hot Water System
As with gas hot water systems, electric heaters are available in both storage and instantaneous systems.
Most storage systems use an insulated tank to store water at a temperature between 60-80 degrees. Typically using an element similar to an electric jug, but an electric hot water system will maintain the water at that temperature.
However over time, this temperature will decrease through the walls of the storage tank and of course when hot water is used. At this time, the tank will be refilled with cold water. Then of course electricity is used to bring it back to the required heat.
Whilst not as common as a storage system, an instantaneous system heats when you turn on the tap. Hot water is heated instantly by electricity and delivered to the bath, shower or sink. An instantaneous system obviously requires significantly more power than other systems and is not a good option for an energy efficient home.
Other ways to keep your family warm this winter
- With between 80-90% heat lost through your ceiling, insulating your roof will have a significant impact on keeping your house warm.
- Make sure your windows have close-fitting curtains to help contain heat inside your home and prevent heat loss by 40%.
- By keeping your internal doors shut you will conserve heat in the room. Also make sure the seals are tight on all windows and doors to prevent draughts.
- Let’s not forget the warmth and cosiness that a beautiful throw rug can provide. Often used as a decorator item, a soft wool rug will really keep you snug through those cold winter nights.