Using solar energy to heat water is an effective way to use Australia’s abundant sunshine, save energy, save money and reduce greenhouse gas emissions. Solar Water Heaters (SWHs) make up around 13 per cent of all hot water systems used in Australia.
Installation is important and depending on your location, direction of solar panels and the amount of water you use, a SWH could provide 50 to 90 per cent of your hot water needs.
The Solar Water Heater Product Profile released in 2014 has more information about the market and operation of SWHs in Australia and New Zealand.
What is a solar water heater?
A solar water heater uses energy from the sun to heat water for your home. Solar panels on your roof collect energy from the sun’s rays to heat water which flows to a storage tank, ready for use.
There are many different types and configurations of solar water heaters available. It is important to select the type that is most suitable to your family size, climate, house type, roof characteristics, water quality, available space and aesthetic preferences.
How does it work?
- Cold water flows from the tank to the solar collector, usually positioned on your roof. In a split system like the one shown below, cold water is pumped up to the collector. In a thermosiphon system where the tank is mounted on the roof above the collectors, cold water flows naturally into the collector because it is heavier than hot water.
- The solar collector is made of materials that absorb heat from the sun very efficiently. The cold water travels through the collector and the heat in the collector heats up the water, which returns to the tank
- Hot water rises to the top of the tank and colder water is taken from the bottom and returned to the solar collector. When you use hot water, it is taken from the top of the tank where the water is hottest.
The two most common types of SWHs are close-coupled thermosiphon systems and split systems. Consumers can choose between many component types to suit the needs of the home. Generally you can select:
- Boosting options
- Gas (natural or LPG)
- Flat plate panels
- Evacuated tube collectors
- System configuration
- Split systems
- Electronic controls
Solar split system
Regulation for Solar Water Heaters
Solar Water Heaters (SWHs) and their components are not covered by regulations that require them to meet any minimum prescribed levels of energy efficiency or performance.
The exception is gas boosted SWHs where the gas storage tank is subject to MEPS requirements.
Electric boosted SWHs are currently provided an exemption to the tank heat loss requirements that other electric storage tanks must meet.
These issues are now under investigation.
At a glance...
|MEPS||Energy Rating Label||Australia||New Zealand|
|Solar Water Heaters||No||No||-||-|
What are we working on?
Zoned Energy Rating Label
The energy efficiency and performance of certain appliances can be impacted by where it is installed (location) and other factors such as usage patterns and climate variations, including air temperature, water temperature, frosting, humidity and cloud cover.
A Research Report setting out the methodology and technical elements for a Solar Hot Water ZERL was released in December 2015. Consultation on the report was undertaken between December 2015 and 1 February 2016, and focused on the feasibility and robustness of the technical elements of the proposed approach. Consultations are now closed on this report.