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Your daily ray of solar hot water


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.