In Australia, there are many different brands of solar hot water heaters, and lots of different options for each brand. Here's a list of brands and explanations for each (including links to the manufacturer's sites).
Some brands only do roof-mounted thermosyphon systems, some only do split system (ground tank) systems, but all of them have options for different tank sizes, types of boosters (electric or gas) and some brands do everything including heat pumps, retrofits and preheaters.
Here's a list of brands available in Australia.
Whichever brand you choose, it's best to get advice from a Solar professional on the size and strength of system you'll need for your home.
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