These systems have solar collector panels and a storage tank. For a 4 person home, you will generally need two solar panels, or four square metres, along with a 300-360 litres tank.
The larger tank is needed to make up for days of minimal sunlight. Also note that four square metres of panel is recommended for an ideal collection position.
If your home doesn’t allow for your panels to be set up in an ideal place where they get a lot of direct sunlight, you may need to invest in more panels.
Some solar hot water systems also have an electric or gas booster element in the storage tank as a backup, to keep you going through periods without much sunshine.
Unlike electric hot water systems, solar hot water systems are typically the most expensive to buy as well as install.
But also unlike electrical hot water heaters, a well-functioning solar hot water heater will be very inexpensive in the long run as the running costs can be extremely low.
You may also be able to take advantage of government rebates or other incentives to help out with the purchase cost.
Solar systems, not including installation, will generally cost around $2000-$7000.