Solar Hot Water Systems, to be effective, need to be sized accordingly.
Size of solar tanks and the number of collectors or tubes comes down to the daily needs of the household.
As a rule of thumb Australians use an average of 50-70 litres of hot water per day, so for a normal family of 3-4 people the tank should be sized between 250 and 330 litres. This means that households generally have at least 1.5 days of hot water in the storage tank to account for cloudy and overcast days,
With flat plate collectors it is recommended to have at least 1 square metre per occupant. Most manufactures panels are two metres squared so for a normal 3-4 person household 2 panels are required. When using evacuated tubes a typical 10 tube system has a surface area of 1.8 square metres. So for a 3-4 person household 20-30 tubes should be used.
Size of solar tanks and the number of collectors or tubes comes down to the daily needs of the household.
As a rule of thumb Australians use an average of 50-70 litres of hot water per day, so for a normal family of 3-4 people the tank should be sized between 250 and 330 litres. This means that households generally have at least 1.5 days of hot water in the storage tank to account for cloudy and overcast days,
With flat plate collectors it is recommended to have at least 1 square metre per occupant. Most manufactures panels are two metres squared so for a normal 3-4 person household 2 panels are required. When using evacuated tubes a typical 10 tube system has a surface area of 1.8 square metres. So for a 3-4 person household 20-30 tubes should be used.
Hot water systems should be located closest to the wet areas in the house - particularly the kitchen, as although the majority of hot water is used in the bathrooms, the kitchen is more frequently used through the day meaning the wait time is multiplied more times in the kitchen. This can ultimately influence the type of hot water system chosen as the hot water on an electric boosted tank is delivered straight from the tank - so when mounted on the roof, hot water can be delivered quicker to a lot more areas in the house from a middle roof position.